Pramodhini Subramanian, Srirangaraj Sreenivasan, Easow Joshy Maducolil
Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth (deemed to be university), Puducherry, India.
J Lab Physicians. 2021 Sep;13(3):231-237. doi: 10.1055/s-0041-1730880. Epub 2021 Jun 28.
The increased incidence of candiduria in hospitalized patients is due to the use of indwelling devices, long-term antibiotics, parenteral nutrition, and immunocompromised status of the patient. In this study, an attempt was made to speciate, characterize, and determine the antifungal susceptibility pattern of isolated from urinary tract infections (UTIs). A total of 70 isolates were obtained from urine samples. The isolated species were studied for the production of virulence factors like phospholipase, protease activities, hemolysin, and biofilm production. Antifungal susceptibility testing of the isolated yeasts was done using Mueller-Hinton agar supplemented with 0.5 mg/mL methylene blue by E-test method for amphotericin B, fluconazole, caspofungin, and voriconazole. Out of 70 isolates, was the most frequently isolated species (65.7%), followed by (14.3%), (7.1%), (5.7%), (4.3%), and (2.9%). A total of 37.1% were biofilm producers, 62.9% showed proteinase activity, 38.6% were phospholipase positive, and 58.6% isolates showed hemolytic activity. Antifungal susceptibility profile of species showed 38.6, 25.7, 15.7, and 12.9% resistance to amphotericin B, fluconazole, caspofungin, and voriconazole, respectively. A rising trend in isolation of non-albicans from urinary isolates was noticed, which was statistically significant when comparing catheterized and noncatheterized urinary isolates from our study. However, there was no statistically significant difference when different virulence factor expressions were compared among spp. isolated from catheterized and noncatheterized urinary samples. Due to this rise in non-albicans species causing UTI that are intrinsically resistant to certain antifungal agents like azoles and increasing incidence of antifungal resistance, it is essential to monitor the antifungal susceptibility profile of species causing candiduria.
住院患者念珠菌尿症发病率增加是由于使用留置装置、长期使用抗生素、肠外营养以及患者免疫功能低下。在本研究中，尝试对从尿路感染（UTIs）中分离出的念珠菌进行分类、鉴定并确定其抗真菌药敏模式。共从尿液样本中获得70株分离株。对分离出的菌种进行了毒力因子产生情况的研究，如磷脂酶、蛋白酶活性、溶血素和生物膜形成。采用补充有0.5mg/mL亚甲蓝的Mueller-Hinton琼脂，通过E-test法对两性霉素B、氟康唑、卡泊芬净和伏立康唑进行分离酵母的抗真菌药敏试验。在70株分离株中，白色念珠菌是最常分离出的菌种（65.7%），其次是热带念珠菌（14.3%）、光滑念珠菌（7.1%）、近平滑念珠菌（5.7%）、克柔念珠菌（4.3%）和季也蒙念珠菌（2.9%）。共有37.1%的菌株产生生物膜，62.9%表现出蛋白酶活性，38.6%磷脂酶呈阳性，58.6%的分离株表现出溶血活性。白色念珠菌的抗真菌药敏谱显示，对两性霉素B、氟康唑、卡泊芬净和伏立康唑的耐药率分别为38.6%、25.7%、15.7%和12.9%。注意到从尿液分离株中分离出的非白色念珠菌呈上升趋势，在比较本研究中导尿和非导尿尿液分离株时具有统计学意义。然而，在比较从导尿和非导尿尿液样本中分离出的念珠菌属菌种的不同毒力因子表达时，没有统计学显著差异。由于导致UTI的非白色念珠菌菌种对某些抗真菌药物（如唑类）具有固有耐药性且抗真菌耐药性发病率不断增加，监测引起念珠菌尿症的念珠菌菌种的抗真菌药敏谱至关重要。
