Candida species isolated from pigeon (Columbia livia) droppings may express virulence factors and resistance to azoles

• Published in: Veterinary microbiology 2019-08, Vol.235, p.43-52
• Main Authors: Magalhães Pinto, Luciana, de Assis Bezerra Neto, Francisco, Araújo Paulo de Medeiros, Mariana, Zuza Alves, Diana Luzia, Maranhão Chaves, Guilherme
• Format: Article
• Language: English
• Subjects: Air conditioners; Antifungal agents; Antifungal resistance; Azoles; Beaks; Biofilms; Birds; Candida; Candidaspp; Clinical isolates; Columbia livia; Conditioning; Cryptococcosis; Epithelial cells; Feathers; Fluconazole; Fungal infections; Fungi; Fungicides; Gastrointestinal tract; Hemolysins; Heterocyclic compounds; Immunocompromised hosts; Itraconazole; Lytic enzymes; Micafungin; Pigeon droppings; Pigeons; Resistance factors; Species; Virulence factors; Yeasts
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2019.05.022

•Candida spp. of medical interest may be isolated from pigeon droppings with higher prevalence than Cryptococcus spp.•Candidaspp. recovered from fungal droppings may adhere to epithelial cells, have the ability to form biofilms and secrete lytic enzymes.•Candida spp. recovered from fungal droppings may show drug resistance to fluconazole and itraconazole without any known previous exposure. Even though it is widely known that Cryptococcus spp. may transmit cryptococcosis trough aerosol formed when dried birds (mainly pigeons) droppings are dispersed and become airborne, little is known about the role of these birds in harboring other pathogenic yeasts in their gastrointestinal tract, feathers and beaks, specifically because these animals often stay and reproduce close or even above air conditioner units. Here we evaluated the prevalence of pathogenic yeasts isolated from pigeon droppings collected in the outside area of a University Hospital in Brazil. We also aimed to investigate the pathogenic potential and antifungal susceptibility of Candida species of medical interest isolated from these samples. Therefore, we performed the evaluation of virulence factors attributes expression in vitro, including the ability to adhere to human buccal epithelial cells and biofilm formation and to produce lytic enzymes, such as phospholipases, proteinases and hemolysins. Antifungal susceptibility testing against fluconazole, itraconazole, amphotericin and micafungin was also performed. The Candida genus was the most prevalent in our study, with several medically important species being isolated. Of note, these strains were able to express several virulence factors in vitro, clearly showing their pathogenic potential. Our study was able to demonstrate that Candida spp. isolated from pigeon droppings may express virulence factors in the same manner of clinical isolates, suggesting a pathogenic potential for these yeasts. The fact these strains were collected from the outside area of a tertiary hospital may be of interest, because they may be a source of infection, specifically to immunocompromised hosts.