Isolation of Candida africana in oral candidiasis: First report among cancer patients in Iran

Abstract

Background and Purpose: Oropharyngeal candidiasis (OPC) is a fungal infection of the oral cavity caused by the members of C. albicans complex. Although C. africana, as a part of the complex, is considered to be mostly responsible for the development of vulvovaginal candidiasis, it may be associated with a wider clinical spectrum.
 Case report: This report described two cases diagnosed with oral candidiasis during the receipt of treatment for malignancies. Conventional and molecular tests were performed on the samples collected from the patients’ oral cavities. The test results revealed C. africana as the causative agent of oral candidiasis. Furthermore, in vitro antifungal susceptibility test indicated the full susceptibility of all C. africana isolates to caspofungin. However, the data were also suggestive of the resistance against fluconazole and amphotericin B. Caspofungin was used as the main antifungal agent for the treatment of oral candidiasis, resulting in the improvement of thrush in patients. The resistance of C. africana to fluconazole and amphotericin B suggests the necessity of performing in vitro susceptibility testing on the isolates for the selection of appropriate antifungal agents.
 Conclusion: As the findings indicated, the achievement of knowledge regarding C. africana as an emerging non-albicans Candida species and its antifungal susceptibility profile is crucial to select antifungal prophylaxis and empirical therapy for oral candidiasis in cancer patients undergoing chemotherapy.

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

“…Regarding the susceptibility of vaginal C africana and C dubliniensis isolates to different antifungal drugs, previous studies showed that these yeasts are generally sensitive to several commonly used antimycotics 23,35,41 . However, there are some reports showing that C africana exhibits antifungal susceptibility patterns different from those of C albicans 23 and some isolates have been classified as resistant to itraconazole, fluconazole, voriconazole, clotrimazole, 5‐flucytosine and terbinafine 12,22,23,25 …”

“…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 .…”

“…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 . These epidemiological findings support the hypothesis that C africana prevalence, and/or drug resistance, can be geographically variable 23 and suggest further studies, in particular in vitro susceptibility testing of promising new drugs.…”

Oral Candidiasis in Hematological Malignancy Patients: Identification and Antifungal Susceptibility Patterns of Isolates

“…All the tests were carried out in duplicate. The MIC breakpoints were defined for each antifungal agent as follows: fluconazole (susceptible MIC ≤ 8 µg/mL; resistant MIC > 8 µg/mL), amphotericin B (susceptible MIC ≤ 1 µg/mL; resistant MIC > 1 µg/mL), and caspofungin (susceptible MIC ≤ 0.25 µg/mL; resistant MIC ≥ 1 µg/mL) (12).…”

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

“…However, some reports have shown that the antifungal susceptibility patterns of C. africana and C. dubliniensis are slightly different from those of C. albicans [5,6]. Moreover, based on previous studies, some C. africana isolates have been classified as resistant to itraconazole, fluconazole, voriconazole, clotrimazole, 5-flucytosine, and Terbinafine [4,7,8]. Echinocandins is the first-line antifungal drug for the treatment of Candida infections and has shown prolonged post antifungal effect and concentration-dependent killing activity against the majority of Candida species, including the C. albicans complex [9,10] polymerase chain reaction (PCR) amplification of the hyphal wall protein 1 (HWP1) gene [11].…”