An alarming rise of non-albicans Candida species and uncommon yeasts in the clinical samples; a combination of various molecular techniques for identification of etiologic agents

Abstract

Objective: Yeasts are unicellular microorganisms may cause systemic infection in immunocompromised patients. The aim of this study was to identify yeast strains isolated from clinical specimens using molecular techniques.Results: A total of 202 yeast strains isolated from 341 clinical samples between February 2017 and May 2019. All clinical isolates were identified using phenotypic and molecular tests including PCR-RFLP, duplex-PCR, multiplex-PCR, and PCR-sequencing. The most yeast fungal isolates were obtained from urine (66.8%), nail (9.4%), skin lesion (7.9%), bronchoalveolar lavage (5.9%), and blood (3.9%).One hundred and twenty-one Candida species were identified as non-albicans versus 76 Candida albicans. Trichosporon asahii, and Pichia terricola were uncommon non-Candida yeasts isolated from urine samples. For the first time, we isolated P. terricola as etiological agent of urinary tract infection in a pregnant female. Since Candida species show different levels of resistance to antifungal agents, precise identification of clinical isolates is critical for better treatment of infection.

Effect of initial antifungal therapy on mortality among patients with bloodstream infections with different Candida species and resistance to antifungal agents: A multicentre observational study by the Turkish Fungal Infections Study Group

“…Candida albicans remains the most frequently isolated species in almost every centre globally, however some studies report an increasing rate of isolation of non-albicans Candida spp. [9] . In a single-centre study from France, the change in species distribution of candidaemia isolates over a decade was evaluated and no significant differences was found between 20 0 0 and 2010 [10] .…”

Prevalence and Antifungal Susceptibility of Pathogenic Yeasts in China: A 10-Year Retrospective Study in a Teaching Hospital

“…Invasive candidiasis is a growing concern worldwide with high morbidity and mortality; it affects patients of all ages, including patients with malignancies, HIV-negative immunocompromised (IC) patients, and non-immunocompromised (NIC) patients among those who are critically ill, often admitted to an intensive care unit (ICU), or diagnosed with diabetes mellitus or uncontrolled hyperglycemia requiring invasive mechanical ventilation ( Berdal et al, 2014 ; Bitar et al, 2014 ; Epelbaum and Chasan, 2017 ; Alves et al, 2018 ; Ding et al, 2018 ; Mantadakis et al, 2018 ). Although Candida albicans is still the leading cause of fungemia, epidemiological switch and species distribution have shifted toward non- C. albicans in recent decades, especially in patients with severe health conditions ( Canton et al, 2012 ; Pfaller et al, 2015 ; Taei et al, 2019 ; Xiao et al, 2020 ). There are considerable geographic and population variability in the prevalence of pathogenic Candida species; for example, Candida tropicalis is frequently isolated in Asia and South America, and Candida glabrata has a high frequency in North and Central Europe and the United States, specially among elderly people ( Castanheira et al, 2016 ; Pappas et al, 2018 ).…”

Biofilm formation by Candida albicans and Candida glabrata isolated from urine specimens of diabetic Iraqi women

“…In recent years, we noted that non-albicans Candida species prevalence was more than C. albicans. Epidemiological data revealed that non-albicans Candidia infections are rising globally (Taei et al, 2019). Many studies have suggested that the distribution of Candida species that cause candiduria varies regionally (Toner et al, 2016).…”