Neonatal Intensive Care Unit, Department of Paediatrics, School of Medicine, University of Patras, Patras, Greece.
Clin Microbiol Infect. 2011 Nov;17(11):1684-90. doi: 10.1111/j.1469-0691.2011.03489.x. Epub 2011 Apr 4.
An atypical pattern of coagulase-negative staphylococcal (CoNS) sepsis, characterized by persistence despite aggressive antibiotic therapy, has been described in neonates cared for in neonatal intensive-care units. Our aim was to analyse the clinical, microbiological and molecular determinants of this persistent CoNS bacteraemia. Neonates with late-onset CoNS bacteraemia were studied for a 2-year period. Demographic, clinical, laboratory, microbiological and molecular data were compared between neonates with persistent (≥3 consecutive positive blood cultures) and non-persistent CoNS bacteraemia. Twenty-nine infants with persistent and 43 with non-persistent bacteraemia were identified, with no significant differences regarding demographic and clinical characteristics between the two groups. Of a total of 170 CoNS isolates, 80 showed biofilm production (54 persistent and 26 non-persistent; p 0.013), whereas 127 were positive for the icaA and icaD genes (74 persistent and 53 non-persistent; p 0.598). Sixty ica-positive isolates did not produce slime, whereas 13 ica-negative isolates showed biofilm production. Endotracheal intubation and the presence of central vascular catheters were significant risk factors for persistent bacteraemia, but, in a logistic regression model, only biofilm production was significantly related to the persistent form of the disease (p 0.005). In this study, persistent CoNS sepsis in neonates requiring intensive care was not related to most of the known clinical risk factors, and it was associated with severe thrombocytopenia. Isolates associated with persistent bacteraemia were more likely to produce biofilm, independently of the presence of the ica operon.
凝固酶阴性葡萄球菌（CoNS）败血症的一种非典型模式，其特征是尽管采用了积极的抗生素治疗，但仍持续存在，这种情况在新生儿重症监护病房接受治疗的新生儿中已有描述。我们的目的是分析这种持续凝固酶阴性葡萄球菌菌血症的临床、微生物学和分子决定因素。对 2 年内发生晚发型凝固酶阴性葡萄球菌菌血症的新生儿进行了研究。比较了持续性（≥3 次连续阳性血培养）和非持续性凝固酶阴性葡萄球菌菌血症新生儿的人口统计学、临床、实验室、微生物学和分子数据。确定了 29 例持续性和 43 例非持续性菌血症的婴儿，两组间的人口统计学和临床特征无显著差异。在总共 170 株凝固酶阴性葡萄球菌分离株中，80 株显示生物膜生成（54 株持续性和 26 株非持续性；p=0.013），而 127 株为 icaA 和 icaD 基因阳性（74 株持续性和 53 株非持续性；p=0.598）。60 株 ica 阳性分离株不产生黏液，而 13 株 ica 阴性分离株显示生物膜生成。气管内插管和中央血管导管的存在是持续性菌血症的显著危险因素，但在逻辑回归模型中，只有生物膜生成与疾病的持续性形式显著相关（p=0.005）。在这项研究中，需要重症监护的新生儿持续性凝固酶阴性葡萄球菌败血症与大多数已知的临床危险因素无关，与严重血小板减少症相关。与持续性菌血症相关的分离株更可能产生生物膜，而与 ica 操纵子的存在无关。
