dermatology1.1 Flashcards

Question

Eccrine sweat glands

Answer 1

Traditional sweat glands distributed over most of the body. Not found in the lips, under the nails or on the glans penis, glans clitoris, or labia minora. Watery, enzyme-rich secretion, initially isotonic, becomes hypotonic as Na+ is reabsorbed by the ducts. Important for thermoregulation

Answer 2

Develop in utero with down growth of the epidermis forming a pilosebaceous unit. The hair itself consists of a central medulla of soft keratin, and a cortex and cuticle of hard keratin. Hair growth is intermittent; a growth period of 2 to 3 years is followed by a rest period of several months. Pigment comes from melanocytes at the base of the hair. With contraction of the arrector pili muscle (smooth muscle), hairs stand on end (“goose bumps”)

Answer 3

Oil glands which secrete sebum, a complex mixture of lipids. develop along with hair follicles and empty their secretion into the upper one-third of hair follicles. development accelerated at puberty

Answer 4

a tough but elastic support structure that lies beneath the epidermis and above the subcutaneous tissue. The dermis contains blood vessels, nerves, and cutaneous appendages (hairs, sweat glands/ducts, etc.) that are important to the structure and function of the skin as an organ. The dermis ranges in thickness from about 1-4 mm, depending upon the body location. Clearly, this is much thicker than the epidermis, which is on average, only as thick as this piece of paper. The epidermis contains no blood vessels, it depends upon the dermis for all its nutritional support. The dermis also provides the strength, resiliency and plasticity of the skin. The dermis may be further subdivided into two zones: a) the papillary dermis (located immediately beneath the epidermis), and b) the reticular dermis located deeper in the tissue. Dermal matrix is a term often used to describe the admixture of collagen fibers, elastic fibers and ground substance all of which are synthesized by dermal fibroblasts.

Answer 5

also known as adnexal structures, is a term used by dermatopathologists to refer to the hair follicles, sebaceous glands (oil glands), and sweat glands found in the skin that are vital to protection and homeostasis.

Answer 6

The epidermis may be located on top and functions chiefly in protection. The dermis is located immediately beneath but above the fat. There are interlocking dermoepidermal junction.

Answer 7

The downward projections of epidermis, interdigitate with upward projections of the dermal papillae. This interlocking pattern affords both strength of adherence, and also increases the surface area between the epidermis and dermis, which is important as the dermis is the sole source of nutrients for the epidermis. On the hands and feet, this interlocking pattern becomes so pronounced that it contributed to the epidermal ridges, known better as “fingerprints.” The dermal papillae makes up the papillary dermis, while the deeper layer of the dermis is referred to as the reticular dermis.

Answer 8

The dermis is composed predominantly of collagen fibers, elastic fibers and ground substance. All these materials are synthesized by a highly productive, but sparsely populated, spindle-shaped cells in the dermis known as fibroblasts.

Answer 9

Collagen is one of the basic building-blocks of the dermis. It provides essentially all the tensile strength of the skin. The body synthesizes many different forms of collagen which are numbered with Roman numerals.

Answer 10

This form comprises >85 wt. % of the adult dermis. It is also a major component of bone.

Answer 11

This type of collagen comprises a large part of the fetal dermis but is not a major portion of the adult dermis. It is thought that this difference in expression explains why adult skin forms scars and fetal skin is much more resistant to scar formation.

Answer 12

This form is found in high concentration in the “basement membrane zone” which is present in the dermoepidermal junction. It is also more prominent around vessels and this explains the vascular fragility in some forms of Ehlers-Danlos syndrome.

Answer 13

This form is found in the anchoring fibrils which are used by the body to attach the epidermis to the dermis.

Answer 14

Procollagen is synthesized intracellularly within fibroblasts (likened to little tiny factories of the dermis). It consists of three separate chains of proteins arranged in an α-helical structure. Under the electron microscope this yields a characteristic pattern of striations with 68 nm intervals. The chains generally consist of repeated strings of glycine and two other proteins, forming a Gly-X-Y structure. The X and Y are usually proline and hydroxyproline. The synthesized collagen proteins are secreted and then are assembled into collagen fibrils extracelluraly. A number of cofactors are required to facilitate this extracellular assembly of collagen fibrils, the most famous of which is vitamin C (ascorbic acid).

Answer 15

Without vitamin C, the collagen fibers will not attain their final desired strength. As a result, minor wounds will fail to heal, hair will grow abnormally, and the blood vessels will be quite fragile due to inadequate support from the surrounding collagen. Teeth will fall out for much the same reason, a lack of surrounding collagen support. The condition used to be common in sailors who went without fresh fruits or vegetables on long ocean journeys, and was known as scurvy. Scurvy is a classic example of an acquired abnormality in collagen production. Scurvy is no longer a common occurrence, but other congenital abnormalities in collagen formation may lead to well-recognized disorders. For example, Ehlers-Danlos syndrome (EDS)

Answer 16

is a group of related disorders of collagen synthesis. There are at least ten subtypes of EDS; however, all of the subtypes share varying degrees of the 4 major clinical features including: skin hyperextensibility, joint hypermobility, tissue fragility and poor wound healing. It is tempting to want to believe that the hyperextensible skin in EDS is due to a disorder in elastic fibers, but this is not the case; the disorder is due to abnormally formed collagen. EDS is a classic example of disordered collagen production due to genetic defects.

Answer 17

Collagen fibers provide the skin with tensile strength, but elastic fibers provide the skin with resiliency. Roughly put, resiliency is the ability of the skin to be distorted but then return to its original shape. Elastic fibers are much smaller than collagen fibers. While collagen fibers form large eosinophilic (pink) bundles, easily recognized under the light microscope, elastic fibers are difficult to identify with standard staining techniques. Fortunately, elastic fibers are argyrophilic (silver-loving) and silver stains and other stains (such as the Verhoff-Van Gieson stain) may be performed to accentuate the presence of elastic fibers but will not stain collagen fibers. Just as there were acquired and hereditary disorders of collagen production, there exist analogous etiological disorders of elastic fibers. The most common acquired disorder of elastic is solar elastosis.

Answer 18

Over a lifetime, a person accumulates significant sunlight exposure, and this exposure leads to degeneration of the elastic fibers. These collagen bundles become dystrophic tend to “clump” and aggregate. These abnormal, sun-damaged elastic fibers become easy to appreciate on routine microscopy, as basophilic (blue) staining material within the superficial portions of the dermis. This solar elastosis is an important clue under the microscope as informs you instantaneously that the tissue is from a middle- aged or older person and was taken from a sun- exposed skin site. Such ancillary information will serve you well, as you study sun-induced neoplasms in the sections to come.

Answer 19

Inherited forms of elastic disorders exist, but they are rather rare. The classic example is pseudoxanthoma elasticum (PXE), which is caused by a mutation in a gene encoding for part of the “multidrug resistance complex”, an entity you will also discuss in your pharmacology course. The complex is responsible for pumping compounds out of cells, and when it is mutated in a cancerous cell it may result in resistance to certain forms of chemotherapy. It is not well-understood exactly how this MDR defect leads to disease, but the ramifications in the skin and other organs are well-recognized. In PXE, the elastic fibers of the dermis become enlarged, tangled, and calcified, resulting in a characteristic purple-blue color upon routine histological examination. Clinically, the skin of the flexural areas of the body maintains a “plucked chicken” appearance that serves as a clue to the diagnosis. Elastic fibers of the blood vessels are also damaged leading to hypertension and bleeding disorders, particularly in the eye.

Answer 20

Ground substance is a general term for a gelatinous material intercalated between and amongst the collagen bundles, elastic fibers, and appendageal structures of the dermis. It consists principally of two glycosaminoglycans: hyaluronic acid and dermatan sulphate. Glycosaminoglycans are complex molecules made up of proteins and sugars, and are capable of absorbing >10,000x their weight in water. It may be helpful to conceptualize this ground substance as "pie filling" made of long chains of sugar molecules. With the help of other compounds, called fibronectins ("glue") this gel-like mass functions like a sponge. Crudely put, under pressure it can expel bound water and then take it up again. This process helps to facilitate nourishment of the overlying epidermis by easily allowing a water-based environment for diffusion. In contrast to collagen fibers, which are renewed mostly when necessary (injury), the ground substance is constantly being destroyed, by enzymes like hyaluronidase, and then renewed via production from fibroblasts.

Answer 21

An excellent example of ground substance is the current cosmetic filler product called Restylane. This is simply pure hyaluronic acid produced via recombinant (yeast with plasmid) technology. Cosmetic dermatologists place this material under the skin to augment the tissue and remove lines and wrinkles. It is well-suited for this purpose for two reasons: a) it is a natural substance that is already present in the skin and it does not engender an immune response (unlike some bovine collagen fillers) and b) it absorbs a tremendous amount of water and amplifies the augmentation. Just like endogenously produced hyaluronic acid, Restylane is broken down by tissue hyaluronidases and it is not a permanent augmentation.

Answer 22

The epidermis contains no blood supply, and it derives its nourishment via diffusion of materials through the ground substance of the dermis. The easiest way to conceptualize the blood vessels of the dermis is to divide it into superficial and deep vascular plexi. The cutaneous vascular system is also considered to be important for a number of other functions as well including wound healing, control homeostasis, and modulation of inflammation/leukocyte trafficking.

Answer 23

the endothelium, a single-cell lining on the innermost surface of vessels, elaborates important cytokines including endothelial growth factor.

Answer 24

via a structure called the Sucquet-Hoyer canal, a smooth muscle derived valve-like structure, blood may be directed toward the skin during overheating, or away from the skin in hypothermia.

Answer 25

via the expression of intracellular adhesion molecules (ICAMs) white blood cells begin the process of first adherence and rolling, and second diapedesis, so that they may exit the vasculature to fight infection in the skin and soft tissue.

Answer 26

where actual capillary structures of the skin are contained, in the uppermost portion of the papillary dermis.

Answer 27

when the thickened scales of psoriasis are forcefully removed, pinpoint bleeding is noted at the area of removal. The sudden removal of epidermal scale leads to trauma in the capillaries of the uppermost papillary dermis, leading to the pin-point bleeding observed. The scale of psoriasis is entirely within the epidermis, and Auspitz sign does not violate the rule that there are no blood vessels in the epidermis.

Answer 28

warts. Verrucas are benign, virally induced neoplasms (growth) that require an increased blood supply simply to support the virally-proliferating cells. These proliferating vessels may be identified as brownish, thrombosed capillary structures in the center of the verruca. Indeed, the presence of central thombosed capillary loops is a reassuring sign that the lesion is in fact a wart.

