Diekema D J, Messer S A, Hollis R J, Wenzel R P, Pfaller M A
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242, USA.
Diagn Microbiol Infect Dis. 1997 Nov;29(3):147-53. doi: 10.1016/s0732-8893(97)81804-4.
Candida parapsilosis, an important nosocomial pathogen and the most common species of Candida found on the hands of health care workers, is a rare cause of prosthetic valve endocarditis (PVE). From March through June 1994, four cases of C. parapsilosis PVE were diagnosed at a 400-bed community hospital. The mean time to presentation after valve replacement surgery was 148 days (range, 20 to 345). Three of the four patients died of complications of PVE. Multiple environmental cultures were performed, and only one was positive for C. parapsilosis. Cultures from the bypass pump, cell saver, cardioplegia solution, and subsequent valves were all negative. All valve replacements were performed by the same operating room team. Interviews with the surgeon and physician assistant, the only personnel involved in all cases, revealed that their hypoallergenic gloves were subject to frequent tears during valve replacement procedures, often requiring several glove changes per procedure. Hand cultures of personnel were obtained, and cultures from 20 individuals (26%) were positive for C. parapsilosis. Hand cultures of the surgeon and physician assistant obtained 8 months after the last case had surgery were negative for yeasts. Molecular typing of the 3 available case isolates, 14 epidemiologically unrelated patient isolates, 1 environmental isolate, and 20 hand isolates was performed by electrophoretic karyotyping and restriction endonuclease analysis of genomic DNA using restriction enzymes BssHII and EagI followed by pulsed field gel electrophoresis. The three case isolates were identical by restriction endonuclease analysis of genomic DNA, and two of the three shared the same electrophoretic karyotyping profile. The remaining patient, environmental, and hand isolates represented 29 different DNA types and were distinctly different from the case isolates. All of the isolates tested were susceptible to amphotericin B, 5FC, fluconazole, and itraconazole. The circumstantial evidence suggests the probability of glove tears during valve replacement surgery and subsequent transmission of C. parapsilosis to patients.
近平滑念珠菌是一种重要的医院病原体，也是在医护人员手上发现的最常见的念珠菌种类，是人工瓣膜心内膜炎（PVE）的罕见病因。1994年3月至6月，在一家拥有400张床位的社区医院诊断出4例近平滑念珠菌性PVE。瓣膜置换术后出现症状的平均时间为148天（范围为20至345天）。4例患者中有3例死于PVE并发症。进行了多次环境培养，只有一次培养出近平滑念珠菌呈阳性。来自体外循环泵、细胞回收器、心脏停搏液以及后续瓣膜的培养均为阴性。所有瓣膜置换手术均由同一手术室团队进行。对参与所有病例的仅有的两名人员，即外科医生和医师助理进行访谈发现，他们使用的低敏手套在瓣膜置换手术过程中经常撕裂，每次手术通常需要更换几次手套。采集了相关人员的手部培养物，20人（26%）的培养物中近平滑念珠菌呈阳性。最后一例手术后8个月采集的外科医生和医师助理的手部培养物中未检测到酵母菌。使用限制性内切酶BssHII和EagI对3株可用的病例分离株、14株流行病学上无关的患者分离株、1株环境分离株和20株手部分离株的基因组DNA进行电泳核型分析和限制性内切酶分析，随后进行脉冲场凝胶电泳，以进行分子分型。通过基因组DNA的限制性内切酶分析，3例病例分离株相同，其中2例具有相同的电泳核型图谱。其余的患者、环境和手部分离株代表29种不同的DNA类型，与病例分离株明显不同。所有测试的分离株对两性霉素B、5-氟胞嘧啶、氟康唑和伊曲康唑均敏感。间接证据表明在瓣膜置换手术期间手套撕裂以及随后近平滑念珠菌传播给患者的可能性。
