Porphyria cutánea tarda (PCT) results fi'om an anomaly of hepatic haem metabolism. However, little is known about the possible association between PCT and congenital haemolytic disorders implicating increased erythrocyte turnover. We report here the first case of PCT associated with hereditary spherocytosis (HS) and discuss the potential pathophysiological implications of these combined conditions.
CASE REPORTA 52-year-old woman was referred for blistering lesions and skin fragility with bruises occurring after minor trauma, located on sun-exposed areas and evolving since the previous summer. Her face was slightly greyish, a clinical manifestation she had not noticed previously. Her medical history was remarkable for hereditary spherocytosis with splenectomy during her first year of life. She had been taking substitutive hormone therapy during the previous 5 years, a combination of topical oestrogen and oral progesterone. She denied any excessive alcohol consumption. Clinical examination revealed the presence of rare blisters, along with crusts, erosions and scars, on the dorsum of her hands. Histological examination of a bullous lesion revealed subepidermal blister and mild inflammatory infiltrate surrounding ecstatic vessels in the papillary dermis, reminiscent of PCT. Biological investigations showed classical signs of splenectomized hereditary spherocytosis: spherocytes and Jolly's bodies on the blood film, thrombocytosis (related to splenectomy), normal number of reticulocytes, decreased haptoglobin (0.11 g/1, normal > 0.3 g/1) with a negative Coombs test. Osmotic fragility tests including the pink test showed pathological haemolysis. Flow cytometry showed the characteristic decrease in band 3 (a red cell membrane protein) in the eosin-5-maleimide test. There were no clues for chronic viral hepatitis, but hyperferritinaemia (1,139 ng/ml, normal < 200 ng/ml), elevated transferrin saturation up to 79.4% and fully confirmed PCT with total urinary porphyrins up to 3,762 nmol/24 h (normal <300 rmiol/24 h) and a predominant increase of uroporphyrins (40% of the total urinary porphyrins, i.e.