Study of alpha1-antitrypsin phenotypes frequencies in patients with primary antibody deficiency.

Primary antibody deficiencies are the most frequent primary immunodeficiency disorders. Bronchiectasis as a feature of these disorders may be developed due to some factors such alpha-1- antitrypsin deficiency. In order to determine the prevalence of two common alpha-1-antitrypsin deficiency alleles (PIZ and PIS) in Iranian patients with antibody deficiency, this study was performed. The prevalence of PIM, PIS, and PI*Z allele combinations was determined in 40 patients with primary antibody deficiency (with and without bronchiectasis) and compared with 60 healthy control subjects. Phenotyping was performed by isoelectric focusing. The phenotype frequencies among patients were as follow: M in 92.5%, S in 2.5% and Z in 5%. There was not any significant difference in distribution of alleles or phenotypes between patients and control subjects. Moreover, no significant difference was found between patients with and without bronchiectasis. We did not find evidence to support an association between alpha-1-antitrypsin phenotypes and primary antibody deficiencies in a small, controlled study. Larger studies will be required to clarify the relationship between alpha-1-antitrypsin genotype and susceptibility to bronchiectasis in patients with antibody deficiency.