Heterozygous MZ alpha-1-antitrypsin deficiency in adults with chronic liver disease.

Pi phenotype was determined in 335 patients with liver diseases and compared with the results in 2830 healthy blood donors. Eleven of 335 patients had phenotype MZ (3.3%, compared with 2.9% in healthy blood donors (NS]. None of 53 patients with autoimmune chronic active hepatitis had the MZ phenotype, but it was found in 2 of 18 patients (11.1%) with cryptogenic cirrhosis, 3 of 78 (3.8%) with alcoholic liver cirrhosis, 2 of 36 (5.6%) with primary sclerosing cholangitis, and 1 of 26 (3.9%) with primary biliary cirrhosis. Altogether, 3 of 335 patients were homozygous for Pi ZZ and had cirrhosis. One of them (a male) developed a hepatoma and died. We conclude that the reported association between Pi MZ phenotype and chronic non-B active hepatitis does not seem to include patients with autoimmune chronic active hepatitis, whereas the possibility of an association between cryptogenic cirrhosis and the MZ phenotype cannot be excluded.