CD79A and bronchiectasis: When identifying NTM-PD in the bronchiectasis cohort (n = 240), antiglycopeptidolipid core IgA antibody level showed 61.5% sensitivity, 98.6% specificity, and 43.9 positive likelihood ratio at the manufacturer’s cut off (0.7 U/mL) and 80.8% sensitivity, 88.3% specificity, and 6.9 positive likelihood ratio at an optimal cut off suggested in this study (0.4 U/mL).