Exam 3 chronic skin infections

Question 1

Describe clinical features of psoriasis

Answer 1

sharply demarcated erythema usually with thick micaceous scale, auspitz sign, koebner phenomenon

Question 2

Describe the histopathology of psoriasis

Answer 2

Extensive hyperkeratosis and parakeratosis, uniform elongation of the rate ridges, neutrophils swarm to epidermis

Question 3

Pathogenesis of psoriasis

Answer 3

T cell mediated autoimmune disorder: T cells produce cytokines that stimulate keratinocyte proliferation

Question 4

What other things can psoriasis be confused with, how do you differentiate?

Answer 4

Lichen simplex chronicus, nummular eczema, seborrheic dermatitis, tinea corporis; punch biopsy

Question 5

Common areas of psoriasis

Answer 5

elbows, knees, presacral, nails, palms and soles

Question 6

What are the 4 different kinds of psoriasis?

Answer 6

Chronic plaque, inverse (fold areas, only erythema), guttate (after strep, tear drop shaped scaled spots), pustular (small pustules becoming generalized with fever)

Question 7

Treatment of psoriasis

Answer 7

topical agents (steroids, retinoids), Systemic (retinoids, cyclosporin, UVB/narrow band, methotrexate)

Question 8

What is the main complication of psoriasis

Answer 8

psoriatic arthritis

Question 9

Describe the hallmarks of lichen planus

Answer 9

6 P’s: planar, purple, polygonal, pruritic, papules, plaques

Question 10

How do you diagnose lichen planus?

Answer 10

punch biopsy

Question 11

What is lichen planus often associated with?

Answer 11

Hepatitis C

Question 12

What is the classical form of lichen planus? Describe

Answer 12

Linear lichen planus; erythematous to violaceous polygonal papules in the flexor ares (wrist and ankles), Wickham’s striae (white patter in mouth)

Question 13

Describe the forms of lichen planus

Answer 13

Hypertrophic: very thick plaques over lichen planus.
Bullous: blisters that occur under lichen planus (interface dermatitis)
Scalp: lichen planopilaris-scarring alopecia of scalp

Question 14

What is the treatment of lichen planus

Answer 14

may resolve spontaneously in 1-2 years, topical steroids, oral steroids, phototherapy STOP THE DRUG IF IT INDUCED IT

Question 15

What kinds of drugs can induce lichen planus?

Answer 15

thiazide, sulfa related, beta blockers, captopril

Question 16

What is the classic sign of acute lupus erythematosus

Answer 16

butterfly rash across the nose and the cheeks, photosensitive pattern of erythema, joint pain as well

Question 17

What are the three types of lupus erythematosus

Answer 17

Acute (pauci-inflammatory interface dermatitis), Subacute (prominent suprabasilar exocytosis of lymphocytes), Discoid (very thick basement membrane)

Question 18

What is the most important lab test for lupus erythematosus? Others?

Answer 18

anti-nuclear antibodies; complete blood count, sed rate, liver/kidney tests, UA

Question 19

What are the risk factors of SLE?

Answer 19

women>men, ages 14-40, more common in african-americans, hispanics, asians

Question 20

Treatment of SLE?

Answer 20

NSAIDs, antimalarials, corticosteroids, immunosuppresants (cyclophosphamide, azathaprine)

Question 21

What triggers SLE

Answer 21

Sunlight, medications (anti-seizure, antibiotics, BP rx)

Question 22

What are some non-specific skin lesions associated with lupus?

Answer 22

Talangiectasia vasculitis, thrombophlebitis, Reynaud’s; Alopecia, urticaria, mucous membrane, pigment changes