Heterozygous α1‑antitrypsin deficiency in liver transplant candidates

It is estimated that in about 1% of all liver transplant candidates liver cirrhosis is caused by hereditary homozygous α1‑antitrypsin (AAT) deficiency.

The aim of the study was to evaluate the role of heterozygous AAT deficiency in the development of liver cirrhosis leading to liver transplantation.

In the years 2009-2011, we conducted a prospective study of 304 consecutive patients (men, 57%) scheduled for orthotopic liver transplantation. AAT phenotyping and the clinical assessment of hepatic and cardiopulmonary functions were performed in all subjects.

The most common causes of liver cirrhosis were viral hepatitis (21%) and alcohol abuse (12%). Normal protease inhibitor (Pi) MM phenotype was observed in 284 patients. The PiMZ phenotype was detected in 11 subjects (4%), which indicates its higher prevalence in patients with liver cirrhosis compared with the general population (2%). PiMS phenotype was found in 6 patients (2%), and this value was similar to that observed in the Polish population. In 3 patients, less common phenotypes were observed: MP, IM, and MX.

The PiMZ phenotype may be an independent risk factor for the development of liver cirrhosis along with the most common causes, namely, viral hepatitis and alcohol abuse.