Diagnostic Accuracy of Beta-D-Glucan and Galactomannan as Fungal Markers in the Detection of Positive Fungal Cultures among Immunocompromised Patients

As fungal infections pose a significant threat to immunocompromised patients, necessitating timely and accurate diagnostic approaches for effective management, non-invasive diagnostic markers are direly needed to detect the presence of fungi during the early stage of the infection. Objectives: To determine the diagnostic accuracy of Beta-D-Glucan and Galactomannan as fungal markers in the detection of positive fungal cultures among immunocompromised patients. Methods: This cross-sectional study was conducted at the Intensive Care Units of Shifa International Hospital, Islamabad, from April 2024 to July 2024. 57 immunocompromised patients of both genders with an age range of 12 to 80 years, who had positive fungal cultures were included in the study via Non-probability, consecutive sampling while patients who were taking any antifungal medications were excluded. Diagnostic accuracy, sensitivity and specificity of Beta-D-Glucan and Galactomannan were calculated by comparing these assay results against the gold standard of CSF analysis of fungal culture. Results: The Beta-D-Glucan and Galactomannan assays showed a specificity of a moderate nature for both assays, slightly higher for Beta-D-Glucan (77.78%) than Galactomannan (72.73%), with a high sensitivity of 92.31% for Beta-D-Glucan and 90.20% for Galactomannan. Overall, the diagnostic accuracy was high for both assays, with Beta-D-Glucan at 96.49% and Galactomannan at 94.74%. conclusions: It was concluded that while the Beta-D-Glucan assay is more sensitive, the Galactomannan assay appears to be more specific. Thus the combined use of both tests enhances diagnostic accuracy for detecting fungal infections in immunocompromised patients.