Abstract:

Objective To explore the isolation, culture and drug sensitivety test of Stephanoascus ciferrii, so as to provide the correct basis for clinical diagnosis and treatment. Methods Two strains of Stephanoascus ciferrii from one patient with chronic suppurative otitis media and another patient with secondary biliary tract infection after liver transplantation were isolated and cultured by conventional methods. The colony characteristics and morphology of the fungi were observed. Vitek 2 Compact automatic microbiological analysis system was used for biochemical identification, and molecular identification was carried out in combination with ITS region sequencing. ATB FUNGUS 3 was used for drug sensitivity test. Results The isolates could grow on the common culture medium of the blood plate, CHROMagar and sabourauad plate. The colony was not easy to be scraped from the agar. With the extension of culture time, the colony color gradually became blue, the colony began to be rough and the center was obviously hollow. The spores and mycelium were observed under microscopy. The fungal spores were ovate and arranged along the mycelium. The isolates were identified by Vitek 2 Compact as the Stephanoascus ciferrii, and finally being comfirmed by molecular biological methods (similar to 100%). The results showed that both strains were sensitive to 5-fluorocytosine, amphotericin B, fluconazole, itraconazole and voriconazole. Conclusion Stephanoascus ciferrii is a rare opportunistic pathogenic fungus. Clinical laboratory traditional culture method combined with new molecular biology techniques, might quickly provide the accurate basis for clinical medication.

Key words: Stephanoascus ciferrii, fungal infection, separation and identification, sequence analysis