Flashcards in Dermatology Deck (128):
What is Nikolsky's sign?
easy removal of skin by just little pressure such that the examiner's finger is pulling skin off like a sheet
What three diseases are associated with Nikolsky's sign being present?
1. pemphigus vulgaris
2. staphylococcal scalded skin syndrome
3. toxic epidermal necrolysis
A young pt (30-40s) presents with thin fragile bullae similar to a burn, lesions are painful but not pruritic, involves oral mucosa, destruction is within epidermal layer, Nikolsky's sign presents, and a possibly have a history of ACE inhibitor/ penicillamine use most likely suffers from ...
(antibodies to intracellular spaces of epidermal cells)
What is the most accurate test for pemphigus vulgaris?
What is the treatment for pemphigus vulgaris?
(if steroids uneffecteive use azathioprine/mycophenolate/ cyclophosphamide)
An older pt (70-80s) presents with painful, thick walled bullae in which destruction was in the deep skin layers, no oral lesions or Nikolsky's sign, possible history of using sulfa drugs, and minimal chance of infection or fluid loss most likely suffers from ...
What is the best diagnostic test for bullous pemphigoid?
biopsy with immunofluorescent antibodies
What is the best initial treatment for bullous pemphigoid?
systemic steroids (prednisone)
What are alternative treatments for bullous pemphigoid?
2. erythromycin with nicotinamide
A pt presents with superficial, easily broken bullae, a possible history of ACE inhibitor/ NSAIDs, history of other autoimmune diseases but no oral lesions most likely suffers from ...
What is the diagnostic test and treatment for pemphigus foliaceus?
A pt with a history of alcoholism/ liver disease/ chronic hep C/ oral contraceptive use/ diabetes presents with nonhealing blisters on the sun-exposed parts of the body (face/ back of hands), hyperpigmentation of skin and hypertrichosis (abnormal hair growth) of the face resembling a werewolf most likely suffers from ...
Porphyria Cutanea Tarda
(photosensitivity reaction to accumulated porphyrins due to abnormal porphyrin metabolism)
What is the diagnostic test for porphyria cutanea tarda?
urinary uroporphyrins (elevated 2-5x above the coproporphyrins)
What is the treatment for porphyria cutanea tarda? (5)
1. stop drinking alcohol
2. stop all estrogen use
3. use barrier sun protection (sunscreen, hat, etc)
4. remove iron (phlebotomy or deferoxamine)
5. chloroquine (increases porphyrins excretion)
A pt develops evanescent wheals and hives within 30 minutes of a new medication/ insect bite/ ingestion of food/ emotionally stressful event/ contact with latex, the lesions are pruritic and last less than 24 hours most likely suffers from ...
(hypersensitivity reaction mediated by IgE and mast cells)
What are three signs of chronic urticaria?
1. dermatographism (pressure on skin results in urticaria)
2. cold (induces urticaria)
3. vibration (induces urticaria)
What is the best treatment for acute urticaria?
H1 antihistamines (diphenhydramine/ benadryl, hydroxyzine, cyproheptadine)
What is the next best step in management of acute urticaria that is life threatening?
add systemic steroids to H1 antihistamines
What is the best treatment for chronic urticaria?
nonsedating antihistamines (loratadine, desloratadine, fexofenadine, cetirizine)
What is the best treatment for urticaria when the trigger can not be avoided?
desensitization (stop beta blocker before procedure bc inhibit epinephrine if needed)
A pt develops a generalized maculopapular eruption that blanches with pressure similar to measles after exposure to a medication or even after the medication has been stopped most likely suffers from ...
(typical drug reaction; lymphocyte mediated)
What is the treatment for morbilliform rash?
A pt develops targetlike or irislike lesions on the palms and soles, lesions do not occur on mucous membranes, and pt has a history of penicillin/ phenytoin/ NSAIDs/ sulfa use or infection with herpes simplex/ mycoplasma most likely suffers from ...
