Alpha-1 antitrypsin deficiency in children with chronic lung diseases

Objective. To analyze the role of Pi gene polymorphisms in the development of chronic nonspecific lung diseases, bronchial asthma, and cystic fibrosis, as well as their impact on the disease course among Russian children compared to healthy controls. Patients and methods. This study included 303 patients that were randomly selected from all patients treated in the Department of Pulmonology and Allergology of the National Medical Research Center of Children's Health. The sample included patients with chronic nonspecific lung diseases (CNSLD) (such as chronic obstructive bronchitis, emphysema, bronchiectasis, and obliterating alveolitis) and patients with bronchial asthma and cystic fibrosis. DNA samples from patients and healthy controls were analyzed using molecular methods, including RFLP and real-time PCR with subsequent statistical analysis. Results. The frequency of mutant Pi*S and Pi*Z alleles was 5.8% among CNSLD patients. However, patients with pulmonary cystic fibrosis and controls had no pathological alleles. The heterozygous 1331A allele was identified in 16.5% of all patients. In patients with bronchial asthma, its frequency was 21.2%, which was significantly higher than in other groups of patients (10.1% and 11.1%, respectively) and controls (9.9%). Conclusion. Our findings may indicate the involvement of mutant Pi*S and Pi*Z alleles in the development of multifactorial lung diseases. We shouldn’t ignore the role of the 1331A allele in aggravating bronchial asthma. Presumably, the 1331A mutation in the Pi gene can modify the course of any monogenic and multifactorial lung diseases. Key words: SERPINA1; alpha-1 antitrypsin deficiency; CNSLD,