Answer 29

A common disease involving the post-capillary venules. In this condition, some type of insult leads to the formation of immune complexes. The most common cause is Strep infection, but allergies to medicines, cryoglobulin production from hepatitis C, or a myriad of other conditions may precipitate it. Indeed in a great many cases, the cause is never identified (cryptogenic or idiopathic). This is due to the precipitation of immune complexes in the walls of vessels. Therefore, this represents an excellent example of a Type III – Gell & Coombs reaction pattern. The deposition of immune complexes leads to inflammation. Neutrophils attach to the vessel wall and degranulate yielding damage and the extravasation of red blood cells into the dermis. This process of fibrinoid deposition in the vessel walls, with infiltrating neutrophils and neutrophil debris is called leukocytoclasia. Clinically, the vasculitis manifests as “palpable purpura”. It is palpable because of the inflammation, and it is purpuric due to the extravasation of RBCs. Such erythema is non- blanchable, because the RBCs have been extravasated into the dermis. Pressure applied to the skin with a finger does not make the redness go away as it would if the vessels were dilated but intact.

Answer 30

the epidermis is completely dependent upon the dermis for nutrition and support, any process which corrupts the dermal vascular plexi, whether a vasculitis (inflammation), vasculopathy (mechanical occlusion) or otherwise, if prolonged and/or severe, may lead to necrosis and sloughing of the epidermis.

Answer 31

function in a similar function as does nervous tissue in other areas of the body, specifically to inform and protect. Free nerve endings pass through the upper dermis to terminate at the dermoepidermal junction and these structures are thought to be involved in the sensation both of pain and also of itch, which in dermatology is called pruritus. Pruritus originates in free nerve endings near the dermoepidermal junction and is conducted centripetally by afferent nerves entering the spinal cord via the dorsal roots. These afferent nerves for pruritus are small, unmyelinated C fibers with a slow conduction rate. After entering into the spinal cord, the primary neurons synapse with secondary neurons whose axons cross to the opposite side of the body and then travel cephalad. Finally, these sensations arrive at the cerebral cortex. Here the body is capable of identifying the location, nature, intensity and other qualities of the itch sensation. Investigation by positron emission tomography demonstrated the secondary activation of the pre-motor areas of the brain and probably there exist synaptic connections to the motor area of the cortex, which prepare for scratching.

Answer 32

For a long time it was thought that itch represents a weak pain, and there was a debate whether the same nerves conduct itch and pain. Now it has been recognized that itch and pain are different and independent sensory modalities, even if local anesthesia or cutting of the sensitive nerves may abolish both. The following observations have led investigators to believe that receptors and transmission apparatus for itch and pain differ: itch elicits scratching, while pain yields a withdrawal response, morphine relieves pain but can actually produce pruritus, heating of the skin to 41°C relieves itch but not pain, and removal of the epidermis and upper dermis abolishes pruritus, but not pain. are structures which resemble an onion in cross-section. They are involved in pressure and vibratory sensation. It is not surprising, therefore, that they are most concentrated in the genital area.

Answer 33

are structures which resemble an onion in cross-section. They are involved in pressure and vibratory sensation. It is not surprising, therefore, that they are most concentrated in the genital area.

Answer 34

resemble a pine-cone and are thought to be involved in fine touch and tactile discrimination. Such receptors are in highest concentration on the distal aspects of the digits, particularly the pulps of the fingers.

Answer 35

Rarely a person is born with a congenital insensitivity to pain, most often with co-existing anhidrosis (an inability to sweat). The condition is caused by mutations in the neurotrophic tyrosine receptor kinase 1 (NTRK1) gene which encodes for the nerve growth factor receptor (NGFR). These children suffer from an enormous number of injuries to the skin and integument, including corneal erosions in >70%. They cannot feel the common danger signs which normally lead to protective responses. Such children have to be examined several times a day for cuts, scrapes, sand stuck in the eye, materials in the skin and other perils common to small children.

Answer 36

Nearly the entire body surface is covered by hair. Areas that specifically are NOT covered with hair include the palms, soles, glans penis, and labia minora. Before many in the audience start objecting, and adding other areas that are “hairless,” understand that we are talking about two different types of hair:

Answer 37

These hairs are large, thick, coarse, pigmented. Terminal hairs, such as those on the scalp, a man’s beard area and possibly chest/back, and the pubic area, begin deep in the dermis at/near the dermal-subcutaneous junction.

Answer 38

These hairs are small, fine, and apigmented. Such hairs are located diffusely on the body, and represented the types of hairs often on the ear, the lateral face of women, and the body in general.

Answer 39

a small, smooth-muscle which, when activated by the autonomic nervous system, brings the hair into a more erect position (“goose bumps”).

Answer 40

secretes an oily substance called sebum onto the hair and indirectly onto the skin surface. The sebaceous glands are more prominent in the “oily” areas of the body, such as the face, neck, and chest and upper back.

Answer 41

It is also common to divide the hair follicle into thirds with the infundibulum representing the upper third, the isthmus being the middle third (from the sebaceous duct to the insertion of the arrector pili), and the matrical area representing the lower third.

Answer 42

suffice to say the follicular unit is derived from the primitive ectodermal germ (PEG). Development of the PEG is an excellent example of embryologic induction (development of eye is the classic example in embryology). Induction means that the underlying mesenchyme, which will become the dermal papillae of the hair, induces formation of the PEG in the overlying fetal skin. Several bulges of the PEG are recognized as being significant: Lower bulge – attachment for arrector pili. Middle bulge – sebaceous gland. Upper bulge – apocrine gland (axillae, groin, or other areas with apocrine glands)

Answer 43

a common “illness” which illustrates some of the important properties of hair growth. The scalp of an adult contains >100,000 hairs, ~85% of which are in anagen (the growth phase), 10-15% in telogen (the resting phase), with the remainder (1-5%) in catagen (transition phase between anagen and telogen). Scalp hairs are terminal hairs. They are thick, usually pigmented, and lie deep in the dermis and subcutis. In androgenic alopecia (“pattern baldness”) the hairs become miniaturized, finer and lie higher in the dermis. Ultimately they come to resemble vellus hairs. In men, this yields the classic fronto-temporal or postero- occipital balding. In women, this leads to thinning of the hair on the crown area. Nearly 50% of both sexes are affected to some degree, although it is not as widely discussed in women. The process is not understood completely, but it is known that conversion of testosterone to 5-dihydrotestosterone is important in promoting this change. For this reason, finasteride, a 5-α-reductase inhibitor, which block this conversion, are used in the treatment of male pattern baldness. Both men and women are also treated with minoxidil, a drug known to promote the anagen phase of hair growth. Neither treatment is entirely satisfactory; research is ongoing.

Answer 44

oil-secreting glands located predominantly in the “oily” areas of the body including the scalp, face, neck, upper chest, and upper back. Sebaceous glands are the classic example of a holocrine gland in that the method of secretion involved entire sebocytes (sebaceous gland cells) being secreted and in the process breaking-down to extrude the contents. Persons vary widely with regard to the basal level of sebum (oil) production. Sex hormones are requisite to sebum secretion. For this reason, disorders associated with the sebaceous glands, such as acne, are not prevalent until after adrenarche (puberty). While it does NOT appear that the glands are innervated by the autonomic nervous system, the exact mechanism that governs sebum production is poorly understood. One of the only medications to significantly decrease sebum production is isotretinoin (Accutane). This rather toxic medicine decreases sebum production by up to 90%, often permanently, yet the mechanism by which it does this is largely unknown.

Answer 45

a ubiquitious disorder of the pilosebaceous unit (the combined hair follicle and oil glands). It does not have single cause but is instead multifactorial. In brief, and with simplification appropriate to this course, plugging of the ostia of the pilosebaceous unit by hyperkeratotic debris leads to accumulation of oil within. Propionibacterium acnes, a normal bacterial commensal, then begins to multiply and converts sebum to pro-inflammatory fatty acids. When the pilosebaceous unit ruptures, the result is the characteristic inflammatory “zit”. Blocked pores themselves constitute comedones, that are further classified to be: open - “black heads” or closed - “white heads”.

Answer 46

what are often referred to as “general sweat glands”. The primary function of the eccrine unit is thermoregulation, which is accomplished through the cooling effects of evaporation of this sweat on the skin surface. Because they are so important in temperature regulation, they are located throughout the body, but are most numerous on the forehead, upper cutaneous lip, and palms/soles. Eccrine glands are a classic example of a merocrine secretion. Merocrine glands secrete WITHOUT either the apocrine blebbing, or holocrine shedding. Eccrine glands develop from an eccrine germ, which is DISTINCTLY different from the primitive ectodermal germ of the follicular unit.

Answer 47

The coiled secretory portion deep in the dermis, The intradermal duct (coiled and straight duct),The intraepidermal portion (called the acrosyringium  

Answer 48

composed of water, sodium, potassium lactate, urea, ammonia, serine, ornithine, citrulline, aspartic acid, heavy metals, organic compounds, and proteolytic enzymes. It is critical to recognize that even though sweating is mediated by the sympathetic portion of the autonomic nervous system it is triggered via acetylcholine secretion. Acetylcholine is a chemical otherwise associated with the parasympathetic nervous system.

Answer 49

The fact that eccrine glands are controlled by the sympathetic nervous system explains why most people sweat more under stress (like public speaking). However, the fact that it is mediated via acetylcholine, a neurotransmitter often associated with parasympathetic responses, explains why certain drugs that increase acetylcholine levels, such as neostigmine, physostigmine and organophosphate-based pesticides, result in increased sweating despite a parasympathetic response systemically. Furthermore, this is why atropine poisoning (a drug which has anticholinergic activity) results in a warm, flushed, but anhidrotic (non-sweating) patient.

Answer 50

Apocrine glands are outgrowths of the upper bulge of the primitive ectodermal germ, a fetal structure which yields the follicular unit. The apocrine glands are located only in the axillary and anogenital area. Although present at birth, they remain small and nonfunctional until after puberty. Specialized variants of apocrine glands include Moll's glands on the eyelids, the cerumen (ear wax) glands of the external auditory canal, and the lactation glands of the breasts. At puberty, hormonal stimulation causes apocrine glands to become functional, and the glands respond mainly to sympathetic adrenergic stimuli initiated by emotional stress.

Answer 51

Apocrine glands consist of a coiled portion deep in the dermis, and a straight duct which traverses the dermis and empties into the hair follicle. The coiled gland consists of one layer of secretory cells around a lumen that is approximately ten times the diameter of its eccrine counterpart. Contractile myoepithelial cells surround the coiled gland. The straight duct runs from the coiled gland to the hair follicle.

Answer 52

The predominant mode of apocrine secretion is decapitation, a process where the apical portion of the secretory cell cytoplasm pinches-off and enters the lumen. Apocrine sweat consists mainly of sialomucin. Although odorless initially, as apocrine sweat comes in contact with normal bacterial flora on the surface of the skin, an odor develops. Apocrine sweat is more viscous and produced in smaller amounts than eccrine sweat. The exact function of apocrine glands is unclear, although they likely represent scent glands.

Answer 53

One disorder of apocrine glands is chromohidrosis (which literally translates into “colored sweat”). Chromhidrosis is exclusively apocrine in origin. Although apocrine glands are found in the genital area, chromhidrosis has been reported mostly only upon the face, axillae, and breast areola. Lipofuscin pigment is responsible for the colored sweat. This pigment is produced in the apocrine gland, and its various oxidative states account for the characteristic yellow, green, blue, or black secretions observed in apocrine chromhidrosis. Approximately 10% of people without true chromohidrosis have colored sweat which is regarded as minor, acceptable, and within the normal range. Apocrine chromhidrosis has no fully satisfactory cure or treatment.

