在大自然中,念珠菌属是正常居民,可以在多种脊椎动物中观察到。在人类中,特别是对于那些成为机会性病原体牺牲品的癌症患者,这群易感多药耐药和形成生物膜的酵母,是最常见的。在这项研究中,从越南鼻咽癌患者的76个口腔病变样本中分离出念珠菌,使用CHROMagar™进行形态学鉴定,胚芽管形成,和衣原体孢子形成试验,并通过PCR-RFLP进行分子确认。然后测试了这些分离株的药物敏感性,并对基因ERG11进行了DNA测序,以研究其耐药机制。结果表明,白色念珠菌仍然是最流行的物种(占病例的63.16%),其次是光滑念珠菌,热带念珠菌,还有Krusei念珠菌.非白色念珠菌对试验药物的耐药率为85.71%,53.57%,和57.14%的氟康唑,克霉唑,和咪康唑,分别。尽管白色念珠菌的耐药率低于非白色念珠菌,比预期的要高,表明了一种新出现的耐药现象。此外,ERG11DNA测序显示不同的突变(尤其是K128T),暗示存在多种抵抗机制。总之,结果表明,越南癌症患者中念珠菌属的耐药情况令人担忧,并强调了在治疗前进行念珠菌属鉴定及其药物敏感性的重要性.
In the nature, Candida species are normal inhabitants and can be observed in a wide variety of vertebrates. In humans, especially for cancer patients who fall prey to opportunistic pathogens, this group of susceptible multi-drug resistant and biofilm-forming yeasts, are among the commonest ones. In this study, Candida species in 76 oral lesion samples from Vietnamese nasopharyngeal-cancer patients were isolated, morphologically identified using CHROMagar™, germ tube formation, and chlamydospore formation tests, and molecularly confirmed by PCR-RFLP. The drug susceptibility of these isolates was then tested, and the gene
ERG11 was DNA sequenced to investigate the mechanism of resistance. The results showed that Candida albicans remained the most prevalent species (63.16% of the cases), followed by Candida glabrata, Candida tropicalis, and Candida krusei. The rates of resistance of non-albicans Candida for tested drugs were 85.71%, 53.57%, and 57.14% to fluconazole, clotrimazole, and miconazole, respectively. Although the drug-resistance rate of Candida albicans was lower than that of non-albicans Candida, it was higher than expected, suggesting an emerging drug-resistance phenomenon. Furthermore,
ERG11 DNA sequencing revealed different mutations (especially K128T), implying the presence of multiple resistance mechanisms. Altogether, the results indicate an alarming drug-resistance situation in Candida species in Vietnamese cancer patients and emphasize the importance of species identification and their drug susceptibility prior to treatment.