Prevalence of Aspergillus Infection in Various Clinical Samples with a Special Reference to Black Grain Eumycetoma Caused by Aspergillus nidulans in a Tertiary Care Hospital in Eastern India

Introduction and study aim: Mycology has become an extremely challenging study of infections caused by a taxonomically diverse array of opportunistic fungi. Being a widespread soil saprophyte and plant pathogen, Aspergillus species is responsible for superficial and subcutaneous infections, allergic broncho-pulmonary aspergillosis, and another life-threatening invasive aspergillosis. So, proper identification of Aspergillus becomes necessary to ascertain its role in the various infectious etiologies. Patients and Methods: Various clinical samples received in the Mycology lab from November 2022 to May 2023, like nails, urine, respiratory samples, pus, tissue from Functional Endoscopic Sinus Surgery (FESS) and suspected Madura foot were subjected to 10-20% KOH mount followed by fungal culture to confirm the isolate. Slide culture & Banana peel culture were also done as needed. Cultural characteristics & arrangement of phialides & metulae around the vesicle remain the main identifying points to confirm the isolates. Results: Out of 32 (10.7%) Aspergillus sp. from 300 samples, A. flavus (28.1%) was the highest followed by A. fumigatus & A. niger (25.0%); whereas A. nidulans & A. terreus isolated as lowest (6.2%). Regarding case distribution, the lowest % of cases were found in the 6-12-year age group (3.1%), whereas the highest % of cases were found in the 13–50-year age group (71.9%). Conclusion: Diagnosis of invasive aspergillosis remains difficult clinically due to its wide spectrum of invasion & varied clinical presentation. So, emphasis on fungal culture plays an important role in diagnosing & speciation of Aspergillus infections in various samples.