Answer 54

Apoeccrine glands are hybrid sweat glands that are found chiefly in the axilla. Apoeccrine glands may play a role in axillary hyperhidrosis. These hybrid glands have both a small diameter portion, similar to an eccrine gland, and a larger diameter portion that resembles an apocrine gland. Similar to eccrine glands, they respond mainly to cholinergic stimuli, and their ducts are long and open directly onto the skin surface. In some patients they constitute up to 45% of the sweat glands found in the axillary region. The truly impressive thing about apoeccrine glands is that they secrete nearly ten times as much sweat as eccrine glands, making them by far the most productive gland in the dermis.

Answer 55

Localized hyperhidrosis is focal excessive sweating. It may be eccrine, particularly when it involves “clammy hands” or “sweaty feet, or it may be due to apoeccrine glands in the axilla. A positive family history is reported in 30%–50% of patients. Patients with focal hyperhidrosis generally do not sweat during sleep and therefore, most authorities consider it to be a disease of autonomic dysfunction. Although there is no standard definition of hyperhidrosis, less than 1 mL/m2 of sweat production per minute by eccrine glands at rest and at room temperature is considered normal. For practical purposes, any degree of sweating that interferes with the activities of daily living should be viewed as cause for investigation. One way to qualitatively document perspiration, for purposes of tracking treatment, is to apply an iodine solution (1%–5%) to a dry surface. After a few seconds starch is then sprinkled over this same area. The starch and iodine interact in the presence of sweat, producing a purple-black sediment. This purple area identifies the duct of the sweat gland.

Answer 56

There is a wide range of medical and surgical treatments available for patients with focal hyperhidrosis. Initial treatments focus on antiperspirant solutions or anticholinergic medications which decrease eccrine and apoeccrine output. Many patients want to pursue a thoracotomy with transaction of the sympathetic nerve trunk. Often physicians are a bit reluctant as this procedure has a high incidence of mild to severe compensatory hyperhidrosis (a new area of increased sweating), usually involving the trunk and lower limbs. Compensatory hyperhidrosis occurs in up to 86% of patients after thoracotomy. A new and exciting method of treating hyperhidrosis is the use of botulinum toxin A (Botox). When injected into the dermis and subcutis, the toxin blocks the release of acetylcholine from the nerves and thereby blocks the stimulus for sweat production. While it is quite effective, the result is both expensive (generally not covered by insurance) and transient, and for this reason its use is somewhat limited.

Answer 57

common skin disease, which may begin at any age, however, a majority begin before age 5. Prevalence is 7-17.2% in children. Often associated with xerosis (dry skin) and a history of atopy (asthma and allergic rhinitis). There are three stages including infantile, childhood and adult.

Answer 58

must have itchy skin plus three or more of the following: history of involvement of skin creases (or face if patient is under 10 years), personal history of asthma or hay fever (or FH of atopic disease if patient is less than 4 years), history of dry skin within the last year, visible flexural eczema (or face if patient is less than four years old), or onset is under 2 years of age.

Answer 59

barrier disrupted skin, filaggrin mutation, Staphlyococcus aureus acts as a superantigen, elevated IgE, eosinophilia, Th2 type cytokine (IL-4, IL-5, IL-10) immune response produced.

Answer 60

non-immunologically mediated reaction resulting from a direct cytotoxic effect. Either from a singe or repeated exposure to the irritant. There is no specific “test” for irritant dermatitis, irritant contact dermatitis is the most common type of contact dermatitis.

Answer 61

strong irritants damage skin directly even is small amounts contacting the skin for a short time (strong acids and bases). Strong irritants generally carry warning labels and often suggest skin protection such as gloves should be used. Weak irritants are harmless by themselves, but frequent, repeated contact may damage skin (Soap and water, Skin products (even “baby” and “hypoallergenic”), Perfumes, Wool, Raw Foods (meat, fruits, or vegetables held while preparing foods), Body Secretions (feces, urine, saliva, sweat), and Friction).

Answer 62

similar to atopic or allergic contact dermatitis. Clinical history and distribution/ pattern may give clues to diagnosis of irritant contact dermatitis. May burn more than itch.

Answer 63

Requires contact exposure of an allergen, immune response and development of “memory” T cells. Type IV, delayed-type hypersensitivity reaction usually starts 24-48 hours after exposure to the allergen, but it can be delayed longer. Patch testing is the gold standard diagnostic test of allergic contact dermatitis

Answer 64

number one most frequent. Risk factors for sensitization are younger age, female sex and ear piercings. Rate of sensitization in the US is on the rise. Rates of sensitization in Europe are on the decline due to regulation of Nickel in common objects in contact with skin (jewelry, watches, zippers). The dimethlyglyoxime test is used to test metal objects for release of nickel.

Answer 65

the most commonly used topical antibiotic with gram positive and gram negative antibacterial activity. Cross-sensitivity can occur with gentamicin, kanamycin, streptomycin, spectinomycin, tobramycin, paromycin and buitirosin. Sensitivity is more common in patients with atopic dermatitis, stasis dermatitis and otitis externa.

Answer 66

wide spread use has led to increase sensitization. Sensitivity is on the rise (prevalence 1989-90 only 1.5%). Used topically because of nephrotoxicity with systemic administration. Active against gram positive bacteria and spirochetes. Allergy occurs more commonly in patients with chronic skin conditions such as stasis ulcers.

Answer 67

Sharply demarcated patches (thin plaques) with pink or slightly orange-yellow erythema. Characterized by flaky, “greasy” scales. Occurs in infancy and post-puberty when sebaceous glands are active. Occurs in areas rich in sebaceous glands (scalp, face, ears, chest and intertriginous areas).

Answer 68

Commonly involves the scalp, but is more diffuse lesions with finer scale than psoriasis. Facial involvement is usually symmetric over the medial eyebrows, nasolabial folds and ears. Course is chronic relapsing. More extensive and severe disease is seen in HIV pts. Seborrheic dermatitis is also common in Parkinson’s disease

Answer 69

“Cradle cap”. Begins 1 week after birth and may persist for several months. Often starts on the scalp and can become confluent with a thick scale covering most of the scalp. Often seen in the inguinal folds or axillae. Other areas may be involved including the face, posterior ears, neck, trunk and proximal extremities  

Answer 70

Malassezia furfur. A yeast considered normal flora, but yeast number not directly related to seborrheic dermatitis. May be linked to imbalance of normal flora. P. acnes presence is greatly reduced in areas of seb derm. Seb Derm occurs in areas of active sebaceous glands, but not directly related to sebum production. Immune response to M. furfur may be due to production of toxic metabolites by M. furfur

Answer 71

Generally self-limited and mild. Bathing, mild shampoos and emollients. Ketoconazole cream. Hydrocortisone cream

Answer 72

Over the counter dandruff shampoos (zinc, salicyclic acid, tar). Ketoconazole shampoo. Ketoconazole cream. Interval low potency topical steroids. Calcineurin inhibitors (pimecrolimus, tacrolimus)

Answer 73

Chronic venous insufficiency of the lower extremities associated with lower extremity edema.

Answer 74

Dryness. Itching. Allergic contact dermatitis due to use of topical preparations (i.e. topical antibiotics). ACD is found in 58-86% of patients with leg ulcers. Irritant Dermatitis due to wound exudates

Answer 75

Compression. Elevation. Exercise calf muscles. Vascular surgery. Topical steroids. Avoid allergens

Answer 76

Thick, scaly plaques with “lichenification” that result from chronic rubbing and scratching. Topical steroids are first line therapy. Antihistamines can be used for itching. Patients need to be counseled to break the itch-scratch cycle

Answer 77

Common in patients with a history of leg swelling, varicose veins or a history of blood clots. Primarily found on the medial lower leg just above the ankle. Red in color with yellow fibrinous base. Borders irregularly shaped. They may be purulent if infected.

Answer 78

Also called Discoid Eczema. Most often occurs on legs, but can appear on arms and trunk. More common in men age 50+. Round patches may be red, scaly and become crusty. Tends to be stubborn. Moisturization, minimize soap and topical corticosteroids are first line therapy  

Answer 79

Affects up to 2% of the population. Positive FH in 36% of psoriasis pts. Psoriasis impacts quality of life

Answer 80

Chronic Plaque Disease, Guttate, Erythroderma, Pustular Psoriasis, Psoriatic Arthritis Occurs in 5-20% of psoriasis patients  

Answer 81

Epidemiologic studies have shown that in psoriasis patients associated disorders occur more frequently than expected. Arthritis, Crohn’s disease, Persistent low grade inflammation favors the development of insulin resistance, obesity and metabolic syndrome, Metabolic syndrome patients have accelerated atherosclerosis due to inflammation, Cardiovascular Disease (Patients in their 40s with severe psoriasis were more than 2x RR for heart attack than people without skin disease. Mild psoriasis raised the risk of heart attack by 20% for people in their 40s).

Answer 82

Calcipotriol (Vit D3 analog), Corticosteroids, Topical Retinoids, Phototherapy, UVB/NBUVB, PUVA  

Answer 83

Methotrexate, Cyclosporin, Systemic Retinoids, Biologics, Anti-T lymphocyte, Anti-TNF alpha

Answer 84

10-20% in children are drug induced. 50-70% in adults are drug-induced. Responsible drugs: Aminopenicillins, Sulfonamides, Cephalosporins, Anticonvulsants, and Allopurinol

Answer 85

Differential diagnosis = Viral exanthema. (EBV, Enterovirus, Adenovirus, Early HIV, Parvovirus B19, CMV). Viral infections enhance the risk of drug eruption. Almost 100% of pts with infectious mononucleosis will get an exanthematous eruption if given ampicillin. HIV pts are more susceptible to drug eruptions  

Answer 86

Discontinue the offending medication. Eruption will generally resolve spontaneously after 1-2 weeks. Supportive therapy for pruritus with topical steroids and anti-histamines. However, it can take up to 3 months to completely resolve

Answer 87

Histology: Shows dermal edema with eosinophils +/- neutrophils. Treatment = Antihistamines. Acute (< 6 weeks). Acute urticaria represents an immediate type I hypersensitivity reaction mediated by IgE antibodies. First exposure generates IgE antibodies. Upon re-exposure, antibody binds to IgE on mast cells and basophils causing degranulation with release of mediators such as histamine. Chronic (> 6 weeks)

Answer 88

Nodular (75%) (micronodular and pigmented (6%)), Superficial (15%), Infiltrative (5%), Sclerosing (morpheaform) (3%)

Answer 89

Skin cancers often don’t cause symptoms until they become quite large. Then they can bleed or even hurt. Basal cell carcinomas often appear as flat, firm, pale areas or as small, raised, pink or red, translucent, shiny, waxy areas that may bleed after minor injury. You might see one or more abnormal blood vessels, a depressed area in the center, or blue, brown, or black areas. Large BCCs may have oozing or crusted spots.

