Efficiency of A fumigatus-specific IgG and galactomannan testing in the diagnosis of simple aspergilloma.

Background: An early diagnosis of chronic pulmonary aspergillosis (CPA) at the stage of simple aspergilloma (SA) remains a challenge in low- and middle-income countries, where imaging may not be routinely available.

Objective: We investigate the role of Aspergillus fumigatus-specific IgG in serum, and galactomannan (GM) in bronchoalveolar lavage fluid (BALF) and serum for the diagnosis of SA.

Methods: We included 46 consecutive treatment-naïve subjects with SA. The 81 controls were subjects of treated pulmonary tuberculosis with residual radiological abnormality and minimal symptoms; and subjects with pulmonary disorders other than CPA who underwent bronchoscopy. The diagnosis of SA was based on consistent clinical features along with radiological manifestations (cavity with fungal ball).

Results: Using receiver operating characteristic (ROC) curve analysis, the best cut-off value for A fumigatus-specific IgG was 27.3 mgA/L (AUROC, 0.839; sensitivity, 63.5%; specificity, 98.3%). The best cut-off value for serum and BALF-GM was 0.7 (AUROC, 0.636; sensitivity, 32%; specificity, 96.2%) and 2.5 (AUROC, 0.833; sensitivity, 63.7%; specificity, 97.1%), respectively. A combination of A fumigatus-specific IgG (>27 mgA/L) or serum GM (≥0.7) or BALF-GM (≥2.5) had a sensitivity and specificity of 82.6% and 96%, respectively.

Conclusions: A combination of serological tests has the best sensitivity in diagnosing SA. More studies are needed to confirm our findings.