What is the treatment for erythema multiforme?
antihistamines and treat underlying infection
A pt presents with severe skin lesions involving less than 10-15% of total body surface area, it involves mucous membranes (oral and conjunctiva), and can involve the respiratory tree (requiring mechanical ventilation), Nikolsky's sign is absent and have a history of penicillin/ sulfa/ NSAIDs/ phenytoin/ phenobarbital use most likely suffer from ..
Stevens Johnson Syndrome
(hypersensitivity response to medications)
What are the medications that can induce Stevens Johnson syndrome and Toxic Epidural Necrolysis? (5)
2. sulfa drug
A pt presents with severe skin lesions involving more than 30% of total body surface area, involves mucous membranes and respiratory tree (requiring mechanical ventilation), NIkolsky's sign is present, full thickness split of skin and have a history of penicillin/ sulfa/ NSAIDs/ phenytoin/ phenobarbital use most likely suffer from ..
Toxic Epidermal Necrolysis
(hypersensitivity reaction to medications)
What is the best diagnostic test for toxic epidermal necrolysis?
A pt develops a round, sharply demarcated lesions that leaves a hyperpigmented spot and the lesion occurs at the precise same anatomic site on the skin with repeated drug exposure most likely suffers from ..
Fixed Drug Reaction
What is the treatment for fixed drug reaction?
A pt presents with painful, red raised nodule on the anterior surface of the lower extremity, nodules are tender to palpation but dont ulcerate, last about 6 weeks and are associated with pregnancy/ streptococcal infection/ coccidioidomycosis/ histoplasmosis/ hepatitis/ sarcoidosis/ inflammatory bowel disease/ syphillis/ enteric infection (Yersinia) most likely suffers from ...
What is the treatment for erythema nodosum?
analgesics, NSAIDs and treating underlying disease
What is the best initial test for fungal infections (tinea pedis, tinea cruris, tinea corporis, tinea veriscolor, tinea capitis, onychomycosis)?
potassium hydroxide (KOH) test of skin
What is the most accurate test for fungal infections (tinea pedis, tinea cruris, tinea corporis, tinea veriscolor, tinea capitis, onychomycosis)?
fungal culture (could take up to 6 weeks; not needed unless infection of hair or nail)
What is the best treatment for fungal infection of hair (tinea capitis) or nails (onychomycosis)? (2)
1. oral terbinafine
2. oral itraconazole
(6 weeks for fingernail, 12 weeks for toenails)
What is a major side effect of terbinafine?
hepatotoxicity (check liver function tests periodically)
What are major side effects of systemic ketoconazole? (2)
What is the best initial treatment for a bacterial skin infection (impetigo, erysipelas, cellulitis, folliculitis, furuncles, carbuncles)?
1. oral dicloxacillin
2. oral cephalexin
3. oral cefadroxil
What are the IV equivalents of dicloxacillin? (2)
1. IV oxacillin
2. IV nafcillin
What is the IV equivalent of cefadroxil?
What is the best initial treatment for a bacterial skin infection (impetigo, erysipelas, cellulitis, folliculitis, furuncles, carbuncles) when the patient is allergic to penicillin and it is only a rash?
What is the best initial treatment for a bacterial skin infection (impetigo, erysipelas, cellulitis, folliculitis, furuncles, carbuncles) when the patient is allergic to penicillin and it is anaphylaxis?
1. macrolides (erythromycin, azithromycin, clarithromycin)
2. flurorquinolones (levofloxacin, gatifloxacin, moxifloxacin)
3. IV vancomycin
(avoid cephalosporins, ciprofloxacin)
What is the best initial treatment for bacterial skin infection (impetigo, erysipelas, cellulitis, folliculitis, furuncles, carbuncles) in a nursing home patient or pt who has been in the hospital for long time?
(treating for possible MRSA; second line is linezolid or Bactrim)
A pt presents with a superficial, weeping, oozing, honey colored and draining skin lesion that occured during warm, humid conditions in a pt who lives in poverty most likely suffers from ....
