Pityriasis Rosea Flashcards
characteristic
Mild inflammatory exanthem characterized by salmon colored thin papules and plaques that are first discreet but may become confluent the individual patches are oval or circinate and covered with finally crinkled dry epidermis which often desquamates leaving a collarette of scaling
When stretched across the long axis the scales tend to fold across the stretch of lines and it is so called as
Hanging curtain sign
Christmas tree sign
The total course last how many weeks
3- 8 weeks
It begins as what lesion
Begins as a single herald or mother patch. larger than succeeding lesions. persist for 1 week or longer before others appear.
Age of highest incidence
15-40 yo
spring and autumn
Women
Areas of predilection
Generalized
Trunk
sparing sun exposed areas
PR occurring during pregnancy may be associated with
premature delivery
neonatal hypotonia
fetal loss
spec if eruption occurs within first 15 weeks gestation.
iMost likely response to what virus
HHV 6/7
Histo
Mild acanthosis
focal parakeratosis
extravasation of erythrocytes into epidermis
spongiosis- acute areas
mild perivasc infiltrate of lymphocytes.
PR- APESL
tx
most pxs have no tx because they are asymptomatic.
Acyclovir- dec in eruption.
erythromycin- but GI side effects of ery may limit use.
nbUVB- help improve individual lesions.
corticosteroid cream and lotions- relief form itching
