Psoriasis

Question 1

epi of psoriasis

Answer 1

2% of world

bimodal pattern (childhood, adulthood)

northern european descent

mild, moderate, severe based on % of body affected

Question 2

psoriatic plaque morphology

Answer 2

well-demarcated circular, oval, or polycyclic erythematous plauqes that are symmetric in distribution

very thick (micaceous) and silvery scales

Question 3

distribution of psoriasis

Answer 3

scalp, elbows and knees

lesions can last from months to years in the same location

Question 4

what is auspitz sign?

Answer 4

removal of scale result in pinpoint bleeding, suggesting dianosis

scraping will raise bright white or silvery scales

Question 5

what is this a presentation of?

Answer 5

Koebner phenomena

trauma-induced psoriasis

can interpret as slow healing wounds

Question 6

what dermatitis co-exist with psoriasis

Answer 6

seborrheic dermatitis

Question 7

psoriatic nail changes can be seen in absence of cutaneous involvement

Answer 7

T

Question 8

what changes are seen in psoriatic nail disease

Answer 8

nail pitting

onycholysis (lifting of distal nail plate)

splinter hemorrhages

subungual hyperkeratosis

leukonychia

oil drop changes (red-brown discoloration)

Question 9

what is inverse pattern of psoriasis

Answer 9

intertriginous areas of body

(axillae, groin, genitals, submammary area)

erythematous and well-demarcated but lack classic scale

Question 10

how is scalp psoriasis treated

Answer 10

topical descaling agents such as salicylic acid or corticosteroids

Question 11

what is this a presentation of?

Answer 11

pustular psoriasis

widespread erythematous, sterile pustules

palmar and plantar involvement

Question 12

increased risk for psoriasis patients

Answer 12

CV disease (MI, PE, cerbrovascular accidents)

screen for diabetes, cholesterol, hypertension, obesity, smoking

chronic renal disease

Question 13

Tx for psoriasis

Answer 13

IV light therapy

<10% BSA involvement: topical (retinoid, corticosteroid, vit D analog, topical tar, anthralin)

>10% BSA: systemic (methotrexate, mycophenolate mofetil, cyclosporine, tacrolimus, acitretin)

Question 14

what is this a presentation of?

Answer 14

pityriasis rosea

Question 15

describe pityriasis

Answer 15

discrete oval, erythematous, scaly plauqes and patches oriented along skin cleavage lines

most commonly on trunk and upper extremities

face palms, soles are usually spared

Question 16

what is this a presentation of?

Answer 16

herald patch

solitary, scaly, pink or flesh-colored plaque

Question 17

speculated etiology of pityriasis rosea

Answer 17

associated with systemic reactivation of human herpes virus 6 and 7

Question 18

what pattern does pityriasis rosea present in?

Answer 18

begin with herald patch (truncal), with fine collarette of scale, patches and plaques form along skin fold lines on trunk

Question 19

what is this a presentation of?

Answer 19

lichen planus

Question 20

describe the pathophysiology of lichen planus

Answer 20

autoreactive T lymphocytes attack basal kertinocytes in skin, mucous membranes, hair follicles, and/or nail units

unclear etiology

Question 21

presentation of lichen planus

Answer 21

pruritic, flat-topped, pink to purple papules that are localized most commonly along the volar wrists, shins, presacral area, and hands

Question 22

what has been associated with cause of lichen planus?

Answer 22

hep b vaccination

medications causing lichen planus-like eruption

Question 23

what phenomenon is a hallmark of lichen planus (same for psoriasis)

Answer 23

Koebner phenomenin

Question 24

what is this a presentation of?

Answer 24

lichen planus

Question 25

describe mucous membrane involvement of lichen planus

Answer 25

lacy, net-like, white plaques with violaceous base on tongue or buccal mucosa

Question 26

Tx of lichen planus

Answer 26

withdraw potential offending medication

antihistamines for pruritus

systemic corticosteroids

metronidazole

systemic retinoids

phototherapy

Question 27

what is this a presentation of?

Answer 27

pityriasis rubra pilaris (PRP)

acute cutaneous eription accompanied by pruritus and/or pain

follicular papules on erythematous base coalescing to form large orange-red plauqes but islands of sparing

commonly begin on scalp, rapidly spread in craniocaudal direction

Question 28

what is this a presentation of?

Answer 28

erythroderma

diffuse redness of skin >90% of body surface

Question 29

causes of erythroderma

Answer 29

psoriasis, atopic dermatitis, idiopathic erythroderma, cutaneous T-cell lymphoma, drugs

Question 30

what can induce erythroderma?

Answer 30

drugs such as allopurinol, ampicillin, omeprazole, vancomycin