Porphyria cutanea tarda-a genetic disease? A biochemical and fluorescence microscopical study in four families.

Abstract

. The siblings of patients with clinically manifest porphyria cutanea tarda (PCT) have been investigated by chemical analysis of urinary and faecal porphyrin excretion and by fluorescence microscopical examination of smears from fine needle biopsy specimens of the liver. Four families and one alcoholic and one non-alcoholic control group were studied. In two families red porphyrin fluorescence was demonstrated in 5 out of 15 asymptomatic siblings, and one sibling who refused liver biopsy was found to have a clinically manifest PCT. In the two other families no porphyrin abnormality could be demonstrated in the 7 asymptomatic siblings. In the control group comprising 36 non-alcoholic subjects no porphyrin fluorescence could be demonstrated, but in the alcoholic control group of 59 subjects liver porphyrin fluorescence was found in two. Alcoholic abuse was common in the two families in which several members had porphyrin abnormalities indicating latent PCT. In the group of alcoholics liver porphyrin fluorescence was uncommon. Hence the present results indicate that PCT might be a genetic disease.