Abnormal Porphyrin Metabolism and Polymorphic Photodermatitis

THE diagnosis of cutaneous porphyria is suggested by the clinical findings of photosensitivity, hyperpigmentation, hirsutism and increased fragility of the skin. This diagnosis is confirmed by the demonstration that the urinary and fecal excretion of porphyrins is abnormally large; in urine there is usually excess uroporphyrin whereas in feces there is excess coproporphyrin and protoporphyrin.1 For many years it has been noted that a large variety of cutaneous lesions (macules, papules, plaques, wheals, vesicles, bullae, eczematous dermatitis and so forth) develop in certain persons after exposure to sunlight. The nomenclature of such abnormal cutaneous responses has depended . . .