Molecular and antifungal susceptibility study on trichosporonemia and emergence of Trichosporon mycotoxinivorans as a bloodstream pathogen.
A total of 21 Trichosporon spp. isolates from blood over a period of 5 years (January 2009 to December 2013) were included in the study. The most common underlying diseases found were pancreatitis (33.3%) and cancer (33.3%). Trichosporon asahii (80.9%) was the commonest species followed by Trichosporon mycotoxinivorans (14.2%) and Trichosporon faecale (4.7%). On IGS1 region sequencing the most predominant T. asahii type in our region was genotype 1 (16/17 isolates; 94.1%) and one isolate belonged to genotype 4. Following the interpretative breakpoints for Candida albicans according to CLSI guidelines amphotericin B minimum inhibitory concentrations (MICs) were ≤1 μg/ml for 38% of isolates. Fluconazole MICs were ≤4 μg/ml for 33.3% of the isolates. Itraconazole MICs were ≤0.5 μg/ml for 52.3% of the isolates. However, the MICs to posaconazole and voriconazole were ≤0.5 μg/ml for all the isolates. The MICs to caspofungin and micafungin were ≤0.5 μg/ml for only 0.09% of the isolates. This study reemphasizes that IGS1 sequencing is the most reliable technique for accurate identification of Trichosporon spp. and also to identify the newer species like T. mycotoxinivorans, which still remains rare. Surveillance of antifungal susceptibility patterns can provide the local drug resistance data to the clinicians which can further aid better management of patients.
Department of Microbiology, All India Institute of Medical Sciences, New Delhi-110029, India.
Yubhisha
Y
Dabas
Department of Microbiology, All India Institute of Medical Sciences, New Delhi-110029, India.
Immaculata
I
Xess
Department of Microbiology, All India Institute of Medical Sciences, New Delhi-110029, India.
Pratibha
P
Kale
D000293:Adolescent; D000328:Adult; D000368:Aged; D000935:Antifungal Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D004271:DNA, Fungal / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005260:Female; D016469:Fungemia / Q000188:drug therapy / Q000382:microbiology*; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D016533:Mycological Typing Techniques; D010802:Phylogeny; D014250:Trichosporon / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D060586:Trichosporonosis / Q000188:drug therapy / Q000382:microbiology*; D055815:Young Adult
D000935:Antifungal Agents; D004271:DNA, Fungal; D004275:DNA, Ribosomal
Bloodstream infection; DNA sequencing; India; Trichosporon; antifungal susceptibility