(can causes glomerulonephritis but not rheumatic fever)
What is the treatment for Impetigo?
topical mupirocin (if not effective, then oral antistaphylococcal antibiotics)
A pt presents with fever, chills, bacteremia, and bright red angry swollen appearing face most likely suffers from ...
(dermis and epidermal Strep pyogenes infection)
What is the treatment for Erysipelas?
systemic oral or IV antibiotics
(if confirmed Strep, then penicillin G)
... is a bacterial infection of the dermis and subcutaneous tissues with Staph and Strep
(tx with IV abx if there is fever, hypotensions, signs of sepsis)
A pt presents with redness, oozing lesion around hair follicles after spending time in a whirlpool or hot tub that is nontender most likely suffers from ....
Folliculitis due to Pseudomonas
What is the treatment for folliculitis?
What is the treatment for furuncles (small collection of infected material around hair follicle) and carbuncles (localized skin abscess around hair follicle)?
systemic antistaphylococcal antibiotics
A pt with a possible history of diabetes presents with a very high fever, bullae lesion with palpable crepitus, pain is out of proportion to the superficial appearance of the skin, and imaging showing air in the tissue or necrosis most likely suffers from..
(life threatening; cellulitis dissects into fascial planes)
What are the two microorgnisms most commonly involved in necrotizing fasciitis?
What is the best treatment for necrotizing fasciitis?
1. surgical debridement with beta lactam/ beta lactamase combo medication (ampicillin/sulbactam, ticarcillin/ clavulanate, piperacillin/tazobactam)
2. surgical debridement with clindamycin and penicillin if known to be group A strep
.... is an infection loculated under the skin surrounding a nail
What is the treatment for paronychia?
small incision for drainage with antistaphylococcal antibiotics
A pt presenting with multiple painful vesicles on their genitalia most likely suffer from ...
What is the best initial test and what is the most accurate test for herpes simplex infection of genitals?
Tzanck smear; viral culture (takes 24-48 hours)
What is the best initial treatment for herpes simplex infection of genitals?
oral acyclovir (famiciclovir or valacyclovir)
What is the best initial treatment for acyclovir-resistant herpes?
What patient should be treated with acyclovir/ valcyclovir/ famiciclovir during an initial chickenpox (herpes zoster) infection? (2)
1. child who is immunocompromised
2. primary infection as adult
What are the common complications of varicella infection? (3)
A pt presents with vesicles that are 2-3 mm in size on an erythematous base like a dew drop most likely suffers from ...
Chickenpox (herpes zoster-varicella infection)
A pt presenting with vesicles on an erythematous base in a dermatomal distribution most likely suffers from ..
Shingles (reactivation of herpes zoster-varicella)
What treatment has the best efficacy for decreasing the risk of postherpatic neuralgia in a Shingles pt?
rapid administration of acyclovir
What Shingles patients should received steroids?
elderly pts with severe pain
What three medications can be used to manage pain in shingles pt?
1. gabapentin (most effective)
3. topical capsaicin
What is the next best step in the management of a nonimmune adult who was exposed to chickenpox?
varicella zoster immunglobulin within 96 hours
A pt presents with heaped up, translucent white or flesh colored lesions on the mucosal surfaces especially of the genitalia most likely suffers from ...
Human Papillomavirus (HPV) Warts
What is the treatment options for human papillomavirus/ condylomata acuminata?
1. mechanical removal (cryotherapy, laser removal, trichloroacetic acid, podophyllin)
2. imiquimod (takes several weeks)
(avoid podophyllin in pregnancy)
A pt presents with an ulceration with heaped up indurated edges that is painless on the genitals most likely suffers from ..
What is the best initial test for primary syphillis?
What is the treatment for primary syphillis?
single intramuscular dose of penicillin
(if allergic, doxycycline orally for 2 weeks)
A pt presents with generalized copper colored maculopapular rash that is particularly intense on palms and soles of feet along with mucous patch, alopecia areata, and condylomata lata most likely suffers from ...
