Background: Studies have been conducted to determine the relationship between environmental and clinical strains of Cryptococcus neoformans. Methods: The relationship between clinical and environmental strains of C. neoformans var. neoformans were investigated based on varieties, serotypes, molecular epidemiology and antifungal susceptibility for amphotericin B (AMB) 5-flucytosine (5-FC), fluconazol (FCZ) and itraconazol (ITZ) according the NCCLs recommendation. Serotyping was performed by Crytpo Check (Iatron, Jp). Forty-five clinical strains and 55 environmental strains isolated from pigeon drops of C. neoformans from a limited area in Brazil were investigated. Clinical and environmental strains were obtained from rural and downtown areas during one year period, concomitantly. Results: All strains were C. neoformans var. neoformans serotype A. The MIC 90 (mg/ml) for clinical and environmental strains had the same values: AMB: 1; 5-FC: 2; FCZ: 4 and ITZ: 0.25. Molecular typing by PFGE showed five and 14 distinctive electrophoretic karyotypes were observed for environmental and clinical strains, respectively. Three clinical strains with distinctive EK profiles were also identified among the environmental strains. No correlation was present among clinical and environmental EK profiles and MIC levels of the tested antifungal drugs. Conclusions: A higher number of EK profiles were observed in clinical than in environmental isolates suggesting that the strains may vary during different periods of the year. Our results support the hypothesis that human infection with C. neoformans var neoformans can be acquired from pigeon dropping in rural and urban areas. FAPESP grants 99/10697-0 and 99-08072-1.
Full conference title:
43rd Interscience Conference on Antimicrobial Agents
- ICAAC 43rd