First report of environmental isolation of Cryptococcus neoformans and other fungi from pigeon droppings in Makkah, Saudi Arabia and in vitro susceptibility testing

ObjectiveTo verify the occurrence of Cryptococcus neoformans (C. neoformans) and other fungi in samples of pigeon droppings collected from Makkah city, Saudi Arabia.MethodsOne hundred and twelve withered pigeon dropping samples were collected from 12 different districts. Using the dilution plate technique, samples were cultured on Sabouraud dextrose agar and esculin agar. Colonies were examined microscopically and C. neoformans identification is confirmed by India ink preparation, observation of urease activity and brown pigmentation on esculin medium. Susceptibility patterns of five yeast species and four molds against five antifungal drugs were tested using agar disk diffusion method.ResultsC. neoformans was recovered from 38 samples (34%). Na'aman valley was recorded to be the highest contaminated site (66.7%) with C. neoformans, while the samples collected from Al Awaly district were considered as the lowest contaminated samples (6.7%). Also, twenty species related to sixteen genera of fungi other than C. neoformans were recovered from which, three yeast genera were recorded. The antifungal susceptibility testing showed that the nine tested fungal species were sensitive to Mycosat, while Fungican exerted inhibition zones of four species only. C. neoformans was moderately sensitive towards all tested compounds but it can resist Flucoral where no inhibition zone could be detected.ConclusionsOur results are considered to be the first report on the environmental prevalence of C. neoformans in pigeon feces in Makkah, Saudi Arabia. The data indicated that pigeon droppings can be considered as a potential source of this basidiomycetous yeast in addition to other fungal species in this region.