Answer 90

Basal cell cancer begins in the lowest layer of the epidermis, called the basal cell layer. Basal cell carcinomas arise from pluripotential cells due to mutations in the hedgehog pathway. Most commonly mutations inactivate the patched 1 gene, a tumor suppressor gene. Other mutations may activate smoothened or hedgehog.

Answer 91

About 3 out of 4 skin cancers are basal cell carcinomas. They usually begin on areas exposed to the sun such as the head and neck. Basal cell carcinoma was once found mostly in middle-aged or older people. Now it is also being seen in younger people, perhaps because people are spending more time in the sun without protecting their skin. Basal cell carcinoma tends to grow slowly. It is very rare for a basal cell cancer to metastasize. But if it is not treated, it can grow into nearby areas and invade the bone or other tissues beneath the skin. Vismodegib, a small-molecule inhibitor of smoothened, was approved in January 2012 for the treatment of locally advanced and metastatic basal- cell carcinomas. After treatment, basal cell carcinoma can recur in the same place on the skin. Also, new basal cell cancers can start other places on the skin. Within 5 years of being diagnosed with basal cell cancer, 35% to 50% of people develop a new skin cancer.

Answer 92

Hypertrophic, Atrophic, Acantholytic, Lichenoid, Cutaneous Horn, and Actinic Cheilitis

Answer 93

Actinic keratoses (Intraepidermal neoplasia I) are the most common pre-malignant skin lesion. The actinic keratosis (AK) is the earliest identifiable lesion that can eventually develop into an invasive squamous cell carcinoma (SCC). AKs are diagnosed in 14% of all visits to dermatologists, following only acne and dermatitis in frequency. The nomenclature for AKs is controversial; some consider them "pre-cancerous" and others consider them to be a SCC confined to the lower portion of the epidermis. Actinic keratoses typically occur in fair-skinned individuals. In various northern hemisphere populations, 11-25% of adults have at least one, compared to 40-60% of adult Australians who live closer to the equator. One prospective study estimates that one AK/1000/year transforms into SCC, while retrospective studies predict that from 5-20% of all untreated AKs will progress to SCC. AK’s are typically produced by ultraviolet radiation, but ionizing radiation, arsenic, or polycyclic hydrocarbon exposure may also cause them. At least two prospective studies have demonstrated that sunscreen reduces the likelihood of developing more AKs. Actinic keratoses are distributed in areas of increased sun exposure and are characterized by hyperkeratosis and erythematous papules, which are often easier to palpate than to visualize.

Answer 94

includes cryotherapy, 5-fluorouracil (topical), imiquimod (topical), diclofeac (topical), photodynamic therapy (PDT), and ingenol mebutate (topical)).

Answer 95

liquid nitrogen technique (196 C). indicated for discrete limited number of lesions.

Answer 96

anti-neoplastic effect via thymidine synthase and subsequently DNA synthesis. Indicated for numerous lesion that are ill-defined. It is a skin irritant.

Answer 97

Immunomodulating, Toll-like receptor 7 agonist. Indicated for numerous lesion that are ill-defined. It is a skin irritant.

Answer 98

Nonsteroidal anti-inflammatory drug (NSAID), inhibitor of cyclo-oxygenase- 2 (COX-2), resulting in a reduction of prostaglandin synthesis. Indicated for numerous lesion that are ill-defined. It is less effective than other treatments.

Answer 99

Topical 5-aminolevulinic acid accumulates preferentially in dysplastic cells, upon exposure to irradiation of appropriate wavelength of light, oxygen free radicals are generated and cell death ensues. Indicated for numerous lesion that are ill-defined. It is less available than other treatments.

Answer 100

Ingenol mebutate is the active agent in the sap of the Australian plant Euphorbia peplus. The mechanism of action by which Picato gel induces cell death in treating actinic keratosis lesions is unknown. Indicated for numerous lesion that are ill-defined. It is a skin irritant. Course of therapy only 2-3 days.

Answer 101

Squamous cell carcinoma may appear as growing lumps, often with a rough surface, or as flat, reddish patches that grow slowly. Both BCCs and SCCs may develop as a flat area showing only slight changes from normal skin.

Answer 102

This type of cancer begins in the upper part of the epidermis and accounts for about 1 to 3 out of 10 skin cancers. Squamous cell carcinomas are the second most common cutaneous malignancy. SCCs also appear on sun exposed skin such as the face, ear, neck, lips, and backs of the hands. SCC can also begin within scars, skin ulcers or other areas of chronic injury and an SCC in these situations is called a Marjolin’s ulcer. Less often, SCC forms in the skin of the genital area. Squamous cell carcinomas are more likely to invade fatty tissues just beneath the skin. They are also slightly more likely to spread to lymph nodes or distant parts of the body than are basal cell carcinomas, although this is still not common. SCCs occur much more commonly in immunosuppressed patients, especially organ transplant patients.

Answer 103

includes Squamous cell carcinoma in situ (Bowen’s disease), Keratoacanthoma, and Invasive squamous cell carcinoma.

Answer 104

the earliest form of squamous cell skin cancer. “In situ” means that the cancer is only in the epidermis where it began. Bowen disease looks like scaly, reddish patches that may be crusted. The major risk factor for Bowen disease is too much exposure to the sun. Bowen’s disease in the anal and genital skin is often linked to human papilloma virus that causes genital warts. Clinically, SCC in situ appears as an erythematous, hyperkeratotic patch or plaque which is sharply demarcated from the surrounding skin. Histologically, there is loss of the normal progression from basal layer to granular layer with atypia and pleomorphism of keratinocytes extending throughout the entire epidermis.

Answer 105

A squamous cell carcinoma. They usually appear as a solitary lesion in sun exposed skin. They can develop fairly quickly over 6 to 8 weeks with sizes of 1-3 cm. Histopathologically, there is a cup-shaped invagination of the epidermis with keratin- filled central crater. Most cells are large with pale, eosinophilic “glassy” cytoplasm.

Answer 106

Occurs typically as a hyperkeratotic papule with variable size and thickness as well as indistinct margins. SCC is typically found in areas of chronically sun damaged skin. Metastasis occurs in 0.3-5%, but is more common in SCC of the lip (10-30%) and may also be more common in the external ear. Perineural invasion is another marker for aggressive lesions.

Answer 107

The exact number of basal and squamous cell carcinomas is unknown because cases are not reported. It could be that there are at least as many non-melanoma skin cancer cases found each year, as all other cancers combined (more than 1 million each year). Most of the cancers are basal cell – about 800,000 to 900,000. Squamous cell cancer occurs less often – perhaps about 200,000 to 300,000 cases per year. Men get these cancers about twice as often as women. People do not often die of these cancers. About 1,000 to 2,000 people die of non- melanoma skin cancer (NMSC) each year in this country. Most people who die are older and have not received treatment for their cancers soon enough. Other people likely to die of skin cancer are those whose immune systems are suppressed. These are most often people who have received organ transplants.

Answer 108

Ultraviolet (UV) Light, fair skin, gender, chemicals, radiation, having a skin cancer, phototherapy, genetic skin diseases, immunosuppression, HPV infection, and smoking.

Answer 109

thought to be the major risk factor for most skin cancers and sunlight is the main source of UV, which can damage DNA in keratinocytes. Tanning lamps and beds are another source of UV radiation. People with too much exposure to light from these sources are at greater risk for skin cancer. SCC incidence correlates best with total, lifetime ultraviolet radiation exposure, while BCC occurrence corresponds better with intermittent sunlight exposure and severe sunburns. The amount of UV exposure depends on the strength of the light, how long the skin was exposed, and whether the skin was covered with clothing and sunscreen. Many studies also show that being exposed at a young age as an added risk factor. People who live in places with year-round, bright sunlight have a higher risk. Rates of NMSC increase with decreasing latitude, as SCC doubles for each 8-10 degree decline. For example, the risk of skin cancer is twice as high in Arizona compared to Minnesota. The highest rate of skin cancer in the world is in Australia. Spending a lot of time outdoors without wearing enough clothing and sunscreen increases your risk.

Answer 110

The risk of skin cancer is much higher for whites than for dark-skinned African Americans. This is because melanin offers some protection from UV radiation. People with dark skin have more melanin. People with fair skin that freckles or burns easily are at especially high risk.

Answer 111

Men are 2 times as likely as women to have basal cell cancers and 3 times as likely to have squamous cell cancers of the skin. This could be because they spend more time outdoors.

Answer 112

Exposure to large amounts of arsenic, a heavy metal used in making some insecticides, increases the risk of skin cancer. Workers exposed to industrial tar, coal, paraffin, and certain types of oil may also have an increased risk.

Answer 113

People who have had radiation treatment have a higher risk of getting skin cancer in the area that was treated. This can be a problem for children who have had cancer treatment. Almost all of these cancers are basal cell.

Answer 114

After developing an initial BCC or SCC, patients have approximately a 50% chance of developing another NMSC within 5 years.

Answer 115

Psoralen and ultraviolet light treatments (PUVA) given to some patients with skin disease such as psoriasis can increase the risk of getting squamous cell skin cancer and perhaps other skin cancers as well.

Answer 116

Basal Cell Nevus Syndrome and Xeroderma pigmentosum

Answer 117

 Organ transplant patients have an increased risk of skin cancer due to their medical immunosuppression. The skin cancers in people with weakened immune systems grow much faster and are more likely to be fatal.

Answer 118

A small number of skin cancers seem to be linked to infection with human papilloma virus (HPV). This group of viruses can cause warts different from the common type of warts that people get on their hands and feet. The HPV-related warts appear in the genital and perianal skin. They are linked to skin cancers in these areas.

Answer 119

Smoking is a risk factor for squamous cell skin cancer, but not for basal cell cancer.

Answer 120

5-fluorouracil (Topical), Imiquimod (Topical), Cryotherapy, Curettage (usually with electrodesiccation), Excision, Mohs micrographic surgery technique, and Radiotherapy

Answer 121

Looped blade scrapes tumor away from adjacent normal skin, indicated for nodular BCC and superficial BCC. It is operator dependent and is a blind technique (no tissue for histologic examination). Leaves an open wound.

Answer 122

Excise clinically apparent tumor and a margin of clinically normal-appearing skin. Indicated for well-circumscribed tumors that are non-aggressive. Sacrifices tissue to obtain acceptable cure rates (minimum of 4 mm margins). Standard “bread loaf” tissue sectioning may miss microscopic tumor at the margin due to sampling.

Answer 123

Skin sparing Removal of clinically apparent tumor with a thin rim of normal appearing skin. Nearly the entire margin is evaluated with frozen section techniques. Tissue is mapped microscopically. Indicated for aggressive, recurrent, and perineural tumors. It is costly and time intensive.

Answer 124

Radiation, fractionated over several weeks. Indicated for non-aggressive, poor surgical candidates (debilitated and elderly), patients who refuse surgery of a lesion, and proximity to a vital structure.

