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What is A 25 year old male presents with multiple erythematous annular plaques with peripheral collarette of scales arranged predominantly over trunk. What is the most probable diagnosis? and explain in detail?
Pityriasis Rosea is a self limiting papulosquamous dermatoses of unknown aetiology characterised by Herald patch, annular plaque with peripheral collarette of scales on the trunk and secondary lesions arranged in Christmas tree/fir tree appearance. Treatment is usually symptomatic. It resolves in about 8-10 weeks. Ref: Illustrated Synopsis of Dermatology and STD's By Neena Khanna, Pages 50-51