<em>Candida africana</em> and <em>Candida dubliniensis</em> as causes of pediatric candiduria: A study using <em>HWP1</em> gene size polymorphism

Abstract

Background Candida species cause a wide spectrum of disease entities. Candida africana and Candida dubliniensis –members of Candida albicans complex-are currently gaining both clinical and epidemiologic significance. Materials and methods Totally, 150 pediatric isolates that had previously been identified as C. albicans species complex based on a positive germ tube test were included. The isolates were cultured on CHROMagar Candida medium to ensure their purity and the results of germ tube test. For definitive speciation, PCR amplification and size polymorphism of the hyphal wall protein 1 ( HWP1 ) gene was used. The results of HWP1 -PCR were confirmed by sequencing the amplified fragments for randomly selected isolates of C. africana and C. dubliniensis . Results All 150 isolates included in this study were reconfirmed as C. albicans complex on chromogenic media. Based on the HWP1 gene size polymorphism, 141 (94%) isolates were identified as C. albicans , 2 (1.33%) as C. africana , and 1 (0.67%) as C. dubliniensis . The remaining 6 (4%) C. albicans complex isolates were a mix of C. albicans and C. africana . All isolates of C. africana and C. dubliniensis have been recovered from cases of candiduria. Conclusion C. africana , either alone or mixed with C. albicans , could be a cause of candiduria among pediatric patients and should not be ignored.

Differentiation of Candida albicans complex species isolated from invasive and non-invasive infections using HWP1 gene size polymorphism

“…C. albicans , C. dubliniensis , and C. africana [ 7 ]. In the present study, C. albicans (94.89%) was the predominant species among the 235 isolates, which is in line with the results of some previous studies [ 12 , 16 , 21 - 24 ]. In the present research, the majority (97.3 %) of C. albicans with 941 bp DNA fragments were homozygous, while 2.97% (n=7) of them produced two DNA fragments of 850 and 941 bp, demonstrating heterozygosity at HWP1 locus.…”

“…In this study, C. africana (3.4%) had a higher prevalence rate than C. dubliniensis (1.7%). This result corroborates those of the previous research performed in Iran [ 7 , 12 , 26 - 28 ]. However, the higher isolation rate of C. dubliniensis over C. africana has also been reported in other studies [ 21 , 29 , 30 ].…”

“…Although epidemiological and clinical data suggest that C. africana has a worldwide distribution, little is known about the frequency of Candida isolated from systemic candidiasis in Iran [ 12 ]. Hence, this study was carried out to investigate the microbial epidemiology of C. albicans complex species among different clinical specimens, especially those strains isolated from systemic candidiasis.…”

Vulvovaginal candidiasis: An overview of mycological, clinical, and immunological aspects

“…These culture media have the same limitation as corn meal agar and could not differentiate C. dubliniensis and C. africana from C. albicans 47–49 . Similarly, although germ tube test can discriminate between C. albicans and NAC species, it has similar results for C. albicans , C. dubliniensis , and C. africana 49,50 . As a solution for these limitations, molecular techniques have been used as complement to conventional methods that provide accurate outputs in a short time (1.5–3 h) 51 .…”

Molecular identification and antifungal susceptibility profiles of Candida dubliniensis and Candida africana isolated from vulvovaginal candidiasis: A single‐centre experience in Iran

“…Recent studies have shown that most of vaginal C africana isolates from Iran exhibit resistance to various antifungal drugs, 21,22 and ~28% of world isolates appear to be resistant to itraconazole 23 . Furthermore, although C africana is generally associated with vaginal infections, in Iran, this pathogen has also been reported as a cause of paediatric candiduria, 24 and/or oropharyngeal candidiasis in cancer patients 25 . From these latter patients, fluconazole‐ and amphotericin B‐resistant isolates have been also recovered 25 .…”