Answer 125

accounts for about 3% of skin cancer cases but causes a large majority of skin cancer deaths. The American Cancer Society estimates that about 59,940 new melanomas will be diagnosed in the United States during 2007. The number of new melanomas diagnosed in the United States is increasing. Incidence rates for melanoma increased sharply at about 6% per year in the 1970s. Since then, however, the rate of increase slowed to a little less than 3% per year. About 8,110 people in the United States are expected to die of melanoma during 2007. After increasing for several decades, the death rate for melanoma has been stable since 1990 in white men and has been decreasing since 1988 in white women. Melanoma is more than 10 times more common in whites than in African Americans. It is slightly more common in males than in females. Unlike many other common cancers, melanoma has a wide age distribution. It occurs in younger as well as older people. Although rates continue to increase with ageing and are highest among those in their 80s, melanoma is not uncommon even among those younger than 30. In fact, it is one of the more common cancers in adolescents and young adults.

Answer 126

Superficial Spreading 70%, Nodular 15%, Lentigo Maligna Melanoma 5%, and Acral Lentiginous 10%

Answer 127

may arise within a previously existing nevus or dysplastic nevus, but approximately 70% of the time, they arise de novo. Superficial spreading melanomas typically show the ABCD’s of melanoma (Asymmetry, Border irregularity, Color variegation and Diameter greater than 6mm). Many people as look at E for evolution or change. A new tool used in diagnosing melanoma is looking for the “Ugly Duckling”, or the mole(s) that look different from their neighboring moles. If neglected, the depth of tumor invasion can continue to increase; a clinical correlate would be the development of nodularity within the melanoma. Nodular melanoma classically does not have a macular or plaque phase and presents as a blue or black papule or nodule. The superficial spreading and nodular types of melanoma together account for approximately 80% of all melanomas. Both types occur most commonly in patients with lighter skin phenotypes, and may occur anywhere, but have a predilection for the upper back in men and women and the lower legs in women. Risk factors for developing these variants of melanoma include a family history of melanoma (with or without the presence of multiple dysplastic nevi), the presence of numerous common acquired nevi, and a history of blistering sunburns. The other subtypes of melanoma, lentigo maligna melanoma and acral lentiginous melanoma, are not correlated with intense, intermittent sun exposure. Lentigo maligna melanoma accounts for approximately 5% of all melanomas and is most commonly seen at sites of maximum sun exposure in patients with obvious photodamage, e.g., the face, hairless ("bald") scalp, extensor forearms and upper trunk. Acral lentiginous melanomas comprise 3-8% of all melanomas and by definition arise on the volar skin of the palms or soles and the nailbeds. Acral lentiginous melanomas have no known correlation with sun exposure and are the most common form of melanoma in African-Americans, Asians, and Hispanics. The most important indicator of prognosis for all subtypes of melanoma is the Breslow depth, which is the maximal thickness of tumor invasion as measured by an ocular micrometer, from the top of the granular layer of the epidermis to the base of the neoplasm. Breslow depth is recorded in millimeters with lesions less than 1.0 mm having an excellent prognosis with infrequent metastases and melanomas thicker than 4mm having a rather poor prognosis with a 5-year survival of approximately 50%. The most common sites of local and/or regional metastases are the draining lymph node basins and the skin between the primary site and these lymph nodes whereas the most common sites of systemic metastases are the lung, liver, brain, and gastrointestinal tract.

Answer 128

the most important factor in determining prognosis of melanoma. Ulceration, regression and mitotic index are other factors used in determining the aggressiveness of the tumor.

Answer 129

Another system, called the Clark level, describes how far a melanoma has penetrated into the skin instead of actually measuring it. The Clark level of a melanoma uses a scale of I to V (with higher numbers indicating a deeper melanoma) to describe whether: the cancer stays in the epidermis (Clark level I), the cancer has begun to invade the upper dermis (Clark level II), the cancer involves most of the upper dermis (Clark level III), the cancer has reached the lower dermis (Clark level IV), and the cancer has invaded to the subcutis (Clark level V)

Answer 130

has a major effect on a person's outlook for survival. The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Keep in mind that many of these patients live much longer than 5 years after diagnosis. Five-year rates are used to produce a standard way of discussing prognosis. The following survival rates are based on a study of more than 40,000 patients who were diagnosed between 1988 and 2001. There are ranges of survival rates within some of the stages because they include different T and N categories. Keep in mind that these numbers are merely statistics - they do not necessarily apply to any person's particular situation. Some people may do better or worse than what would be expected by the numbers below, based on a number of factors other than the stage of the melanoma.

Answer 131

The 5-year survival rate is around 99%. The 10-year survival is around 97%.

Answer 132

The 5-year survival rate is around 92%. The 10-year survival is around 86%.

Answer 133

The 5-year survival rate is around 78%. The 10-year survival is around 66%.

Answer 134

The 5-year survival rate is around 68%. The 10-year survival is around 59%

Answer 135

The 5-year survival rate is around 56%. The 10-year survival is around 48%

Answer 136

This was a new stage when the study was done, so 5- and 10-year survival rates were not available for this group. The rates would most likely fall in between the stages above and below.

Answer 137

The 5-year survival rate ranges from around 50% to around 68%. The 10- year survival ranges from around 44% to around 60%.

Answer 138

The 5-year survival rate ranges from around 27% to around 52%. The 10- year survival ranges from around 22% to around 37%.

Answer 139

The 5-year survival rate for stage IV melanoma is about 18%. The 10-year survival is 14%. It is higher if the spread is to skin or distant lymph nodes rather than to other organs.

Answer 140

Ultraviolet (UV) radiation damages DNA. Most UV radiation comes from sunlight, but some may come from manmade sources such as tanning booths. A mutation in the BRAF gene is found in many melanomas. This change is not inherited; it seems to occur during the development of the melanoma. Although most moles never turn into a melanoma, some do. There are some DNA changes that transform benign nevus cells into melanoma cells. But it is still not known exactly why some moles become cancerous or why having many nevi or dysplastic nevi increases the risk of developing melanoma.

Answer 141

Melanoma in situ is treated with wide local excision with 0.5 cm margins. Wide local excision with 1 cm margins is the treatment of choice for tumors < 1mm thick. If tumors are > 1 mm in Breslow depth, often they ar referred for sentinel lymph node biopsy at the time of wide local excision. Sentinel lymph node biopsy may help with staging and prognosis of melanoma, but has not been shown to improve survival. Tumors thicker than 2mm in depth are often excised with a 2 cm margin. Adjuvant therapy may be used for tumors > 4mm thick or if lymph nodes are positive.

Answer 142

includes immunotherapy, signal transduction inhibitors, chemotherapy, and palliative local therapy.

Answer 143

Ipilimumab is a human monoclonal antibody that blocks the activity of cytotoxic T-lymphocyte antigen 4 (CTLA-4), blocking the function of CTLA- 4 as a down regulator of T-cell activation. It is approved for the treatment of unresectable or metastatic melanoma and supported by two prospective, randomized, international trials, one each in previously untreated and treated patients. Interleukin-2 response with high-dose regimens generally ranges from 10% to 20%. Approximately 4% to 6% of patients may obtain a durable complete remission and be long-term survivors 2. Signal transduction inhibitors. Vemurafenib is an orally available, selective BRAF (V-raf murine sarcoma viral oncogene homolog B1) inhibitor that is approved by the FDA for patients with unresectable or metastatic melanoma that tests positive for the BRAF V600E mutation. Because improvement with BRAF inhibitors is often temporary, newer approaches such as combination with a MEK inhibitor is currently under investigation.

Answer 144

Because stage IV melanoma is very hard to treat with current therapies, patients may want to think about taking part in a clinical trial. Clinical trials of new chemotherapy drugs, new methods of immunotherapy or vaccine therapy, and combinations of different types of treatments may benefit some patients. Even though the outlook for patients with stage IV melanoma tends to be poor overall, a small number of patients have responded extraordinarily well to treatment or have survived for many years after diagnosis.

Answer 145

asymmetry (one half unlike the other half), border (irregular, scalloped or poorly circumscribed border), color (varied from one area to another; shades of tan and brown, black; sometimes white, red or blue), and diameter (While melanomas are usually greater than6mm in diameter (the size of a pencil eraser) when diagnosed, they can be smaller. If you notice a mole different from others, or which changes, itches, or bleeds (even if it is small) you should see a dermatologist)

Answer 146

Endothelial malignancy triggered by HHV-8. Slowly progressive. Incidence 0.05 per 100,000 population in the USA Three clinical Subtypes. Classic– Occurs primarily in elderly men of Eastern European descent. Lymphadenopathic– Aggressive form primarily in equatorial Africa – Affects young men and is rapidly fatal. AIDS – Associated. Incidence is declining with better anti-retroviral therapy against HIV

Answer 147

Circumscribed change in skin color that is flush with the surrounding skin. Lesion is <1.0 cm in diameter. Examples include Solar lentigo and Traumatic purpura

Answer 148

Circumscribed change in skin color that is flush with the surrounding skin. Lesion is ≥1.0 cm in diameter. Examples include Café au lait spot and Vitiligo.

Answer 149

A solid or cystic elevation <1.0 cm in diameter. Examples include Acne and Eruptive xanthoma

Answer 150

A solid or cystic elevation >1.0 cm but <2.0 cm in diameter. Examples include Dermato-fibroma

Answer 151

A solid or cystic elevation >2.0 cm in diameter. Examples include Follicular cyst

Answer 152

An elevated lesion that is >1.0 cm in diameter. Examples include Psoriasis.

Answer 153

Desiccated, thin plates of cornified epidermal cells that form flakes on the skin surface. Ichthyosis

Answer 154

Circumscribed, flat-topped, firm elevation of skin with a well-demarcated and palpable margin. Urticaria

Answer 155

Circumscribed, elevated lesion containing clear serous or hemorrhagic fluid that is <1 cm in diameter. Contact dermatitis and Herpes simplex

Answer 156

Circumscribed, elevated lesion containing clear serous or hemorrhagic fluid that is >1 cm in diameter. Bullous pemphigoid

Answer 157

A vesicle containing purulent exudate. Folliculitis

Answer 158

A depression from the surface of the skin with underlying loss of epidermal or dermal substance. Lichen sclerosis et atrophicus

Answer 159

A depression from the surface of the skin with a loss of all or part of the epidermis. Burn and Ruptured bulla

Answer 160

A depression from the surface of the skin with a loss of the entire epidermis and at least some of the dermis. Ecthyma

Answer 161

Dry, leathery thickening of the skin with exaggerated skin markings

Answer 162

includes hemangioma and cherry angioma

Answer 163

includes port wine stain

Answer 164

sebaceous hyperplasia and nevus sebaceous

Answer 165

dermatofibroma

Answer 166

seborrheic keratosis and actinic keratosis

Answer 167

cherry red, smooth-topped papules on the skin containing an abnormal proliferation of blood vessels. They are the most common kind of angioma. distribution is primarily truncal. Typically there are multiples, up to many hundreds. They are primary lesions, usually 1-4mm in size, and are occasionally pedunculated. There are no complications except for in the case of trauma.

