Background and Aim: Patients suspected of Alpha 1-Antitrypsin (A1AT) ab-normality based on low serum concentration are routinely confirmed through polymerase chain reaction (PCR) testing of peripheral blood. Genotyping for-malin-fixed paraffin-embedded (FFPE) tissue is a novel approach that could aid in detecting variant A1AT. We performed qPCR on FFPE liver explants with Periodic Acid Schiff after Diastase (PASD)- and A1AT-positive globules to confirm and estimate the frequency of A1AT deficiency in transplant cases.
Material and Methods: Eighteen (12.68%) of 142 patients with end-stage liver disease showed PASD/A1AT positive globules. FFPE of the explants was tested through qPCR to detect S and Z alleles. A second age- and sex-matched control group consisting of five liver transplant patients with neg-ative globules was included in the study.
Results: qPCR assay was successful with all the samples meeting QC pa-rameters. All patients included in the study elucidated Z allele variants; 2 homozygous (11.1%) and 16 heterozygous (88.9%). The control group demonstrated normal wild-type MM allele.
Conclusion: Screening for A1AT deficiency using serum levels is not suffi-ciently sensitive to detect deficiency, especially in carriers. If A1AT testing was not performed preoperatively and the risk is high based on the PASD/A1AT-positive globules in the explants, then molecular testing of FFPE tis-sue can be a viable method for confirming the diagnosis.