Department of Microbiology, Faculty of Medicine, University of Porto, Porto. Portugal.
Med Mycol. 2011 Apr;49(3):248-52. doi: 10.3109/13693786.2010.511633. Epub 2010 Aug 25.
A prospective study to assess fungaemia was conducted for 12 months at a Portuguese University Hospital. A total of 35 Candida albicans isolates obtained from 12 patients with fungaemia were compared by a multiplex PCR system using four microsatellite loci. Blood isolates were evaluated against concomitant isolates from urine, lower respiratory secretions and central venous catheters, as well as with successive isolates recovered from recurrent episodes of fungaemia. The data analyzed included the department of admission, underlying diseases and antifungal therapy. The susceptibility phenotypes of all isolates to amphotericin B, fluconazole, itraconazole, voriconazole and caspofungin were determined according to the CLSI M27-A3 protocol. We observed a high degree of similarity between successive blood isolates and between blood and concomitant isolates from other sites of the same patient. This is suggestive of the recurrence of fungaemia and was due to the same strain, possibly as a result of the failure of antifungal therapy. The genetic similarity observed between some strains isolated from different patients suggested the likelihood that they were hospital acquired. Distinct patients were infected by the same strain at different time periods, and an increase in antifungal resistance was observed over time for some of these strains. Hospital-acquired exogenous nosocomial infections can be associated with higher risks of antifungal resistance and need to be closely monitored. Particular attention should also be given to endogenous non-blood Candida isolates which can be critical in high risk patients, as they often can become invasive in immunodeficient individuals.
一项针对葡萄牙某大学医院的为期 12 个月的真菌血症前瞻性研究中，采用四重微卫星 PCR 系统对 12 例真菌血症患者的 35 株白色念珠菌分离株进行了比较。血液分离株与尿、下呼吸道分泌物和中心静脉导管中的同期分离株以及反复真菌感染血症患者的连续分离株进行了比较。分析的数据包括入院科室、基础疾病和抗真菌治疗。根据 CLSI M27-A3 方案，对所有分离株对两性霉素 B、氟康唑、伊曲康唑、伏立康唑和卡泊芬净的药敏表型进行了测定。我们观察到连续血液分离株之间以及同一患者的血液和同期其他部位分离株之间具有高度的相似性。这表明真菌感染血症的复发是由于同一菌株引起的，可能是由于抗真菌治疗失败。从不同患者分离的一些菌株之间观察到的遗传相似性表明，它们可能是医院获得的。不同患者在不同时期感染了同一菌株，并观察到其中一些菌株的抗真菌耐药性随时间增加。医院获得性外源性医院感染可能与更高的抗真菌耐药风险相关，需要密切监测。还应特别注意内源性非血液念珠菌分离株，因为它们在高危患者中可能具有重要意义，因为它们通常会在免疫功能低下的个体中变得具有侵袭性。
