Molecular Identification, Genotypic Diversity, Antifungal Susceptibility, and Clinical Outcomes of Infections Caused by Clinically Underrated Yeasts, Candida orthopsilosis, and Candida metapsilosis: An Iranian Multicenter Study (2014–2019)

Abstract

Despite the increasing occurrence of Candida orthopsilosis and Candida metapsilosis in clinical settings, little is known about their microbiological and clinical properties. Herein, we conducted a national retrospective study (2014–2019) from multiple centers in Iran. Among the 1,770 Candida isolates collected, we identified 600 Candida parapsilosis species complex isolates. Isolate identification was performed by 9-plex PCR, matrix-assisted laser desorption-time of flight mass spectrometry (MALDI-TOF MS), and rDNA sequencing, and antifungal susceptibility testing (AFST) followed CLSI M27-A3/S4; genotyping was performed by amplified fragment length polymorphism (AFLP) analysis; and clinical information was mined. Thirty-one isolates of C. orthopsilosis from various clinical sources, one mixed sample (blood) concurrently containing C. orthopsilosis and C. parapsilosis and one isolate of C. metapsilosis from a nail sample were identified. Although both 9-plex PCR and MALDI-TOF successfully identified all isolates, only 9-plex PCR could identify the agents in a mixed sample. For the C. orthopsilosis isolates, resistance (non-wild type) was noted only for itraconazole ( n = 4; 12.5%). Anidulafungin and fluconazole showed the highest and voriconazole had the lowest geometric mean values. AFLP analysis showed three main and four minor genotypes. Interestingly, 90% of nail isolates clustered with 80% of the blood isolates within two clusters, and four blood isolates recovered from four patients admitted to a hospital clustered into two genotypes and showed a high degree of similarity (>99.2%), which suggests that C. orthopsilosis disseminates horizontally. Supported by our data and published case studies, C. orthopsilosis and C. metapsilosis can be linked to challenging clinical failures, and successful outcomes are not always mirrored by in vitro susceptibility. Accordingly, conducting nationwide studies may provide more comprehensive data, which is required for a better prognosis and clinical management of patients.

Evaluation of Molecular Epidemiology, Clinical Characteristics, Antifungal Susceptibility Profiles, and Molecular Mechanisms of Antifungal Resistance of Iranian Candida parapsilosis Species Complex Blood Isolates

“…C. orthopsilosis isolates were recovered from all centers involved (n = 4) and varied in AFLP fingerprint profiles and showed a higher degree of heterogeneity that could be due to the hybrid nature of this species (Pryszcz et al, 2014). Positivity of one blood samples for both C. parapsilosis and C. orthopsilosis was extensively discussed in our previous study (Arastehfar et al, 2019a) and confirmed earlier findings (Barbedo et al, 2015) that almost 9.5% of blood isolates contained both species.…”

“…In order to check the genotypic diversity, a previously described AFLP fingerprinting method was used (Arastehfar et al, 2019a). Diluted PCR products were analyzed by capillary electrophoresis on an ABI 3730xL Genetic Analyzer (ThermoFisher Scientific, Waltham, MA, USA) and the obtained data were analyzed by Bionumerics software v7.6.2 (Applied Math, Sint-Martens-Latem, Belgium).…”

Candida tropicalis is the most prevalent yeast species causing candidemia in Algeria: the urgent need for antifungal stewardship and infection control measures

“…Of note, genotypic variation weas observed for multiple FLZS isolates recovered from the same patient in this study; therefore, genotypic variation may not always be accompanied by resistance development. Interestingly, the isolate of C. orthopsilosis from the hands of a HCW may reinforce the hypothesis that, similar to C. parapsilosis, it may have been transferred from the hands of HCWs [40]. Moreover, isolation of A. melanogenum, N. albida, and N. liquefaciens from high touch areas, which are reported to have elevated MIC values to various antifungals [41][42][43] and finding Aureobasidium melanogenum in both blood and the environment are worrisome.…”

Low in vitro activity of sertaconazole against clinical isolates of dermatophyte

“…These differences between the observed susceptibility in the studied isolates may be due to different geographical locations and climatic conditions. In this regard, environmental conditions can affect the expression of certain genes and production of specific enzymes in fungi [29]. Furthermore, the number of isolates and diversity of the studied species can fundamentally influence the results.…”