P419 Galactomannan enzyme immunoassay in invasive pulmonary aspergillosis: a cross sectional study in 2021 in a New Delhi

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMObjectiveThis study aims to determine the role of GM EIA in the diagnosis of IPA as per revised EORTC/MSG 2019 criteria.Material and MethodsA prospective cross-sectional study was performed on 87 children (from 1 to 12 years) admitted to pediatric hematology ward from Oct 2020 to February 2022. Serum of these patients was collected and GM EIA was performed using BIO-RAD Platelia™ Aspergillus Ag. Clinical, mycological workup (potassium-hydroxide mount, fungal culture) was done and furthermore, these patients were classified into proven, probable, and possible IA as per EORTC-MSG guidelines, 2019. Galactomannan indices (GMI) measured in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were validated with revised EORTC -MSG, 2019 of IPA.ResultsA total of 53 patients out of 87 were categorized into probable IPA with routine mycological findings. On culture Aspergillus flavus was the most common pathogen, identified in 56% (25), followed by A. fumigatus 31.8% (14), A. niger 9% (4), etc. 44 (50.5%) had GMI value of >0.7, 9 (10.3%) in the range of 0.5-0.7 and 34 (39%) had GMI <0.5.The maximal Youden index ‘J’ [95% confidence interval (CI) of 0.4167-0.6875] was calculated as 0.678 and sensitivity, specificity, PPV, and NPV in IPA were calculated corresponding to a GM index of >1.0, 0.7, 0.5 to determine the best cutoff point. The best cutoff was found to be 0.695 where in the 84.1% and specificity was 83.7% respectively.ConclusionGM EIA can prove as an excellent diagnostic test for IPA when done in addition to culture from nonsterile sites in high-risk populations like pediatric patients with hematological malignancy. This study reinforces the definition of the probable category of EORTC-MSG criteria, 2019 in overall diagnosis, prognosis, and management of IPA in pediatric patients with hematological malignancy.