Center for Research in Medical Mycology (CIMM), Health Sciences Center (CCS), Federal University of Espírito Santo (UFES), Vitória, Espírito Santo, Brazil.
Infectious Diseases Postgraduate Program, Health Sciences Center (CCS), Federal University of Espírito Santo (UFES), Vitória, Espírito Santo, Brazil.
Mycoses. 2024 Aug;67(8):e13786. doi: 10.1111/myc.13786.
Candida spp. is an opportunistic pathogen that causes superficial and invasive infections with nosocomial outbreaks without strict hygiene protocols. Herein, we assessed oral colonisation by Candida spp. in 209 Intensive Care Unit (ICU) patients between July 2021 and April 2022, conducting clinical, epidemiological, and microbiological characterisation of those developing oral or invasive candidiasis.
Initial oral swabs were collected within 24 h of admission in the ICU, followed by collections on Days 2, 4, 6 and 8. Swabs from denture-wearing patients, abiotic surfaces, healthcare professionals' hands, and retroauricular regions were also obtained. Recovered yeasts and filamentous fungi were identified using MALDI-TOF MS and morphological characteristics, respectively. Genetic similarity of Candida spp. isolates was evaluated using Amplified fragment length polymorphism (AFLP), and the antifungal susceptibility profile was determined by broth microdilution.
In the study, 64.11% of patients were orally colonised by Candida spp. Of these, 80.59% were colonised within the first 24 h. Oral colonisation also occurred on subsequent days: 50%/Day 2, 26.92%/Day 4, and 11.53%/Days 6 and 8. Of the patients, 8.61% had oral candidiasis, mainly pseudomembranous. Among orally colonised patients, 2.23% developed invasive candidiasis. Besides, 89.47% of healthcare professionals evaluated were colonised. MALDI-TOF MS identified different yeast species, and C. albicans (45.34%), C. tropicalis (15.7%), and C. parapsilosis sensu stricto (9.88%) were the most prevalent. AFLP analysis indicated a high genetic correlation (≥97%) between C. parapsilosis sensu stricto isolates from patients and professionals. Three resistant C. albicans isolates were also found.
This study reported a diversity of yeast and filamentous fungi species in ICU patients and highlighted early Candida spp. colonisation risks for invasive candidiasis, as well as the potential horizontal transmission in the nosocomial setting, emphasising the need for effective infection control measures.
假丝酵母菌属是一种机会致病菌，在没有严格卫生规范的情况下会引起医院感染的浅表和侵袭性感染。在此，我们评估了 209 例重症监护病房（ICU）患者的口腔定植情况，这些患者于 2021 年 7 月至 2022 年 4 月间入院，对发生口腔或侵袭性念珠菌病的患者进行临床、流行病学和微生物学特征分析。
在 ICU 入住后 24 小时内采集初始口腔拭子，然后在第 2、4、6 和 8 天采集。还从戴假牙的患者、无生命的表面、医护人员的手和耳后区域采集拭子。使用 MALDI-TOF MS 和形态特征分别鉴定回收的酵母和丝状真菌。使用扩增片段长度多态性（AFLP）评估假丝酵母菌属分离株的遗传相似性，并通过肉汤微量稀释法确定抗真菌药敏谱。
在这项研究中，64.11%的患者口腔定植了假丝酵母菌属。其中，80.59%在入住后 24 小时内定植。随后的几天也发生了口腔定植：第 2 天 50%/天，第 4 天 26.92%/天，第 6 和 8 天 11.53%/天。8.61%的患者发生口腔念珠菌病，主要为假膜性。在口腔定植的患者中，2.23%发生侵袭性念珠菌病。此外，89.47%评估的医护人员也定植了。MALDI-TOF MS 鉴定出不同的酵母种，其中白假丝酵母菌（45.34%）、热带假丝酵母菌（15.7%）和近平滑假丝酵母菌（9.88%）最为常见。AFLP 分析表明，患者和医护人员中分离的近平滑假丝酵母菌严格意义上的亲缘关系很高（≥97%）。还发现了 3 株耐药白假丝酵母菌。
本研究报告了 ICU 患者中酵母和丝状真菌的多样性，并强调了侵袭性念珠菌病的早期假丝酵母菌属定植风险，以及医院环境中的潜在水平传播，强调了需要采取有效的感染控制措施。