Answer 168

superficial electrodesiccation is best for small lesions and may require local anesthesia. Liquid nitrogen/ fluoroethyl refrigerant spray followed by curettage. Shave biopsy. Pulse dye laser work best for small lesions. Other vascular lasers.

Answer 169

Strawberry (capillary) hemangiomas are benign vascular proliferations and the most common benign tumor of childhood. They appear by 2 months of age, with 1/3 present at birth. The grow rapidly over the first year of life, then they involute slowly at about 10% per year, so that 50% have resolved by age 5 and 90% have resolved by age 9.

Answer 170

Periocular hemangiomas may interrupt the visual field and cause astigmatism or more severe ocular complications. Other troublesome locations include the lip, nasal tip, ear, breast and anogenital area. Large hemangiomas may distort normal tissue and interfere with function. Ulcerated hemangiomas are treated to prevent infection and reduce pain. Multiple hemangiomas may be a sign of diffuse neonatal hemangiomatosis with visceral hemangiomas most often found in the liver, GI tract, lungs and CNS. Other more severe complications can occur with large hemangiomas including Kasabach-Merritt syndrome (a consumptive thrombocytopenic coagulopathy) and high output congestive heart failure. PHACES syndrome (Posterior fossa malformations, Hemangioma, Arterial anomalies of the aortic branches, Cardiac defects and coarctation of the aorta, Eye anomalies and Sternal defects and supraumbilical raphe)

Answer 171

There is a dermal proliferation of capillary-sized endothelial cell-lined vessels. The cells stain with placenta-associated vascular markers including GLUT-1. One theory is that hemangiomas arise from embolized placental cells or from invading angioblasts that differentiate toward a placental phenotype.

Answer 172

Since they involute spontaneously, no treatment is necessary in most cases. However, some hemangiomas may necessitate therapy because of their size, location or associated complications. Treatment options include local wound care, laser surgery, topical, intralesional or systemic steroids. Interferon α has been used to treat severe hemangiomas, but spastic diplegia can occur resulting in persistent neurologic impairment.

Answer 173

Port wine stains are vascular malformations. Unlike hemangiomas of infancy, they do not resolve spontaneously. Over time, the vascular malformation may worsen, changing from a pink patch to a thicker purple plaque with nodularity. Most port wine stains are present at birth and grow in proportion to the growth of the individual. Port wine stains of the face follow the distribution of the trigeminal nerve. Port wine stains over the midline of the dorsal, lumbrosacral or nape may be a sign of occult spinal dysraphism. Port wine stains may be associated with systemic abnormalities. A complete list of these syndromes is beyond the scope of this lecture, however one example is Sturge Weber syndrome (SWS). 10-15% of capillary malformations in a V1 distribution are associated with the ocular and neurologic abnormalities of SWS which include glaucoma, seizures and developmental delay among other symptoms.

Answer 174

Ectatic capillaries within the dermis are lined by a flat continuous endothelium.

Answer 175

Vascular lasers.

Answer 176

A hamartoma that most commonly presents as a papillomatous, yellow-orange linear plaque on the face or scalp. Lesions on the scalp are associated with alopecia. Rapid growth occurs at puberty with enlargement of sebaceous glands and epidermal hyperplasia.

Answer 177

Observation (no treatment), surgical excision, or carbon dioxide laser ablation

Answer 178

Epidemal nevus syndrome (neurologic abnormalities). Epithelial neoplasms occur in 10-30% (trichoblstoma, syringocystadenoma papilliferum, basal cell carcinoma)

Answer 179

Common benign tumor of oil gland. Increasing frequency after middle age. May be sunlight induced. Distribution is on the face>trunk>extremities. Primary lesion- 1-6 mm yellowish-white papule (globules) with central dell. May be component of Muir-Torre syndrome

Answer 180

No treatment necessary, cosmetic is the only issue. Excision biopsy is rarely done and causes a linear scar. Deep curettage causes a white scar that can be depressed. Electrodessication w/wo curettage. Trichloroacetic acid (50%) for 3-5 seconds. Liquid nitrogen cryotherapy has a high recurrence rate. Lasers are expensive.

Answer 181

All physicians should be able to recognize these benign skin growths. Skin tags commonly occur in areas of rubbing including the neck, axilla and infra-mammary area in women. No treatment is necessary for these common skin growths as they are benign with no malignant potential. They can, however, be removed if bleeding from irritation or rubbing on clothing. The most common way to remove these lesions is by freezing (cryosurgery) with liquid nitrogen or by cutting them off.

Answer 182

Dermatofibromas (benign fibrous histiocytoma) are the second most common fibrohistocytic tumor of the skin. (Skin tags are the most common). They appear as brown, firm papules and usually range from 3-10 mm in size. They occur in adults, as they are acquired, and are most common on the legs. The “dimple sign” is characteristic, which is demonstrated by pinching the lesion lightly and causing a slight downward movement of the tumor. Larger and enlarging lesions may represent the malignant version, dermatofibrosarcoma protuberans (DFSP).

Answer 183

Generally no therapy is recommended for dermatofibromas, as the scar for removal may be more noticeable than the original lesion. However, they may be biopsied or excised to rule out a melanocytic lesion. Untreated, dermatofibromas will remain stable in size.

Answer 184

The overlying epidermis shows elongated rete ridges and increased melanin in the basal layer of the epidermis. In the dermis are a mixture of histiocytic cells and spindle cells arranged in a whorled pattern. Collagen bundles become entrapped by the proliferating cells and the border is ill-defined.

Answer 185

Seborrheic keratoses are oval, slightly raised, light brown to black papules or plaques. They rarely exceed 3 cm in diameter and are most commonly located on the chest and back. They are also commonly found on the scalp, face, neck and extremities, but spare the palms and soles. The onset is usually in the fourth or fifth decade with a gradual increase in number. Some patients may have hundreds of lesions.

Answer 186

includes dermatosis papulosa nigra, stucco keratosis, and sign of leser-trelat

Answer 187

a subtype of seborrheic keratosis. small, pigmented seborrheic keratoses usually occurring on the face of people with Fitzpatrick skin type V or VI.

Answer 188

a subtype of seborrheic keratosis. Multiple small, 1-5 mm, hyperkeratotic papules found around the ankles, feet, forearms and dorsal hands which histologically resemble seborrheic keratoses.

Answer 189

a subtype of seborrheic keratosis. Paraneoplastic syndrome reported to occur with the sudden onset of multiple seborrheic keratoses, associated with adenocarcinoma of the stomach in 60% and also associated with other common malignancies.

Answer 190

Papillary epidermal hyperplasia (papillomatosis) with proliferation of basaloid cells, laminated hyperkeratosis and horn pseuodocysts.

Answer 191

Nevi = Moles, Melanoma, Ephelides = Freckles, Lentigo = Sun Spots, and Café au lait macule  

Answer 192

“Moles”

Answer 193

Junctional nevus, Intradermal nevus, Compound nevus, Halo nevus, Acral nevus, Blue nevus, Spitz nevus, Pigmented spindle cell nevus, Dysplastic nevus, and Congenital nevus

Answer 194

includes intradermal nevus, junctional nevus, and compound nevus

Answer 195

Nevi are classified depending on the location of the melanocytic nests. In junctional nevi, the nevus cells are at the dermal epidermal junction just above the basement membrane zone of the epidermis; the clinical correlate is a darkly pigmented flat or minimally elevated nevus. As nevi mature, the nests of melanocytes gradually are assimilated into the dermis; they are then classified as compound nevi when the nests are present at the dermal epidermal junction and within the dermis or as intradermal nevi when the nests are exclusively within the dermis. As the nests descend, they become uniformly smaller and are composed of smaller-sized melanocytes which produce less pigment; the surrounding stroma becomes infiltrated by fibrofatty tissue.

Answer 196

dermal proliferation of melanocytes that produce abundant melanin. Blue color is an optical effect where longer wavelengths are absorbed and shorter wavelengths are reflected back (Tyndall effect). Congenital (1:3000) or acquired (up to 4% of adults). Most common in Asians and whites, uncommon in blacks. Primary lesion is blue to blue-gray to blue-white papule or nodule. Size is 1 mm to 2 cm. No treatment (Common option for unchanging lesions). Malignant blue nevus are extremely rare. Surgical removal: Punch or Excisional biopsy.  

Answer 197

May be solitary or multiple. May affect any cutaneous surface. Primary lesion identical to acquired nevi only differ in size, greater than 1 mm to huge (i.e. bathing trunk nevi). Presence of dark hairs of no clinical significance. Complications when present on the head, neck, posterior midline, causing cranial and or leptomeningeal melanocytosis. Congenital nevi is present in 1% of newborns. Sizes range from small (20 cm diameter). Treatment is a highly controversial area. Elective surgical for excision, but most authorities do not recommend. Recommended by some if clinically feasible. Dermabrasion is performed by a minority of authorities. Risk for Melanoma: Medium to Large Congenital nevi > 10 cm (Occur in 1:20,000 newborns). The calculated potential for malignant melanoma is about 1% per year in large congenital nevi (>20 cm diameter). Malignant melanoma in congenital nevi 50% appear in first 3 years and 60% appear in first decade

Answer 198

(atypical nevi, Clark’s nevi, nevi with disordered architecture and cytologic atypia) are a subgroup of nevi, which have an irregular outline, variable pigmentation, indistinct borders, and can be larger than 6mm in diameter. Often described as having a "fried-egg" appearance, they typically have a dome-shaped central brown papular component surrounded by a flatter zone of light brown or tan pigmentation. When multiple dysplastic nevi are present in a patient with a family history of melanoma, they herald an increased risk for the development of melanoma in that patient. The presence of a single or few dysplastic nevi outside the context of a family history of melanoma may or may not portend an increased risk for that patient. They show disordered histological architecture, typified by less circumscription of the nevus cell nests and extension of the junctional nests beyond the intradermal component. Dysplastic nevi also show an increased number of single melanocytes in the basal layer of the epidermis; pleomorphism of cells; and nests that vary in size, shape, and spacing. The upper dermis usually shows fibrosis and contains a host response of lymphocytes.

Answer 199

The criteria for FAMM syndrome are as follows: The occurrence of malignant melanoma in 1 or more first- or second-degree relatives. The presence of numerous (often >50) melanocytic nevi, some of which are clinically atypical. Many of the associated nevi showing certain histologic features. Germline mutations in 3 genes have been linked to a subset of hereditary melanomas and FAMM syndrome, CDK2NA mapped to 9p21, CDK4 mapped to 12q14, and CMM1 mapped to 1p. Could be polygenetic or multifactorial. These mutations are found in some but not all atypical nevi.

Answer 200

anti-microbial peptides include α-defensins (hNP1, hNP2), β-defensins (hBD-1, -2, -3, -), a cathelicidin (hCAP-18), psoriasin, and RNase7.

