Department of Microbiology, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Hnevotinska 3, 77515, Olomouc, Czech Republic.
Folia Microbiol (Praha). 2011 Sep;56(5):407-14. doi: 10.1007/s12223-011-0063-8. Epub 2011 Sep 6.
A case report of ventriculoperitoneal shunt infection caused by Candida lusitaniae in a 6-year-old patient with cerebral astrocytoma and obstructive hydrocephalus is presented briefly with emphasis on the course of antifungal treatment. Seven isolates recovered subsequently from the cerebrospinal fluid were studied retrospectively. To confirm identity, isolates were typed using pulsed-field gel electrophoresis and melting curve of random amplified polymorphic DNA (McRAPD). Further, the ability to form biofilm and its susceptibility to systemic antifungals were evaluated. Using McRAPD, identity of C. lusitaniae isolates showing slight microevolutionary changes in karyotypes was undoubtedly confirmed; successful application of numerical interpretation of McRAPD for typing is demonstrated here for the first time. The strain was also recognized as a strong biofilm producer. Moreover, minimum biofilm inhibitory concentrations were very high, in contrast to low antifungal minimum inhibitory concentrations of isolates. It can be concluded that McRAPD seems to be a simple and reliable method not only for identification but also for typing of yeasts. A ventriculoperitoneal shunt colonized by C. lusitaniae was revealed as the source of this nosocomial infection, and the ability of the strain to form biofilm on its surface likely caused treatment failure.
简要报道了一例 6 岁脑星形细胞瘤伴梗阻性脑积水患儿因感染葡萄牙假丝酵母菌导致脑室-腹腔分流感染的病例，重点介绍了抗真菌治疗过程。随后从脑脊液中分离出 7 株病原菌进行回顾性研究。为了确认鉴定结果，采用脉冲场凝胶电泳和随机扩增多态性 DNA 熔解曲线（McRAPD）对分离株进行分型。此外，还评估了其形成生物膜的能力及其对系统用抗真菌药物的敏感性。使用 McRAPD 技术，对表现出轻微染色体组微进化改变的葡萄牙假丝酵母菌分离株的鉴定结果得到了明确证实；本文首次成功应用 McRAPD 的数值解释进行了分型。该菌株还被鉴定为一种强生物膜产生菌。此外，最低生物膜抑制浓度非常高，而分离株的最低抗真菌抑制浓度则较低。可以得出结论，McRAPD 似乎不仅是一种简单可靠的鉴定方法，也是一种鉴定酵母的方法。该医院感染的来源是被葡萄牙假丝酵母菌定植的脑室-腹腔分流，而该菌株在其表面形成生物膜的能力可能导致了治疗失败。
