A 16 year old boy presented with asymptomatic, multiple erythamatous annular lesions with a collarette of scales at periph-ery of the lesions present on the trunk. The most likely diagnosis is:
C i.e. Pityriasis rosea Pityriasis rosea is a self limiting disorderQ of unknown etiology, with a suspected association with Herpes virus 7 and 6Q. It presents with development of usually asymptomatic (i.e. no prodromal or constitutional system), sharply (well) demarcated, larger (2-6 cm), annular (oval-round), erythematousQ (red to brown) lesion k/a primary/herald/mother patch mostly located on trunk in children and young adults (10-35 yrs)( 2. Similar but smaller secondary eruptions appear in crops at interval of usually 2 weeks distributed along lines of cleavage in christmas (fir) tree appearanceQ. Lesions demonstrate fine (cigarette paper) collarette of scaleQ just inside the peripheray of plaque.
Pityriasis versicolor
Pityriasis alba
Pityriasis rosacea
Pityriasis rubra pilaris