ABSTRACT
This chapter presents the case study of a 49-year-old man presents to the dermatology out-patient clinic with a 6-month history of a gradually worsening rash on the dorsi of his hands. He has no history of previous skin problems or atopy. Over the dorsi of his hands are scattered tense vesicles and bullae with multiple erosions, scarring, milia and pigmentation. The patient was not aware that he was photosensitive due to the insidious onset of his skin eruption over many months. The patient was diagnosed with porphyria cutanea tarda (PCT) which usually presents between the 3rd to 5th decades. The porphyrias are diseases in which specific enzyme deficiencies lead to the accumulation of intermediate metabolites in the porphyrin biosynthesis pathway. A skin biopsy reveals subepidermal bullae. Deficiency of the enzyme uroporphyrinogen decarboxylase is responsible for PCT, which may be inherited or acquired.
