A preliminary study on the measurement of (1,3)-β-D-glucan in bronchoalveolar lavage for the diagnosis of pulmonary fungal infections

Abstract

To explore the measurement of (1,3)-β-D-glucan bronchoalveolar lavage fluid (BALF) for the diagnosis of pulmonary fungal infections. A total of 135 patients in the General Hospital of Tianjin Medical University from February 2010 to February 2011 were enrolled. There were 34 cases of confirmed or clinically diagnosed pulmonary fungal infections, 53 cases of bacterial pneumonia, and 48 cases of non-infection diseases. All patients underwent BAL and the BALF samples were obtained. (1,3)-β-D-glucan content (G test), in BALF and plasma were tested and the data were analyzed statistically by Mann-Whitney while the receiver operating characteristic curve (ROC curve) was established, from which the best threshold of the 2 G tests was derived. The median of BALF G test in the fungal infection group, pneumonia group and non-infection group was 281, 28 and 10 ng/L, respectively; the level in the fungal infection group being significantly higher than those of the other 2 groups (P < 0.001), but no significant difference being observed between the pneumonia group and the non-infection group (P > 0.05). The median of plasma G tests in the fungal infection group, the pneumonia group and the non-infection group was 27, 10, and 5 ng/L, respectively; the level in the fungal infection group being significantly higher than those in the other 2 groups (P < 0.001), but there was no significant difference between the pneumonia group and the non-infection group (P > 0.05). The best threshold of BALF G test was 67 ng/L, while the best threshold of G test of plasma was 17 ng/L. As compared to G test of plasma, G test of BALF may be more accurate, and have a higher clinical value for the earlier diagnosis of pulmonary fungal infections.