Kodamaea ohmeri Isolates from Patients in a University Hospital: Identification, Antifungal Susceptibility, and Pulsed-Field Gel Electrophoresis Analysis

Abstract

Data on clinical isolates of Kodamaea (Pichia) ohmeri, an emerging fungal pathogen, are scarce. Over the past 5 years, we identified yeast isolates from nine patients with fungemia as K. ohmeri by using the API 20C system. Here, we reanalyzed these isolates first by sequencing the internal transcribed spacer 2 (ITS2) regions and then by growing the isolates on CHROMagar Candida medium and subjecting them to pulsed-field gel electrophoresis (PFGE). Based on their ITS2 sequences, six of the nine isolates were confirmed as K. ohmeri, while the others were identified as Candida haemulonii (n ‫؍‬ 2) and Candida parapsilosis (n ‫؍‬ 1). PFGE karyotyping of the K. ohmeri isolates revealed similar major bands, and their colonies showed a characteristic color change from pink to blue when grown on CHROMagar Candida medium for more than 48 h. For K. ohmeri, the ranges of MICs of fluconazole, voriconazole, caspofungin, and micafungin were 2 to 32 g/ml, 0.03 to 0.5 g/ml, 0.125 to 0.25 g/ml, and 0.03 to 0.06 g/ml, respectively. Restriction endonuclease analysis of genomic NotI-digested DNA (REAG-N) from isolates from different patients produced unique patterns, suggesting that the fungemia had occurred sporadically. This study determined that ITS2 sequence data, PFGE karyotypes, and CHROMagar Candida chromogenic culture medium are reliable diagnostic tools for identifying K. ohmeri while REAG-N is useful for genotyping the clinical isolates of K. ohmeri.

Genetic Diversity among Korean Candida albicans Bloodstream Isolates: Assessment by Multilocus Sequence Typing and Restriction Endonuclease Analysis of Genomic DNA by Use of BssHII

“…Banding patterns with Ն95% but less than 100% of the bands matching were termed "similar" and grouped into subtypes (subtype a, b, or c) of a given REAG-B type. Isolates with less than 95% of bands matching were considered different (10,18,21). All analyses were performed at least twice.…”

Oral colonization by yeasts in HIV-positive patients in Brazil

“…The most common non-albicans Candida species are C. glabrata, C. parapsilosis, C. tropicalis and C. krusei which have been frequently isolated from oral and systemic candidiasis. Other yeasts that are less common than Candida have been associated with life-threatening infections in immunocompromised hosts, such as Trichosporon, Rhodotorula, Non-neoformans Cryptococcus species, Geotrichum, Hansenula anomala 13 and Kodamaea ohmeri 17,37 .…”

“…membranaefaciens, is an environmental strain commonly used in the food industry. However, it is also an emerging fungal pathogen, particularly in immunocompromised patients 17 . In 2010, SHANG et al conducted a search of English medical literature from 1970 to 2008 and found 20 reported cases of K. ohmeri infection 37 .…”

Photodynamic inactivation of biofilms formed by Candida spp., Trichosporon mucoides, and Kodamaea ohmeri by cationic nanoemulsion of zinc 2,9,16,23-tetrakis(phenylthio)-29H, 31H-phthalocyanine (ZnPc)

“…It causes invasive opportunistic infections in immunocompromised hosts and is often associated with the presence of implanted devices. It also has developed resistance to azoles and a reduced susceptibility to caspofungin [16][17][18][19]. K. ohmeri has already been isolated from HIV-positive patients with pseudomembranous oral candidiasis and from diabetic and hemodialyzed users of dental prostheses [20,21].…”

“…membranaefaciens, is an extremely uncommon human pathogenic yeast [15]. K. ohmeri is an environmental strain commonly used in the food industry for the fermentation of pickles, rinds, and fruit [16]. It causes invasive opportunistic infections in immunocompromised hosts and is often associated with the presence of implanted devices.…”