Performance of serum galactomannan in patients with allergic bronchopulmonary aspergillosis

Summary Few studies have evaluated the performance of serum galactomannan (GM) in patients with allergic bronchopulmonary aspergillosis ( ABPA ). Herein, we analyse the diagnostic performance of serum GM in ABPA . Consecutive subjects with ABPA and asthma underwent GM estimation using the Platelia assay (Bio‐Rad Laboratories). An optical density index of >0.5 was considered positive. One hundred and twenty subjects (70 ABPA , 50 asthma) with a mean ( SD ) age of 33.0 (13.1) were included in the study. The serum GM antigen was positive in 18 (25.7%) subjects with ABPA compared to 9 (18%) subjects with asthma without ABPA ( P  = 0.32). The sensitivity of the serum GM antigen test in patients with ABPA was 25.7% [95% confidence intervals ( CI ), 16–38] while the specificity was 82% (95% CI , 69–91). The positive and negative predictive values were 66.7% (95% CI , 46–84%) and 44.1% (95% CI , 34–55), respectively. The area under the ROC curve was 0.54 (95% CI , 0.44–0.64). The sensitivity increased and the specificity decreased with decreasing the serum GM cutoff, and vice versa. The results of this study suggest that serum GM estimation has a limited role in the diagnostic workup of patients with ABPA .