Lack of association between porphyria cutanea tarda and alpha 1-antitrypsin deficiency.

Objective: To determine whether alpha 1-antitrypsin deficiency is involved in the pathogenesis of chronic liver disease in patients with porphyria cutanea tarda and in their recently described high prevalence of hepatitis C virus infection.

Design: Consecutive patients diagnosed as having porphyria cutanea tarda and chronic liver disease.

Setting: A northern Italian hospital.

Methods: alpha 1-antitrypsin phenotypes were characterized by isoelectric focusing and the results confirmed by DNA analysis in 63 Italian patients with porphyria cutanea tarda.

Results: alpha 1-antitrypsin phenotypes different from the normal one were found in 13% of the patients. This prevalence did not differ from that in control subjects (9%). Clinical characteristics of patients with porphyria cutanea tarda with normal or altered alpha 1-antitrypsin phenotype, including age of presentation of the disease, prevalence of hepatitis C virus infection, liver histology, prevalence of iron overload and hepatocellular carcinoma occurrence, did not differ significantly.

Conclusion: alpha 1-antitrypsin does not seem to play a role in the pathogenesis of chronic liver disease and hepatitis C virus infection in patients with porphyria cutanea tarda. Patients in whom the two defects coexist do not have a more severe disease.