Antifungal resistance in cnlac1 possessing Cryptococcus neoformans isolated from domestic and feral pigeons in West Bengal, India

Abstract

Cryptococcus neoformans acts as a major etiology of human infections in immunocompromised, cancer and transplant patients. The present study was conducted to detect the occurrence and antifungal resistance of C. neoformans in domestic and feral pigeons in and around Kolkata, a metropolitan city in India with considerable size of pigeon population. Weathered droppings of domestic and feral pigeons (n=917) were collected from different pet bird shelters, different buildings and other places. Isolation and identification of C. neoformans was performed based on cultural, biochemical properties. Antifungal sensitivity of the confirmed isolates were performed according to standard CLSI protocols with seven antifungals and caspofungin. A total of 153(16.68%) samples were found positive for Cryptococcus neoformans var. neoformans. All the isolates possessed CNLAC1 outer gene in PCR. Antifungal sensitivity revealed marked resistance to amphotericin-B (33.33%), fluconazole (20.91%), flucytosine (11.11%), and ketoconazole (8.49%). This is of great concern as the study area (Kolkata) is a densely populated city and the birds are in close proximity to the people.