Introduction: Candida species are the most common cause of fungal infections in hospitalized patients and the fourth most common isolate recovered in cases of nosocomial bloodstream infection in the US. Recent studies have reported a relative reduction in the rates of infection caused by C. albicans and a shift towards non-albicans Candida spp. Data on the distribution and susceptibility of Candida spp. from children’s hospitals is limited. Methods: A total of 179 pediatric clinical Candida spp. isolates from 2003 were identified.Broth microdilution MIC’s for amphotercin B (Amb), fluconazole (Flu), voriconazole (Vori), caspofungin (Cas), Posaconazole (Pos), and Ravuconazole (Rav) were performed according to the NCCLS approved standard M27-A. All drugs tested were obtained as standard reference powders and the NCCLS M27-A recommendations for dilutions of antifungal agents were followed. Microdilution trays containing serial dilutions of the antifungal agent in RPMI 1640 buffered with 0.165M MOPS were prepared in-house and stored at -800C until ready for use. MIC’s were determined after incubation (350C ambient air in a moist chamber) at both 24h and 48h. For amphotericin B, the endpoint was defined as the lowest concentration that completely inhibited growth. For all other agents tested the MIC was defined as the lowest concentration in which a prominent decrease in turbidity was observed. C. krusei ATCC 6258 and C. parapsilosis ATCC 22019 were used as QC reference strains. QC was performed each time isolates were tested and their results were consistently within the acceptable ranges Conclusion: In our study we found C albicans to be the most frequent isolate 44% (77/176). C parapsilosis constituted the second most frequent isolate (57/176). The high isolation rate of C parapsilosis most likely reflects the large number of isolates from NICUs, where C parapsilosis has previously been reported to be a frequent Candida species found. The other species identified are similar to those seen in the adult high risk population. Am B, Flu, Vori, and Cas all demonstrated good activity against these isolates with the exception of Flu against C. glabrata, C.tropicalis and a few C. albicans. Pos and Rav both demonstrated excellent activity against all isolates.
Full conference title:
14th Annual Focus on Fungal Infections
- FFI 14th (2004)