Porphyria cutanea tarda (PCT) is one of the inborn porphyrinopathies. It is characterized by abnormal porphyrin synthesis and excretion, cutaneous photodynamic activity, fragility of the skin, and, usually, evidence of liver disease. Schmid, Schwartz, and Watson 1 termed porphyria cutanea tarda and acute intermittent porphyria as hepatic porphyrias, a group of disorders very distinct from congenital (erythropoietic) porphyria. Waldenström2 recognized two forms of porphyria cutanea tarda. One form is familial (PCT hereditaria) and becomes clinically manifest shortly after puberty. It may occasionally be complicated by features of acute porphyria, including the excretion of porphobilinogen in the urine. The other form (PCT symptomatica) becomes manifest later in life and is associated with alcoholism or alcoholic cirrhosis and, in rare instances, with tumors of the liver.
The treatment of porphyria cutanea tarda has been generally disappointing. However, some reports of treatment with dimercaprol (BAL) or edathamil (ethylenediaminetetraacetic acid)3-5 have been