Alpha-1 Antitrypsin Deficiency Screening Using Serum Protein Electrophoresis

Background: Alpha-1 antitrypsin is encoded by the polymorphic SERPINA1 gene, with pathogenic variants causing alpha-1 antitrypsin deficiency. While being underrecognized, alpha-1 antitrypsin deficiency can be screened through serum protein electrophoresis (SPE) to detect mutations. This study aimed to evaluate the effectiveness of an SPE-based screening protocol for identifying SERPINA1 mutations and diagnosing alpha-1 antitrypsin deficiency. Methods: This study involved analyzing all SPE tests over one year at the Hospital Clínico Universitario "Lozano Blesa" (Zaragoza, Spain). Alpha-1 antitrypsin concentration was measured in samples with <3% alpha-1 globulin band, selecting those with <100 mg/dL as potential study participants. Participants provided blood samples for the genetic analysis of the SERPINA1 gene. Results: Out of 12,460 SPE tests analyzed, 175 had alpha-1 globulin bands <3%, and 70 cases had alpha-1 antitrypsin concentrations <100 mg/dL. Of these cases, 39 subjects participated in the study. The mean alpha-1 antitrypsin concentration was 78.8 mg/dL. Genetic analysis showed 87.2% had SERPINA1 mutations, with common genotypes being PI*MS, PI*MZ, and PI*SZ. Conclusions: This study confirms the efficacy of SPE as a potential screening strategy for detecting mutations in the SERPINA1 gene. It can facilitate opportunistic diagnosis of alpha-1 antitrypsin deficiency, promoting early detection and treatment.