Answer 201

small, cationic, cysteine-rich peptides that differ in their disulfide-bond pairing and tissue distribution. α-defensins are primarily found in neutrophils in the small intestine although small amounts are found in keratinocytes. All four β-defensins that are found in keratinocytes demonstrate anti-microbial activity against viruses, gram-positive bacteria, gram-negative bacteria and yeast. Different β-defensins demonstrate variable activity against specific microbial organisms (for example hBD3 is highly effective against Staphylococcus aureus while hBD2 demonstrates minimal activity against this organism).

Answer 202

a small, cationic peptide that possesses cysteine protease inhibitory activity. This results in a broad spectrum of anti-microbial activity to include viruses although it demonstrates minimal activity against some microbial species (e.g., staphylococcal species). The importance of this molecule has been clearly demonstrated in knockout mice were the absence of this peptide results in increased skin infections. Psoriasin and RNase 7 appear to be important to protect the skin against fecally-derived gram-negative bacteria.

Answer 203

An important defensive function of the skin is the modulation of changes in skin pH which is normally 4.5 to 5.0 in the outer stratum corneum. In general the normal flora grows best at an acidic pH while many pathogenic bacteria such as Staphylococcus aureus grow best at a neutral pH that is primarily maintained in the skin by lipids and sodium- proton exchange. It is believed that the absence of sebaceous-derived lipids in prepubertal children account for the susceptibility to dermatophyte infections of the scalp.

Answer 204

One of the major functions of skin is that of protective or even defensive against potentially harmful microorganisms including viruses, bacteria, fungi, parasites, and arthropods. While it is intuitively obvious that the skin presents a daunting physical barrier to pathogenic microorganisms, it can also shed itself of organisms by the process of desquamation. In addition to the physical aspect, the epidermis has in innate defense response composed of large numbers of anti-microbial lipids, toll-like receptors, peptides and chemokines. The skin is the first-line defense against the entry of microorganisms into the body and this is accomplished by a combination of pH, physical barriers, desquamation and superficial innate defensive functions. Of importance is the fact that some of these defensive functions can be compromised by external agents (e.g., alkaline soaps that modify the skin pH). Once the skin is breached by a microorganism, a variety of internal mechanisms (e.g., inflammatory cells, immunoglobulins, etc.) provide further defense.

Answer 205

A prevalence of up to 10% in children between two in 12 years of age. In the United States an estimated 20 million people have genital HPV infections at any time. Infections acquired through small breaks in the skin. Person-two-person contact (e.g., sexual intercourse, birth). Fomites (e.g., towels, bathroom floors) can also transmit the virus.

Answer 206

Belongs to the papovavirus group (Papovaviridae). Genomes of 79 HPV types have been fully characterized- partial DNA sequences suggest at least 130 HPV genotypes. Non-enveloped double-stranded DNA virus (55 nm in diameter)

Answer 207

Verruca vulgaris (common wart)- usually HPV types 1, 2, or 4. Most commonly located on fingers, hands, elbows, and knees. Hyperkeratotic papillomas with punctuate black dots (seed warts) that represent thrombosed capillaries. Verruca plantaris/palmaris (plantar or palmar warts) is usually HPV types 2, 27, and 57. Verruca plana (flat warts) is usually HPV types 3 or 10. Epidermodysplasia verruciformis is usually HPV types 5 and 8

Answer 208

is based on clinical presentation. Biopsy can show benign papilloma with hyperkeratosis and koilocytosis. DNA/RNA in-situ hybridization test commercially available for high-risk genital HPV infections

Answer 209

Locally destructive therapies include Cryotherapy (liquid nitrogen), Electrosurgery, Curettage, and Laser ablation, Podophyllin or podophyllotoxin (blistering agents), and Salicyclic acid preparations. Immunomodifiers includes Interferon- topical, intralesional, systemic (rarely used), Imiquimod (Aldara) and Intralesional candida antigen. Antiviral agents includes Cidofovir (rarely used).

Answer 210

HSV-1 is over 90% prevalence by two years of age in some parts of the world B. With HSV-2, prevalence of antibodies to HSV-2 occur later in life (Less than 1% for college freshmen, Approximately 20% for middle and higher socioeconomic adults, and Prostitutes- 80%). Infections acquired through small breaks in the skin or mucosal membranes (transmitted in saliva, vaginal secretions, vesicle fluid, and direct skin contact)

Answer 211

Two types including HSV-1- primarily lips and HSV-2- primarily genitalia. Large enveloped virus containing double-stranded DNA- icosadeltahedral capsid containing 162 capsomeres. Encodes for two enzymes (thymidine kinase, DNA polymerase) that are excellent targets for antiviral drugs

Answer 212

Primary lesion are grouped vesicles on an erythematous base. Latent period followed by recurrent infections are common. Clinical syndromes includes Herpes labialis (cold sores), Herpetic gingivostomatitis (toddlers and children), Herpetic whitlow, Eczema herpeticum, Neonatal simplex, and Herpes progenitalis

Answer 213

base on clinical presentation. Cytopathicchanges include intraepidermal vesicle with multinucleated keratinocytes and large vesicular nuclei in keratinocytes (balloon cells) These changes can be seen with biopsy and tzanck smear, which is prepared by scraping of a vesicle base and using stains that demonstrate nuclear morphology (e.g., Wright stain). Immunoperoxidase stain of biopsies. Viral culture is usually negative when lesions are crusted (about 5 days). HSV type can be identified with specific DNA probes and antibodies. Serologic procedures are useful only for diagnosing primary HSV infection or for epidemiologic studies.

Answer 214

Topical therapies (in general less effective than oral therapies) include penciclovir 1% cream and cidofovir 1% cream (acyclovir-resistant HSV in immunocompromised patients). Systemic therapies include acyclovir, famciclovir, valacyclovir, and foscarnet (acyclovir-resistant HSV in immunocompromised patients).

Answer 215

More than 90% of adults in developed countries have VZV antibodies. Primarily spread by respiratory route, less commonly by direct contact with the skin vesicles. Highly communicable with rates of infection exceeding 90% among susceptible household contacts

Answer 216

belongs to herpesvirus groups virus. Smallest genome of the human herpes viruses with 124,900 base pairs

Answer 217

includes chickenpox and herpes zoster. Chickenpox (primary infection) has an incubation period of approximately 14 days, fever. Rash is initially erythematous maculopapular lesions- then thin-walled vesicles (2-4 mm) on erythematous base (dew drop on rose petal). New crops of lesions continue to develop for 3-5 days. Herpes zoster (recurrence of the latent varicella zoster infection) is reactivation of VZV that has been dormant in dorsal root ganglion. Virus replicates and travels down sensory nerve to skin produces grouped vesicles on an erythematous base in a distribution that corresponds to one of the sensory nerves. Post-herpetic neuralgia (pain) persists in up 10-15% of elderly patients

Answer 218

bases on clinical presentation. Cytopathicchanges show intraepidermal vesicle with multinucleated keratinocytes and large vesicular nuclei in keratinocytes (balloon cells) these can be see with biopsy or tzanck smear. Viral culture is difficult and rarely done because the virus is labile and replicates poorly in culture. Direct immunofluorescence of skin lesions. PCR studies. Serologic procedures can be used to screen for immunity or document active VZV infection

Answer 219

Chicken pox is mostly based on prevention. VZV vaccine is 70-90% effective in preventing disease. VZV immunoglobulin is passive VZV prophylaxis for immunocompromised individuals, pregnant women, neonates. Oral acyclovir for adults and children. Intravenous acyclovir for immunocompromised patients Herpes zoster (within first 72 hours) can be treated with acyclovir, famciclovir, and valacyclovir.

Answer 220

Most common superficial bacterial infection of children. Usually acquired by direct person-two-person contact. Less commonly acquired through fomites. Predisposing factors include high humidity cutaneous carriage, poor hygiene

Answer 221

β-hemolytic streptococci (Streptococcus pyogenes) can cause non-bullous impetigo of children. Staphylococcus aureus is associated with both non-bullous and bullous impetigo (most common cause of both types of impetigo)

Answer 222

impetigo contagiosa is often applied to streptococcal infections (70 to 80% of all impetigo). Most commonly affects the face followed by the extremities. Typically begins as a single lesion- autoinoculation frequently produces multiple adjacent lesions. Early primary lesion is erythematous macule with superficial blister (rarely appreciated). Developed lesion is “Honey-colored” yellow crust. Mild lymphadenopathy variably present. Up to 5% of streptococcal impetigo case are associated with acute poststreptococcal glomerulonephritis (serotypes 1, 4, 12, 25, 49)

Answer 223

(20 to 30% of all impetigo). May affect any area the body. Typically begins as a single lesion that is autoinoculation frequently produces multiple adjacent lesions. Primary lesion is superficial, flaccid blister that may in occasionally demonstrate layered pus. Older lesions demonstrate collapsed blisters that are often described as having a varnish-like appearance. Staphylococcal scalded skin syndrome- primarily seen in children less than six years of age- produced by phage group II strains that produce exfoliative toxins (ET-A, ET-B) that produce diffuse superficial blisters over large areas of the body

Answer 224

based on clinical presentation. Culture and sensitivity of crust or fluid from intact bullae. Gram stain of crust or fluid from intact bullae (characteristic short chains of gram-positive cocci typical of S. pyogenes amongst numerous neutrophils). Skin biopsy (rarely done)

Answer 225

Local care includes soaking and gentle removal of crusts. Topical antibiotics (limited cases) can be used such as topical mupirocin 2% ointment. Systemic antibiotics (the risk of poststreptococcal glomerulonephritis is not altered by treatment), including Cephalexin, Dicloxacillin, Azithromycin (relatively expensive), and Clarithromycin.

Answer 226

More common in the very young, elderly patients, immunocompromised patients, intravenous drug users, and in patients with chronic ulcers. May also occur is a post-surgical complication. Increased incidence during summer months. Infections occur through breaks in the skin- breaks can be microscopic and not clinically noticeable

Answer 227

(clinical variant of cellulitis) is most commonly associated with β- hemolytic streptococci (Streptococcus pyogenes)

Answer 228

most commonly associated β-hemolytic streptococci (Streptococcus pyogenes), Staphylococcus aureus, and Haemophilus influenzae (in children). Less common species include other groups of streptococci, Pneumococcus species, Klebsiella species, Yersinia species, or even mixed gram-negative and gram-negative infections

Answer 229

an acute infection typically with a skin rash, usually on any of the legs and toes, face, arms and fingers. Most commonly confined to the face less commonly the extremities. Incubation period is 2 to 5 days. Variable systemic symptoms includes fever, chills, and malaise. Primary lesion is sharply demarcated area of erythema (cliff-drop border) that demonstrates non-pitting edema (lesions are often painful). Regional lymphadenopathy is strictly present. Rarely the overlying epidermis may demonstrate bullae, pustules or hemorrhagic necrosis

Answer 230

Most commonly located on the extremities. Incubation period is 2 to 5 days. Primary lesion is ill-defined non-palpable or subtly palpable area of painful erythema fact is warm to the touch. Older lesions may demonstrate variable hemorrhage. Lymphatic streaking commonly present. Regional lymphadenopathy frequently present. Patients may progress to septicemia

Answer 231

is based on clinical presentation. CBC may demonstrate leukocytosis. Biopsy may be consistent with the diagnosis of cellulitis (presence of tissue edema and neutrophils) although organisms are only rarely identified. Tissue culture of biopsy specimens are more sensitive and specific. Culture and gram stain of aspiration from leading-edge occasionally used although rarely successful. Blood cultures may be positive in up to 10% of cases

Answer 232

Treatment is typically corrected against streptococcal or staphylococcal organisms. Mild cases can be treated with Oral cephalexin, Oral dicloxacillin, Oral clarithromycin, Oral azithromycin, and Oral fluoroquinolone antibiotic. Severe cases can be treated with intravenous antibiotics with broad-spectrum coverage (e.g., cases (require hospitalization) piperacillin/ tazobactam or metronidazole plus ciprofloxacin).

