Division of Medical Mycology, Teaching and Research Laboratory in Clinical Analyses, Department of Clinical Analysis of State University of Maringá, Paraná, Brazil.
Division of Medical Mycology, Teaching and Research Laboratory in Clinical Analyses, Department of Clinical Analysis of State University of Maringá, Paraná, Brazil.
Microb Pathog. 2017 Dec;113:225-232. doi: 10.1016/j.micpath.2017.10.044. Epub 2017 Oct 23.
Although the majority of Candida infections are thought to come from endogenous sources, the healthcare workers' (HCWs) hands are being increasingly reported as vehicles for the transmission of pathogens. The aim of the present study was to evaluate the susceptibility of yeast isolated from the HCWs' hands and ICU (Intensive Care Unit) surfaces to antifungal agents and to determine the virulence potential and the genetic similarity between the same.
The susceptibility of yeasts from the HCWs' hands (n = 57) and ICU surfaces (n = 98) to conventional antifungals (fluconazole, voriconazole, amphotericin B and micafungin) was evaluated using the broth microdilution assay accordance with CLSI M27-A3. Additionally, some virulence factors such as adhesion and biofilm capacity on abiotic surfaces and on endothelial cells were evaluated, as well as germ tube formation. The similarity among yeast isolates were evaluated by the RAPD technique using the P4, OPA18 and OPE18 primers.
Five species of Candida were found on the HCWs' hands (C. albicans, C. parapsilosis (sensu stricto), C. glabrata, C. tropicalis and C. krusei) and two on ICU surfaces (C. albicans and C. parapsilosis (sensu stricto)). The isolates from hands had higher resistance rates, with C. glabrata having the highest indices (100% FLU; 100% MFG). The similarity of C. albicans from HCWs and ICU surfaces was ≥80% according to the three primers analyzed. Candida spp. from hands had a greater potential for adhesion and biofilm formation on abiotic surfaces (p < 0.05). C. albicans from ICU surfaces had the greatest potential of adhesion on endothelial cells after 2 and 24 h, and presented high filamentation in SEM images and formed more and larger germ tubes (p < 0.05).
the present study showed the significant virulence potential of yeasts transmitted in the hospital environment for the first time. Additionally, healthy people working in the ICU can carry these yeasts, which are capable of surviving in hospital surfaces, on their hands, offering a risk to patients, especially those who are immunocompromised.
尽管大多数念珠菌感染被认为来自内源性来源，但医护人员的手越来越被认为是病原体传播的媒介。本研究的目的是评估从医护人员的手和 ICU（重症监护病房）表面分离出的酵母对抗真菌药物的敏感性，并确定它们之间的毒力潜力和遗传相似性。
使用肉汤微量稀释法按照 CLSI M27-A3 评估来自医护人员的手（n=57）和 ICU 表面（n=98）的酵母对常规抗真菌药物（氟康唑、伏立康唑、两性霉素 B 和米卡芬净）的敏感性。此外，还评估了一些毒力因子，如在非生物表面和内皮细胞上的粘附和生物膜形成能力，以及芽管形成。使用 P4、OPA18 和 OPE18 引物的 RAPD 技术评估酵母分离株之间的相似性。
在医护人员的手上发现了五种念珠菌（白色念珠菌、近平滑念珠菌（严格意义上的）、光滑念珠菌、热带念珠菌和克柔念珠菌）和两种在 ICU 表面（白色念珠菌和近平滑念珠菌（严格意义上的））。手上的分离物具有更高的耐药率，其中光滑念珠菌的指数最高（FLU 为 100%；MFG 为 100%）。根据分析的三个引物，医护人员手上的白色念珠菌的相似性≥80%。与非生物表面相比，手上的念珠菌具有更大的粘附和生物膜形成潜力（p<0.05）。在 2 和 24 小时后，来自 ICU 表面的白色念珠菌在内皮细胞上具有最大的粘附潜力，并在 SEM 图像中表现出高度丝状化，形成更多和更大的芽管（p<0.05）。
本研究首次显示了在医院环境中传播的酵母的显著毒力潜力。此外，在 ICU 工作的健康人可以携带这些在医院表面存活的酵母，这对患者构成了风险，特别是那些免疫功能低下的患者。
