Pityriasis rosea

Question 1

What is pityriasis rosea?

Answer 1

pityriasis = causes fine flake
rosea = pink coloured

Widespread rash caused by viral infection (possibly herpesvirus type 6 and 7)

• starts with a HERALD patch
• multiple patches of 1-2 weeks and last 6-12 weeks
• affects trunk and upper arms and legs; “Christmas tree” distribution
• commonly in teenagers and young adult but can be any age
• often intensely itchy

Question 2

Presentation of Pityriasis rosea?

Answer 2

• may have prodromal viral symptoms (malaise, nausea, fever, joint pains, headaches)
• itch (can be severe)
• may start with a single herald patch
• main rash comes 1-2 weeks later
• oral lesions can occur but are rare

Question 3

Differentials when considering Pityriasis rosea?

Answer 3

• drug rash reaction
• urticaria (drug induced, allergic, viral)
• psoriasis
• tinea
• erythema multiforme
• pityriasis versicolour
• lichen planus
• secondary syphilis

Question 4

Management of Pityriasis rosea?

Answer 4

• reassure
• self limiting, should resolve within 3 months
• not contagious
• temporary pigment changes, no scarring
• low risk of recurrence

ITCH is main problem, some benefit from:

• 1% hydrocortisone
• emoillents
• topical menthol
• antihistamines