First isolation and molecular characterization of Cryptococcus neoformans var. grubii in excreta of birds in the urban perimeter of the Municipality of Popayán, Colombia.

Background: Cryptococcosis is a systemic opportunistic mycosis, caused by Cryptococcus neoformans and Cryptococcus gattii, which affects mainly the central nervous system of immunocompromised patients; no reports have been made on the isolation of the fungus from the environment of Popayán, Colombia.
Aims: The main objective of this investigation was to determinate the incidence of C. neoformans in the urban perimeter in the City of Popayán, Colombia.
Methods: A total of 303 samples from droppings of Columba livia and Bubulcus ibis were collected between September 2012 and June 2013. The samples were processed by conventional techniques; identification of colonies was performed by biochemical tests, and molecular patterns were determined by PCR fingerprinting with the primer (GTG) ₅ and restriction fragment length polymorphism (RFLP) of the gene URA ₅ .
Results: A total of 118 (38.94%) samples were positive for Cryptococcus in excreta of C. livia, and 361 strains belonging to Cryptococcus neoformans var. grubii were isolated. From the latter, 99.2% corresponded to the molecular pattern VNI and 0.8% to VNII, with an increased occurrence (24.4%) at a temperature of 22.5°C and a humidity of 60.8%. The excreta of B. ibis did not show the presence of the fungus.
Conclusions: C. livia excreta is a key environmental niche for C. neoformans var. grubii, type VNI, supporting growth and reproduction, and serving as a major source of infection for susceptible populations in Popayán. This represents the first report on the isolation of the agent of cryptococcosis from the environment in this region, with a significant prevalence in bird excreta.
(Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)