Answer 233

Worldwide distribution. In the United States, there are 6693 cases of primary and secondary syphilis confirmed by the CDC in 2003. Sexually transmitted disease and may also be transmitted congenitally or by blood transfusion. Risk of disease from single sexual contact- approximately 30%

Answer 234

Treponema pallidum is a spirochete belonging to the order Spirochaetales. Thin, coiled spirochete measuring 5-15 by 0.1 μ with characteristic motility observable by dark field microscopy

Answer 235

Primary lesion develops at site of inoculation two to six weeks after intercourse. Initially papule that breaks down to produce a characteristically oval ulcer that is indurated (Hunterian chancre) is frequently non-tender. Regional lymphadenopathy is frequently present. Untreated ulcers heal in three to four weeks.

Answer 236

Result hematogenous in lymphatic spread of spirochetes. Typically occurs 4 to 10 weeks after primary syphilis. Lymphadenopathy present in approximately 90% of cases. Types of secondary skin lesions include non-pruritic papulosquamous lesions with varying degrees of scale that vary from red to read-brown to violaceous in color, condylomata lata, nonscarring “moth-eaten” alopecia, split papules at oral commissures, annular lesions on face (nickel and dime lesions), and oral erosions (may resemble snail tracks)

Answer 237

based on clinical presentation. Darkfield examination of exit date from primary or secondary skin lesions, which requires an experienced observer. Skin biopsy is use for identification of spirochetes by Warthin-Starry or modified Steiner stain. Serology tests include nontreponemal tests (VDRL, RPR) and treponemal tests (FTA-ABS, MHA-TP).

Answer 238

Primary and secondary syphilis (and early latent syphilis of less than one year’s duration) requires 2.4 million units of benzathine penicillin as a single intramuscular dose. In penicillin allergic patients- desensitization to penicillin or oral azithromycin. In latent syphilis of greater than one year’s duration or in tertiary syphilis (if neurosyphilis has been excluded)- 2.4 million units of benzathine penicillin given as three intramuscular doses over three weeks. Congenital syphilis and syphilis with coexisting HIV infection require special dosing

Answer 239

Worldwide distribution, some species are geographically restricted. Superficial fungal infections are very common in account for almost 5 million outpatient visits per year (0.7% of all outpatient visits). Infections acquired from humans, animals, fomites (e.g., hats) and soil

Answer 240

At least 30 species of the dermatophytes have been documented produce infections in humans. Dermatophyte food source is keratin (top layer skin, hair, nails). Most common species include Trichophyton rubrum (most common cutaneous pathogen), Trichophyton mentagrophytes (common cause of tinea pedis), Trichophyton tonsurans (common cause of tinea capitis), Microsporum canis (common cause of fluorescent tinea capitis), and Epidermophyton floccosum (common cause of tinea cruris)

Answer 241

infection of scalp hair. Kerion is a variant characterized by abscess formation

Answer 242

infection of the face. Tinea barbae is an infection limited to the beard

Answer 243

infection of glabrous (non-hair bearing) skin. Majocchi's granuloma is a variant characterized by follicular pustules and granulomas

Answer 244

an infection of the genital region

Answer 245

an infection of the hand

Answer 246

infections of the feet

Answer 247

infection of the nail

Answer 248

Base on clinical presentation. Potassium hydroxide (KOH) examination of skin scrapings, hair, or nails organisms appear as hyphae or as arthrospores. Culture is usually on Dermatophyte Test Medium (DTM) or Sabouraud agar. Biopsy with special stains such as PAS with diastase or Gomori methenamine silver (GMS stain)

Answer 249

Topical antifungal agents slicks (usually not used on hair or nail infections) includes Imidazoles (clotrimazole, miconazole, econazole, ketoconazole, oxiconazole, sulconazole), Allylamines (naftifine, terbinafine), and Hydroxypyridones (ciclopirox olamin). Systemic antifungal agents includes Griseofulvin (use limited to tinea capitis), Fluconazole, Itraconazole, and Terbinafine (treatment of choice for tinea unquium).

Answer 250

More commonly effects mucous membranes and skin. Both mucous membrane and skin infections are more common in patients with diabetes, occlusion, use of corticosteroids, or in patients treated with broad- spectrum antibiotics. Candida species are found as normal microflora in the gastrointestinal tract of greater than 80% of individuals

Answer 251

Preferred food source is glucose or serum. Most common pathogenic species are Candida albicans and Less common species include C. tropicalis, C. kefyr, C. glabrata, C. parapsilosis

Answer 252

Oral candidiasis (thrush), Angular cheilitis (perlèche), Cutaneous candidiasis (Diaper dermatitis and Erosio interdigitalis blastomycetica chronica, a variant occurs between the digital spaces of the fingers), Vulvovaginitis, Balanitis, and Chronic mucocutaneous candidiasis- rare severe variant characterized by absence of normal immunity).

Answer 253

base on clinical presentation. With potassium hydroxide (KOH) examination of skin or mucosa scrapings, organisms appear as pseudohyphae or yeast. Culture is usually on Sabouraud agar. Biopsy with special  stains such as PAS with diastase or Gomori methenamine silver.

Answer 254

Topical antifungal agents slicks (usually not used on hair or nail infections) included Imidazoles (clotrimazole troches for oral disease and topical clotrimazole, miconazole, econazole, ketoconazole, oxiconazole, sulconazole for cutaneous disease), Allylamines (naftifine, terbinafine is cutaneous only), Hydroxypyridones (ciclopirox olamine is cutaneous only), Nystatin, and Gentian violet. Systemic antifungal agents include Fluconazole (systemic treatment of choice for mucosal disease), Itraconazole, and Terbinafine (treatment of choice for tinea unquium).

Answer 255

Worldwide distribution. More common in humid and warm climates. Confined to post pubertal patients

Answer 256

Food source is follicular lipids. Malassezia furfur (Pityrosporum orbiculare)

Answer 257

Distribution is primarily truncal. Primary lesion are asymptomatic, fawn (tan)-colored, subtly scaly macules that may develop into large patches. Clinical variant may be hypopigmented due to production azelaic acid that inhibits function of tyrosinase produced by melanocytes. Pityrosporum folliculitis is a clinical variant characterized by follicular papules in pustules on the trunk, arms, and occasionally the face

Answer 258

based on clinical presentation. Potassiumhydroxide (KOH) examination of tape stripped skin or skin scrapings demonstrates characteristic spaghetti (short hyphae) and meatballs (yeast) appearance preparations can also be stained to enhance visualization. Culture requires special lipid-enriched media and is rarely performed

Answer 259

Selenium sulfide shampoo applied topically. Topical imidazoles. Oral therapies including itraconazole and ketoconazole.

Answer 260

Worldwide distribution that affects all ages races and so should economic groups. Higher prevalence in children and people who are sexually active. Mites are spread primarily by person-two-person contact, rarely by fomites

Answer 261

Sarcoptes scabiei variety hominis- highly host specific mite confined to humans. Approximately a 30 day lifecycle in the epidermis before the female lays 60 to 90 eggs that mature in approximately 10 days. Mites are barely visible with naked high- 0.35 x 0.3 mm. Number of mites is highly variable but typically less than 100

Answer 262

symmetric with characteristic areas of involvement being the interdigital webspace of the hands, flexural portion of the wrist, waist, around the axillary areas, genitalia and buttocks. Typically spares the head, palms, and soles

Answer 263

that is accentuated at night or by hot baths and showers

Answer 264

Erythematous papules. Wavy, thread-like grayish-white to slightly erythematous burrows in pathognomonic finding. Distinctive erythematous nodules on male genitalia

Answer 265

excoriations and secondary infections

Answer 266

extensive infestations associated with massive hyperkeratosis- typically seen in immunocompromised individuals and patients with diminished sensory function

Answer 267

based on clinical presentation and identification of characteristic burrows or genital nodules. Mineral oil preparation- a small drop of mineral oil is placed on the skin in gently scraped and examined under a microscope for evidence of infestation (mites, eggs, or feces). Skin biopsy is occasionally needed and can be diagnostic if the mites, eggs or feces (also called scybala) are identified in the epidermis

Answer 268

Permethrin 5% cream is the treatment of choice in most cases (tolerance but not true resistance has been seen in some strains). Lindane 1% lotion has limited use by increasing resistance of mites. Crotamiton 10% has poor efficacy, rarely used. Sulfur 5-10% ointment is messy, smells bad, but is sometimes used in pregnant women. Ivermectin (252 400 μg per kilogram) is a probable treatment of choice in extensive cases or cases that fail topical treatment

Answer 269

Worldwide infestation. Head lice-12 million new cases per year in United States. Crab lice has the highest prevalence in homosexuals and young men between 15 and 40 years of age

Answer 270

a type of lice, bloodsucking, wingless insect that preferentially infest the scalp

Answer 271

a type of lice, preferentially infests the trunk

Answer 272

a type of lice, preferentially affects the hair of the genital area

Answer 273

Limited to scalp with the area behind the ears in the nape of the neck being the area most commonly affected. Symptoms are intense pruritus. Erythema, scale, and secondary infection commonly present. Nits are tan-brown oval eggs attached to hair shafts (relatively easy to find)- once the eggs hatch they are white in color. Lice demonstrate a brown-tan color with six legs and are more difficult to find

Answer 274

Lice and eggs are morphologically identical to head lice but are only found on clothes except during feeding. Clinical findings include intense pruritus and erythematous papules and macules that are most commonly located on the trunk

Answer 275

Limited to hair of genital area and less commonly the eyelashes, beard, or axillary areas. Symptoms-marked pruritus of the genital areas. Nits are similar to those of head lice, the adult louse is usually easily found attached to the base of hairs

Answer 276

based on clinical presentation. Demonstration of either the nit or louse

Answer 277

Pyrethrin (OTC), Permethrin 1% cream rinse (OTC). Lindane 1% shampoo. Malathion 0.5%- most efficacious. Ivermectin (250 μg per kilogram), which has very good efficacy

Answer 278

Disinfestation of clothing and bedding by it fumigation, heating to 65°C for 30 minutes with hot ironing of seams. Topical treatments that are effective against scabies are also often used

Answer 279

Permethrin, Pyrethrin, Lindane 1% shampoo, and Ivermectin

dermatology1.1 Flashcards

(303 cards)