Antifungal Susceptibility Profile of Aspergillus Strains Isolated From the Lower Respiratory Tract in Eastern Indian Patients: A Hospital-Based Study

Abstract

Respiratory aspergillosis refers to a range of infections, from allergic to chronic and invasive, which can be life-threatening and are primarily caused by Aspergillus fumigatus and Aspergillus flavus. Other species, including Aspergillus terreus, Aspergillus nidulans, and Aspergillus versicolor, have also been implicated in respiratory infections. Treatment for chronic to invasive pulmonary aspergillosis typically involves azole antifungal drugs, although studies have shown varying minimum inhibitory concentrations (MIC) for these medications, with a growing concern over voriconazole resistance. During the period from August 2022 to May 2024, characteristic hyphae were detected in 7.2% of lower respiratory samples, with culture positivity in 12.8%, including early morning sputum and bronchoalveolar lavage fluid samples. A. flavus (n = 282) was the most frequently isolated species, followed by A. fumigatus (n = 86). Additionally, a seasonal trend was observed for Aspergillus infections, with peaks in April and September. The MIC of itraconazole, voriconazole, posaconazole, amphotericin B, ravuconazole, and caspofungin were assessed for the isolated Aspergillus species. A higher MIC of amphotericin B was observed against A. flavus and A. terreus, whereas azoles exhibited a relatively lower MIC. Caspofungin and posaconazole exhibited the lowest MIC against the isolated Aspergillus species. Therefore, it is crucial to identify the causative fungi and determine the antifungal MIC for Aspergillus species responsible for lower respiratory tract infections. This study emphasizes the significance of respiratory aspergillosis in TB-endemic regions of Eastern India. © 2025 The Author(s). MicrobiologyOpen published by John Wiley & Sons Ltd.