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What is A 40 year old farmer with a history of recurrent attacks of porphyria complains of itching when exposes to the sun and maculopapular rash on sun exposed areas, his symptoms are exaggerated in the summer. The diagnosis is – and explain in detail?
This farmer has :-

Porphyria
Skin manifestations (Photosensitivity)
No neuropsychiatric manifestations

Porphyrias with only skin manifestations are porphyria cutanea tarda, erythropoietic protoporphyria, congenital erythropoietic porphyria.