Objectives: Invasive trichosporonosis caused by yeast Trichosporon beigelii often results in rapid, widespread dissemination and high mortality because diagnostic and therapeutic means have not been established well. The authors report a case of fatal T. beigelii fungemia in a 28-year old woman with acute leukemia and neutropenia. The patient was not on antifungal therapy before this episode of fungemia. Methods: During five days seven blood samples were collected. All samples were inoculated on Sabouraud dextrose broth and agar and incubated at 37Â°C for 10 days. Yeasts were identified by morphologic criteria, germ tube test, chlamydospore formation test and assimilation test API 20 C AUX. Antifungal susceptibility was evaluated by disk agar diffusion method to amphotericin B, miconazole, ketoconazole, fluconazole, itraconazole and flucytosine (1 μg and 10 μg) and by broth macrodilution method for amphotericin B (inoculum 104 CFU/ml, YNB medium, incubation at 37Â°C, 24 h and 48 h). Results: All blood samples were positive and isolates identified as T. beigelii. All isolates had the same pattern of susceptibility in vitro. They were sensitive to miconazole, ketoconazole, fluconazole, itraconazole anf flucytosine, but resistant to amphotericin B. The resistance to amphotericin B was confirmed by broth macrodilution test with MIC = 12.8 μg/ml. Conclusion: We observed that the strain of T. beigelii was primary resistant to amphotericin B. Amphotericin B is the most important agent in therapy of disseminated fungal infections but most of T. beigelii strains are resistant to this antifungal. Therefore it is important to test susceptibility to antifungal agents in vitro for any isolate from blood samples, especially in immunocompromized patients.
Full conference title:
16th European Congress of Clinical Microbiology and Infectious Diseases
- ECCMID 16th (2006)