Rheumatology and Dermatology Flashcards
(51 cards)
1
Q
Nonepithelial/Nonjunctional Adhesion Mechanisms
A
- Cadherins
- ICAMs
- Integrins
- Selectins
2
Q
Hemidesmosome, cadherin, integrin, ICAM-l. Which joins only cells of the same type and does not attach cells to the basement membrane?
A
Cadherins
3
Q
Fibroblasts are involved in which tissues?
A
- Stimulated by tissue damage
- Involved in Collagen
- Glycosaminoglycans
- Reticular and elastic fibers
- Glycoproteins
4
Q
Melanocytes
A
- Melanin-producing cells
- Located in the stratum basale (bottom layer) of the epidermis
- Responsible for skin color
5
Q
Energy Exchange That Takes Place at the Skin
A
- UV light is used to generate vitamin D
- Melanocytes displace UV light as heat
- Bilirubin is converted
- Dendritic cells process antigens
- Mechanical energy is converted to electrical energy by nerve endings
6
Q
Macule
A
Flat discoloration < 1cm (ie Tinea versicolor)
7
Q
Patch
A
Macule (flat discoloration) > 1cm
8
Q
Papule
A
- Elevated skin lesion < 1 cm
- example: Acne vulgaris
9
Q
Plaque
A
- Papule> 1 cm
- example: Psoriasis
10
Q
Vesicle
A
- Small fluid-containing blister
- example: Chickenpox
11
Q
Wheal
A
- Transient vesicle
- example: Hives
12
Q
Bulla
A
- Large fluid-containing blister
- Example: Bullous pemphigoid
13
Q
Keloid
A
- Irregular, raised lesion resulting from scar tissue
- example: T pertenue (yaws)
- Follows trauma to skin, especially in African-Americans
- Usually upper chest
14
Q
Pustule
A
Blister containing pus
15
Q
Crust
A
- Dried exudates from a vesicle, bulla, or pustule
- Example: Impetigo
16
Q
Hyperkeratosis
A
- ↑ thickness of stratum corneum
- Psoriasis
17
Q
Parakeratosis
A
- Hyperkeratosis with retention of nuclei in stratum corneum
- Psoriasis
18
Q
Acantholysis
A
- Separation of epidermal cells
- Pemphigus vulgaris
19
Q
**Acanthosis **
A
Epidermal hyperplasia (↑ spinosum)
20
Q
Dermatitis
A
Inflammation of the skin
21
Q
Verrucae
A
- Warts
- Soft, tan-colored, cauliflower-like lesions.
- Epidermal hyperplasia, hyperkeratosis,koilocytosis.
- Verruca vulgaris on hands;
- Condyloma acuminatum on genitals (caused by HPV 6 and 11)
22
Q
Nevocellular nevus
A
- Common mole
- Benign
23
Q
Urticaria
A
- Intensely pruritic wheals that form after mast cell degranulation
24
Q
Ephelis
A
- Freckle
- Normal number of melanocytes
- ↑melanin pigment
25
Atopic dermatitis (eczema)
* **Pruritic eruption, commonly on skin flexures**
* Often associated with other atopic diseases (asthma, allergic rhinitis)
26
Allergic contact dermatitis
* **Type IV hypersensitivity reaction that follows exposure to allergen**
* Lesions occur at site of contact
27
Atopic dermatitis (eczema) Treatment
* **Switching to a moisturizing soap** (Dove, Aveeno) and adding an OTC emollient may be all that is needed for maintenance and mild cases;
* **Calcineurin inhibitors**: tacrolimus (Protopic) or pimecrolimus (Elidel);
* **Topical Steroids**
* **Antibiotics for open lesions** (cover Staph. aureus and Strep. spp.);
* **Antihistamines**
* **Leukotriene inhibitors** (Montelukast) — theoretical efficacy supported by weak studies;
* **UV light therapy**
* **Systemic steroids** (1-2mg/kg/d in children then taper) only in severe cases and only for short duration;
* **For very severe cases**, consider **methotrexate, cyclosporin, azathioprine**
28
Psoriasis
* **Papules aiid plaques with silvery scaling, especially on knees and elbows**
* **Acanthosis** with **parakeratotic** scaling (nuclei still in stratum corneum)
* **↑ stratum spinosum, ↓stratum granulosum**
* **Auspitz sign** (bleeding spots when scales are scraped off)
* Can be associated with nail pitting and psoriatic arthritis
29
Acne Pathophysiology and Treatment
* **Hyperkeratosis** - Isotretinoin (Vitamin A derivatives)
* **Sebum overproduction** - Estrogen, Spirinolactone
* ***Propionibacterium acnes*** proliferation - Topical - Benzoyl Peroxide, Antibiotics - Erythromycin, tetracycline, doxycycline, clyndamycin
* **Inflammation** - Inject with steroids
30
A pregnant patient comes to the clinic complaining of new dark pigmentation on her face. What is the most likely diagnosis?
Melasma
31
What are some of the hallmark features of necrotizing fasciitis? What organism causes this infection?