What is the best initial test for secondary syphillis?
What is the treatment for secondary syphilis?
single intramuscular dose of penicillin
(if allergic, doxycycline orally for 2 weeks)
A pt presents with pruritic lesions in the web spaces of the hands and feet and around the penis and breast, and when looked at closely burrows and excoriations around the pruritic vesicles can be seen most likely suffers from ...
An immunocompromised pt/ HIV pt presents with pruritic lesions in the web spaces of the hands and feet and around the penis and breast that severely crust, and when looked at closely burrows and excoriations around the pruritic vesicles can be seen most likely suffers from ...
What is the best diagnostic test for Scabies?
scraping out the organism after mineral oil is applied to burrow
What is the best treatment for Scabies?
(oral ivermectin for norwegian scabies)
A pt presents with pruritic lesions involving the head, easily transmitted by sharing hats and hairbrushes, and a rust colored organism can be detected under magnification at the site most likely suffers from ..
(Lice and Crabs)
What is the best treatment for pediculosis (lice and crabs)?
(can also use over the counter pyrethrins)
What is the best diagnostic test for pediculosis (lice and crabs)?
see organism attached to hair-bearing areas under magnification
A pt presents with a rash that is erythematous with central clearing and is at least 5 cm in diameter after walking through the woods or tall grass, rash possibly appeared about 7-10 days after a tick bite most likely suffers from ...
What is the next best step in management of a pt with a rash that is erythematous with central clearing and at least 5 cm in diameter?
start oral doxycyline, amoxicillin, cefuroxime
(to prevent joint, neuro, and cardiac disease)
A pt with a histor of nasal packing/ retained sutures/ retained surgical material/ prolonged tampon use presents with fever > 102, systolic blood pressure
Toxic Shock Syndrome
(due to staphylococcus attached to foreign body)
What is the treatment for Toxic Shock Syndrome? (3)
1. vigorous fluid resuscitation
2. pressors (dopamine)
3. antistaphylococcal meds (oxacillin, nafcillin, cefazolin; if MRSA then linezolid or vancomycin)
A pt presents with loss of superficial granular layers of the epidermis in sheets, Nikolsky's sign present, normal blood pressure, and no involvement of liver/kidney/ bone marrow/ CNS with an infection most likely suffers from ...
Staphylococcal Scalded Skin Syndrome (SSSS)
What is the initial best step in management of a patient with staphylococcal scalded skin syndrome? (2)
1. admit to burn unit
2. give oxacillin or naficillin
A woolsorter or multiple pts from same location present with a papule that later becomes inflamed and develops central necrosis that is black in color most likely suffers from ...
What is the diagnostic test for anthrax?
gram stain and culture of lesion
What is the treatment for cutaneous anthrax?
Ciprofloxacin or doxycycline
What are the four major characteristics of a benign skin lesion?
1. do not grow in size
2. smooth regular borders
3. diameter is
What is the most accurate test for a skin lesion?
What is the most important prognostic factor for melanoma?
What is the best type of biopsy for suspected melanoma (malignant lesion grows in size, has irregular borders, uneven shape and inconsistent color)?
full thickness biopsy (to asses degree of thickness)
What is the treatment for melanoma?
(interferon can reduce recurrence rates)
An elderly pt presents with a hyperpigmented lesion with a stuck on appearance located on the face/ shoulders/ chest/ back that has benign characteristics most likely suffers from ..
What is the treatment for seborrheic keratosis?
removal with liquid nitrogen (cosmetic purposes)
An elderly light skinned pt presents with skin lesions on sun-exposed areas of the body that can be tender to touch most likely suffers from ..
What is the treatment for actinic keratosis?
1. sunscreen (prevent progression and recurrence)
2. removal (cryotherapy, topical 5-FU, imiquimod, topical retinoic acid, curettage)
An elderly smoker presents with a malignant appearing lesion on sun-exposed skin, especially lip, that ulcerates most likely suffers from ..
