The role of (1,3)-beta-D-glucan (BDG), as noninvasive technique for detection of invasive fungal infection (IFI)

Background: BDG is found in the cell walls of most fungi (eg, Candida, Aspergillus, Fusarium, Pneumocystis jirovecii). Serum BDG levels is high in the presence of a fungal infection. Its high serum levels may be detected before development of clinical symptoms and even prior to isolation or identification of the fungal organism via routine laboratory methods. Objectives: evaluate the performance of serum (1.3) beta -D glucan BDG in comparison with blood culture for diagnosis of the invasive fungal infections with Candida species. Methodology: The study was conducted on 50 patients divided in 3 group first group 20 patients with prolonged stay in ICU receiving broad spectrum antibacterial treatment, and second group 20 patients with diabetic foot and third group 10 patient healthy subjects with matched sex and age. All patients were subjected to full history taking, clinical examination and laboratory investigations Blood was examined with conventional methods (, Gram stain and culture on fungal media) and serum (1,3) beta -D-glucan was determined by ELISA. Result: The average serum concentration of BDG was higher in group II (121.25±88.9 pg/ml than group I (115.5±90.9 pg/ml), however there is no statistically significantly difference between group I and groupII, the mean value of serum (1.3 beta D glucan) in patient with positive blood culture were significantly higher than those with negative blood culture there is significant relation between blood culture and the level of(1,3)beta D-glucan in serum. Blood culture could be considered as marker for detection of invasive fungal infection with sensitivity, specificity, PPV and NPV of, 46.43%, 100%, 100% and 11.76% respectively however (1.3) D glucan can detect invasive fungal infection with sensitivity, specificity, PPV and NPV of, 88.46%, 100%, 100% and 40%. Conclusion: Our results suggest that a positive (1,3)beta-D-glucan assay could be a superior test for diagnosis of candidemia in addition to the blood culture