奥默毕赤酵母菌致早产儿医院获得性败血症的临床特点及同源性分析

Clinical features and homological analysis of Pichia ohmeri-caused hospital-acquired fungemia inpremature infants

目的分析早产儿医院获得性奥默毕赤酵母菌败血症的临床及分子生物学特点，以提高对该病的认识和治疗水平。方法回顾性分析2010年7至11月温州医学院附属育英儿童医院新生儿重症监护病房（NICU）6例奥默毕赤酵母菌败血症患儿的临床和病原学资料；对分离株进行鉴定，用随机引物多态性分析（RAPD）进行同源性分析；同时根据医院感染流行病学特征，对患儿周围环境和物品进行采样分析。结果6例患儿分离出奥默毕赤酵母菌前平均住院时间28d；使用抗菌药物时间为13—45d；6例患儿均接受静脉营养，其中4例接受机械通气，5例接受中心静脉置管。5例经卡泊芬净治疗15～30d后痊愈，1例使用氟康唑30d后痊愈。菌株经仪器鉴定和18SrDNA序列测定确认为奥默毕赤酵母菌。RAPD分型结果显示分离株均为同一克隆。采集的15份环境和物品标本培养结果均为阴性，但采取积极的医院感染控制措施后至2012年8月未再出现类似病例。结论奥默毕赤酵母菌引起的早产儿医院获得性败血症可在医院内传播，落实院内感染防控措施是关键；卡泊芬净治疗早产儿真菌血症是安全有效的。

Objective To analyze the clinical features of fungemia caused by Pichia ohmeri （P. ohmeri） in neonate intensive care unit and explore its molecular biological characteristics so as to improve its diagnosis and treatment level. Methods The clinical data of 6 infected infants were retrospectively analyzed. The strains obtained from them were identified and homologieal analysis was performed through randomly amplified polymorphic assay to explore the epidemiological characteristics of this nosocomial infection. Results Before the isolation of P. ohmeri, they received intravenous antibacterial therapy for 13--45 days. Among them, 4 received mechanical ventilation and 5 had a peripheral insertion of central venous catheters. Five infants were healed after a therapy of caspofungin for 15--30 days. One neonate recurred after a 30-day administration of fluconazole. The strain was identified and confirmed as P. ohmeri. RAPD genotyping results showed that all 6 strains were from the same clone. No similar cases occurred after positive control measures despite a negative epidemiological sampling. Conclusions P. ohmeri may cause premature infant fungemia and lead to its spread in hospital. Hospital infection control is a key point. And caspofungin is both safe and effective in the therapy of neonate fungemia.