* Rapidly spreading cellulitis
* Tenderness beyond red border
* Strep pyogenes (GAS)
32
What organism causes painless white patches on the tongue that cannot be scraped off?
**EBV -** oral hairy leukoplakia
33
What is a lesion of excessive collagen deposition especially around the face ears, neck or upper chest called?
Keloid
34
What organism is responsible for acne vulgaris?
*Propionibacterium acnes*
35
Seborrheic keratosis
* **Flat, greasy, pigmented squamous epithelial proliferation with keratin-filled cysts (horn cysts) **
* Looks “pasted on”
* Lesions occur on head, trunk, and extremities
* **Common benign neoplasm** of older persons
* **Sign of Leser-Tréla**t - sudden appearance of multiple seborrheic keratoses indicating an underlying malignancy (e.g., CI, lymphoid).
* Melanoma part of DDx
36
Impetigo
* Very superficial skin infection
* Usually from *S. aureus or S. pyogenes*
* Highly contagious
* **Honey-colored crusting**
37
Cellulitis
* Acute, painful spreading infection of dermis and subcutaneous tissues.
* Usually from S. pyogenes or S. aureus.
38
Necrotizing fasciitis
* Deeper tissue injury, usually from anaerobic bacteria and S. pyogenes
* Results in crepitus from methane and CO2 production
* “Flesh- eating bacteria”
39
**Staphylococcal scaled skin syndrome (SSSS)**
* **Exotoxin destroys** keratinocyte attachments in the **stratum granulosum only**
* Characterized by **fever and generalized erythematous rash** with **sloughing of the upper layers of the epidermis.**
* Seen innewborns and children
40
Hairy leukoplakia
* White, painless plaques on the tongue that cannot be scraped off.
* EBV mediated.
* Occurs in HIV positive patients.
41
Blistering skin disordes
* **Pemphigus vulgaris** - IgG against desomosomes, Acantholysis - intraepidermal bullae causing flaccid blister involving skin and oral mucosa, Positive Nikolsky
* **Bullous pemphiogoid** - Autoimmune disorder IgG against hemidesomsomes, antibodies are "bullow" the epiidermis, Spares oral mucosa, Negative Nikolsky
* **Dermatitis herpetiformis** - pruritic papules and vesicles deposits of IgA at tip of dermal papillae - celiac disease
* **Erythema multiforme** - Infections (M. pneumoniae, HSV), drugs, cancer, autoimmune, macules, papules, vesicles, target lesions
* **Stevens-Johnson syndrome** - Fever, bulla and necrosis, sloughing of skin, Drugs - Seizure meds, sulfa, penicillins, allopurinol.
* **TEN** worse form \>30% skin sloughing/necrosis
42
Lichen Planus
* **Pruritic**
* **Purple**
* **Polygonal**
* **Papules**
* **Sawtooth** infiltrate of lymphocytes at the dermal-epidermal junction
* Treat w/ 5-FU
43
**Actinic keratosis**
* **Premalignant lesions** caused by sun exposure
* Small, rough, erythematous or brownish papules
* **"Cutaneous horn"**
* Risk of carcionoma proportional to epithelial dysplasia
44
Acanthosis nigricans
* Hyperplasia of **stratum spinosum**
* Associated with hyperinsulinemia (Cushing's disease, diabetes)
* Visceral malignancy
45
Erythema nodosum
* Inflammatory lesions of subcutaneous fat
* Usually on anterior shins
* Associated with coccidioidomycosis, histoplasmosis, TB, leprosy, streptococcal infections, **sarcoidosis**
46
Pityriasis rosea
* "Herald patch" (2-10cm oval read patch) Followed days later by "Christmas tree" distribution
* Multiple papular eruptions
* Remits spontaneously
* Strawberry and cherry hemangiomas also possible
47
Most common skin cancers
1. Basal cell carcioma
2. Sqamous cell carcinoma
3. Melanoma
48
Order of metastatic risk in skin cancer
1. Melanoma
2. Squamous cell carcinoma
3. Basal cell carcinoma
49
**Squamous cell carcinoma**
* Very common
* UV sunlight and Arsenic
* Commonly appear on hands and face, **lower lip**
* Rarely metastasize
* **Ulcerative red lesion**
* Associated with chronic draining sinuses
* **Histo: Keratin "pearls"**
* **Actinic keratosis** is precursor to SCC
* **Keratocanthoma** - variant that grows rapidly (4-6 weeks) regresses spontaneously (4-8 weeks)
50
Basal Cell Carcinoma
* Sun exposed areas
* **Upper lip**
* Locally invasive almost never matastasizes
* Rolled edges with central ulceration
* Pearly papules commonly with telangiectasias
* **Histo: peripheral "Palisading" nuclei**
51
Melanoma
* Common tumor with significant risk for metastasis
* **S-100 tumor marker**
* Sunlight exposure - fair skin higher risk
* **_$ Depth correlates with risk of metastasis_**
* **Dysplastic nevus** (atypical mole) is precursor
* **$ ABCDs and Hx of change - **
* ****_A_**symmetry**
* ****_B_**order irregularity**
* ****_C_**olor variation**
* ****_D_**iameter \> 6 mm**
