[1]Baraikio, D., [2]Daokoru-Olukole, C., and 3Abdu, A. B.
1Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmacy, Niger Delta University, Wilberforce-Island, Bayelsa State, Nigeria
2Department of Microbiology, Faculty of Science, Niger Delta University, Wilberforce-Island, Bayelsa State, Nigeria
3Department of Medical Microbiology and Parasitology, Faculty of Basic Clinical Sciences, Niger Delta University, Wilberforce-Island, Bayelsa State, Nigeria
*Correspondence to: simply4didi@yahoo.com; +2348035391089 Abstract:
Background: Candida species are normal flora of humans that can be pathogenic and cause candidiasis. Candidiasis is a public health problem due to its high prevalence, mortality, and increased costs of care associated with serious systemic Candida infections. This study was designed to identify the antifungal resistance pattern of Candida species isolated from different clinical specimens in Yenagoa, Bayelsa State, Nigeria, and to detect resistant genes associated with the Candida species.
Methodology: A total of 500 patients from 5 different health facilities in Yenagoa, Bayelsa State, Nigeria, with clinical features of urinary tract infection (candiduria), cutaneous candidiasis, oral thrush, lower respiratory tract infection and HIV/TB were selected in the study. Urine, skin, sputum and mouth samples were obtained from the patients and cultured on Sabouraud Dextrose agar and Brilliance Candida agar. The isolates were phenotypically identified using standard mycological methods and genotypically confirmed by polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) region of the rRNA genes and sequencing. The semi-solid agar antifungal susceptibility testing method was performed on the isolates against commonly used antimycotic agents. The known antifungal resistance gene Erg11 gene, was amplified by PCR.
Results: From clinical samples obtained from a total of 500 patients, 170 clinical isolates of Candida species were identified, giving the prevalence of Candida isolation of 34.0% in the study. Candida albicans was the predominant species (64.70%, n=110), followed by Pichia kudriavzevii (16.47%, n=28), Nakaseomyces glabratus (12.35%, n=21), Candida akabanensis (5.29%, n=9) and Candida tropicalis (1.17%, n=2). Female patients were more prone to Candida infection (36.6%, n=102/279) and age group 28-37 years (40.2%, n=41/102) had the highest prevalence of Candida species, but no statistically significant difference in Candida prevalence with respect to sex (p=0.2069) and age (p=0.1743). The three antimycotic agents to which Candida isolates exhibited the highest rates of resistance were griseofulvin (61.8%, n=105), ketoconazole (52.9%, n=90), and itraconazole (51.8%, n=88). Less than half of the isolates were resistant to fluconazole (n=70, 41.2%) and terbinafine (n=62, 36.5%). Nystatin had the lowest rates of resistance (19.4%, n=33). Erg II gene was detected in P. kudriavzevii, C. albicans, and C. tropicalis isolates.
Conclusion: Increased antifungal resistance by Candida species is a public health problem that can lead to failure in treatment, spread of infection and possibly death especially, in immune compromised individuals. Erg 11 genes contribute to Candida species resistance to antifungal drugs
Keywords: Candida, Normal flora, Antifungal agents, Anti-fungal resistance gene. PCR