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).

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.

A chronic disseminated dermatophytosis due to Trichophyton violaceum.

A 48-year-old female had presented dandruff and breakable hair for more than 40 years, dry scaly erythema on bilateral palms and feet accompanying with nail destruction for 20 years, and scaling papules on the buttock for 5 years. Direct microscopic examination showed endothrix anthroconidia within broken hair and septate and branched hyphae within skin and nail lesion. Fungal cultures from all infected sites were examined by morphology, ITS sequencing, and random amplified polymorphic DNA fingerprinting, and were identified as Trichophyton violaceum from the same source. The patient was treated with oral terbinafine 0.25 g/day as well as with 1% terbinafine gel for external use and with 2% ketoconazole lotion for shampoo and bath. A follow-up after 4 weeks showed that the lesions decreased significantly.

Molecular characterization and in vitro antifungal susceptibility of 80 clinical isolates of mucormycetes in Delhi, India.

Mucormycosis is a highly aggressive disease which is usually fatal in immunocompromised patients. The species of mucormycetes show significant differences in susceptibility to amphotericin B, azoles and terbinafine. The precise species level identification for this fungal group could be achieved by internal transcribed-spacer (ITS) region sequencing. Herein, we present the largest series of antifungal susceptibility data of molecularly characterised isolates of mucormycetes reported so far from India. Eighty isolates originating from 71 patients comprised 50 (62.5%) from pulmonary cases, 15 (19%) from rhino-orbital-cerebral, 13 (16.2%) from cutaneous and 2 (2.5%) from disseminated mucormycosis. ITS and D1/D2 regions sequencing of the isolates identified, Rhizopus arrhizus var. delemar (n = 25), R. arrhizus var. arrhizus (n = 15), R. microsporus (n = 17), R. stolonifer (n = 3), Syncephalastrum racemosum (n = 11), Apophysomyces elegans (n = 2), A. variabilis (n = 2), Lichtheimia ramosa (n = 3) and Mucor circinelloides f. lusitanicus (n = 2). Amplified fragment length polymorphism analysis was done to genotype Rhizopus isolates and revealed 5 clusters of R. arrhizus, which were well separated from R. microsporus. Amphotericin B was the most potent antifungal followed by posaconazole, itraconazole and isavuconazole. Etest and CLSI MICs of amphotericin B showed 87% agreement. Overall, the commonest underlying condition was uncontrolled diabetes mellitus. Records of 54 patients revealed fatalities in 28 cases.

Recurrent arthritis by Candida glabrata, a diagnostic and therapeutic challenge.

Infectious arthritis due to Candida glabrata is very rare. A 40-year-old Iranian man had developed a painful swelling on the left knee since a year ago. A surgery (meniscectomy) was performed on his knee. However, in follow-up visit after 2 months, the patient's condition was deteriorated. Direct examination of synovial fluid with Gram and hematoxylin-eosin stains were negative for any bacterial or fungal infection or crystal elements; however, inoculation into BACTEC™ Mycosis IC/F and Plus Aerobic/F culture bottles led to the isolation of a yeast strain. The macroscopic examination on CHROMagar™ Candida medium combined with microscopical examination on CMT80 agar made a presumptive identification of the isolate to be considered as C. glabrata, and it was later on confirmed by ITS sequencing. Initial empirical treatment was started with intravenous amphotericin B for 4 weeks followed by oral itraconazole which was unsuccessful. Prescription of an oral 150-mg tablet of fluconazole was considered for a 2-month course. All symptoms completely declined, and no recurrence of infection was detected. Antifungal susceptibility testing (AFST) was performed for this isolate, and the result showed sensitivity to both amphotericin B and itraconazole and less susceptibility to fluconazole while clinical recovery was achieved by fluconazole. In any suspected clinical case caused by infectious agents, application of an effective fungal diagnostic test should be considered to avoid complications due to misdiagnosis. The correlation of AFST result with real in vivo therapeutic responses can be strain or patient dependent, and this should be considered for a successive treatment.