Pityriasis Rubra pilaris

Question 1

Age distribution of PRP:

Answer 1

• Bimodal in first and sixth decades

Question 2

Etiology of PRP:

Answer 2

• unknown

Question 3

Describe the distribution of PRP

Answer 3

classically begins on head/neck and progresses caudally

Question 4

Describe the clinical features of PRP

Answer 4

***picture a guy on the beach wearing sandals, cooking salmon that he caught, grating nutmeg onto it, and wearing big waxy red-orange oven mitts (waxy keratoderma) - starts with scalp erythema w/ fine diffuse scaling - then folliculocentric keratitis papule on erythematous base (nutmeg grater papule) - papules coalesce into orange to salmon-colored plaques with “islands of sparing” on trunk and extremities (this can progress to erythroderma) - Orange-red waxy keratoderma of palms/soles (PRP sandals - Thick yellow brown nails w/ sublungual debris that LACKS PITTING (vs psoriasis)

Question 5

Type I PRP: - AKA _____ form - speed of onset - clinical picture - prognosis - ___ % will resolve within ____ amount of time

Answer 5

• classical adult form - rapid onset - classical clinical findings (guy on beach with sandals and big orange waxy oven mitts, cooking salmon and grating nutmeg on it) - good prognosis -80% clear within 3 years

Question 6

Type II PRP: - AKA ____ form - speed of onset - clinical findings - prognosis

Answer 6

• atypical adult form - slow onset - ichthyosiform leg lesions + Keratoderma w/ coarse and lamellate scale +/- alopecia - chronic course

Question 7

Type III PRP: - AKA ____ form - speed of onset - clinical findings - prognosis

Answer 7

• classical juvenile form - same presentation and course as type I - peaks in adolescence and first two years of life

Question 8

Type IV PRP: - AKA ____ form - clinical findings - prognosis - age of onset

Answer 8

• Circumscribed Juvenile form - follicular papule and erythema on elbows and knees - variable course - prepubertal age of onset

Question 9

Most common form of PRP in children?

Answer 9

• Type IV, circumscribed juvenile form

Question 10

Type V PRP: - AKA ___ form - age of onset - clinical fx - prognosis

Answer 10

• atypical juvenile form - first few years of life - PRP + sclerodermoid changes of hands/feet - chronic course

Question 11

Type VI PRP is a/w _____ and presents in patients with what three findings

Answer 11

• a/w HIV - p/w acne conglobata, HS, follicular spines

Question 12

Histopath of PRP

Answer 12

• alternating orthokeratosis and parakeratosis (checkerboard pattern) - Follicular plugging - shoulder parakeratosis (PK at edges of hair follicles)

Question 13

First line tx of PRP:

Answer 13

• isotretinoin or acitretin - can also use high-dose vitamin A, MTX, TNF-alpha inhibitors, phototherapy

Question 14

Prognosis of types 1-5:

Answer 14

• classical forms (1 and 3) reliably self-resolve in 3-5 year - atypical and circumscribed forms (2,4,5) persist much longer