Squamous Cell Carcinoma
(rarely metastasize; tx with surgical removal)
A pt presents with a malignant appearing lesion that is shint or pearly in appearance most likely suffers from ..
Basal Cell Carcinoma
What is the best diagnostic test for suspected basal cell carcinoma?
shave or punch biopsy
What is the best treatment for basal cell carcinoma?
Mohs microsurgery (instant frozen sections performed during removal to assess if enough tissue removed)
A HIV pt with CD4 count less than 100 presents with purplish lesions on the skin most likely suffers from ...
(can occur in non HIV pts)
What is the treatment for Kaposi's sarcoma in an HIV pt?
antiretroviral therapy and raising CD4 count
What is the treatment for Kaposi's sarcoma in non-HIV pt?
liposomal adriamycin and vinblastine
A pt presents with silvery scales that develop on extensor surfaces with associated nail pitting and KOebner phenomenon (development of lesions to site of epidermal injury) most likely suffers from ..
(all pts should use salicylic acid to remove heaped up collections of scaling and emollients)
What is the best treatment for localized psoriasis?
(can substitue with topical vitamin D/ calcipotriene or topical vitamin A/ tazarotene)
What is the best treatment for severe psoriasis?
coal tar or anthralin derivatives
(can substitue with topical vitamin D/ calcipotriene or topical vitamin A/ tazarotene)
What is the best treatment for psoriasis that covers more than 30% of total body surface area?
ultraviolet light (most rapid way to control extensive disease)
What is the best treatment for most severe, widespread, progressive psoriasis and its potential side effect?
methotrexate; liver fibrosis
What is the treatment for xerosis/ asteatotic dermatitis?
humidifers and emollients
(use topical steroids if severely inflamed)
A pt presents with red, itchy plaques of the flexor surfaces and high IgE levels most likely suffers from ..
What is the best preventative therapy for atopic dermatitis?
1. moisten skin with emollients
2. avoid hot water
3. avoid drying soaps
4. wear cotton clothes (to avoid skin drying)
What is the treatment options for active atopic dermatitis? (6)
1. topical steroids (topical immunosuppressants like tacrolimus, pimecrolimus)
3. coal tars
5. antistaphylococcal antibiotics (if impetigo present)
6. doxepin (to stop pruritus)
A pt presents with scaly, greasy flaky skin on a red base on the scalp/ around eyebrows/ in nasolabial fold along with "dandruff" on the face most likely suffers from ..
(oversecretion of sebaceous material and hypersensitivity to pityrosporum ovale fungal infection)
What are the treatment options for Seborrheic Dermatitis?
1. low potency steroids (hydrocortisone)
2. topical antifungal (ketoconazole, selenium sulfide)
3. zinc pyrithione shampoo
What is the best preventative therapy for stasis dermatitis (hyperpigmentation built up from hemosiderin in tissue after long venous incompetence of the lower extremities leading to microscopuc extravasation of blood in dermis)?
elevation of legs and lower extremity support hose
A pt presents with linear streaked vesicles after contact with soaps/ detergents/ latex/ sunscreen/ neomycin/ jewelry/ metal nickel/ poison ivy most likely suffers from ..
What is the definitive diagnostic test for contact dermatitis?
What is the treatment for contact dermatitis?
1. identifying causative agent and avoiding it
A pt presents with pruritic eruption that begins as hearld patch and becomes erythematous and salmon colored maculopapular rash that spares the palms and soles, VDRL/RPR is negative and the lesions on the back appear to be in a christmas tree pattern most likley suffers from ...
(self-limited within 8 weeks; use steroids for itching)
What is the best initial treatment for mild acne?
topical antibiotics (clindamycin/ erythromyocin/ sulfacetamide) with benzoyl peroxide
What is secondary treatment for mild acne?
topical steroids (if controlling load of bacteria locally is ineffective)
What is the best initial treatment for moderate acne?
benzoyl peroxide with retinoid (tazarotene, tretinoin, adapalene)