Bullous skin lesions in a patient undergoing chronic hemodialysis.

ABSTRACT

Porphyria cutanea tarda (PCT) is a vesiculobullous skin disorder characterized by a defect in heme biosynthesis. Reduced activity of the hepatic enzyme uroporphyrinogen decarboxylase (URO-D) results in accumulation of photosensitive porphyrins; this ultimately leads to the skin fragility and blistering that is characteristic of this disease. The majority of cases of PCT are associated with acquired deficiencies of the enzyme URO-D, secondary to hepatic injury precipitated by medications or infections. Less commonly, PCT has been documented in patients with end-stage renal disease. The pathogenesis of PCT in long-term hemodialysis (HD) has been attributed to many factors, but the following mechanisms have been implicated (i) decreased hepatic URO-D activity due to suppressive effects of iron and other hepatotoxins and (ii) poor porphyrin clearance by renal replacement therapies. We report a case of PCT that developed in a patient on maintenance HD for 4 years. He had a history of hepatitis C and evidence of iron overload. However, as the patient was anemic, therapeutic phlebotomy was problematic and therefore erythrocyte-stimulating agents were maximized to mobilize iron stores and allow phlebotomy. With this treatment, the patient's skin lesions improved in conjunction with decreasing ferritin levels.