Oztürk Fatma, Gündeş Sibel, Işik Cavit
Kocaeli Universitesi Tip Fakültesi, Klinik Bakteriyoloji ve Enfeksiyon Hastaliklari Anabilim Dali, Izmit.
Mikrobiyol Bul. 2008 Jan;42(1):17-27.
This study was aimed to assess the frequency, risk factors and etiology of bacteremia and antimicrobial susceptibilities of strains isolated from adult bacteremic patients hospitalized in Kocaeli University Hospital, Turkey during a 12-month period. Blood specimens obtained from a total of 2602 patients after at least 48 hours of hospitalization, were cultured in aerobic BACTEC 9120 and BACTEC 9050 (Becton-Dickinson, USA) automatized systems, and the identification and antibiotic susceptibilities of bacteria were performed by VITEK 1 (bioMerieux, France) system. Blood cultures of a total of 385 (14.7%) patients yielded bacterial growth; the contamination rate being 9.1% (238/2602) and nosocomial bacteria rate being 5.6% (147/2602). The distribution of the 147 (81 female, 67 male) bacteremic patients were as follows: 45% internal ward, 28% surgical ward and 27% intensive care unit. A total of 148 patients (81 female, 67 male) with no growth in their blood cultures were randomly chosen as the control group. The pathogens isolated from nosocomial bacteremias revealed 101 gram-positive bacteria (68.7%), 39 gram- negative bacilli (26.5%) and seven Candida species (4.7%). The most frequent gram-positive bacteria were staphylococci 84/101; 83.1%) and gram-negative bacteria were E. coli (14/39; 35.8%). Coagulase negative staphylococci (CNS) were isolated from 79% of the cultures evaluated as contaminants. Methicillin resistance was determined in 61.6% of S. aureus and 68.1% of CNS. Extended spectrum beta-lactamases were detected in 64% of E. coli, 62% of Pseudomonas spp., 47% of Klebsiella spp. and 24% of Acinetobacter spp. and resistance rates to ceftazidime and beta-lactam/beta-lactamase inhibitor combinations in these strains were 39-67%. The most effective drug group was found to be carbapenems with 3-26% resistance rates. The evalution of risk factors between patient and control groups revealed that mechanical ventilation (p < 0.05) and interventional catheters (except for intravenous catheters) (p < 0.05) were the most frequent sources of bacteremias. The most frequent focus of infection were the lungs (29.9%), followed by abdominal and catheter originated infections (23.8% each). The high rate of antibiotic resistance determined in the nosocomial bacterial isolates in our hospital indicated that antibiotic use policies in our setting should be taken under control. The high rate of contamination in blood cultures emphasize that more attention should paid for continous education about collection of blood culture specimens.
本研究旨在评估土耳其科贾埃利大学医院收治的成年菌血症患者在12个月期间菌血症的发生率、危险因素、病因以及分离菌株的抗菌药敏情况。从2602例患者住院至少48小时后采集的血标本，在有氧BACTEC 9120和BACTEC 9050（美国BD公司）自动化系统中培养，细菌的鉴定和药敏试验通过VITEK 1（法国生物梅里埃公司）系统进行。共有385例（14.7%）患者的血培养有细菌生长；污染率为9.1%（238/2602），医院感染菌率为5.6%（147/2602）。147例（81例女性，67例男性）菌血症患者的分布如下：内科病房占45%，外科病房占28%，重症监护病房占27%。随机选择148例血培养无细菌生长的患者（81例女性，67例男性）作为对照组。医院感染菌血症分离出的病原体包括101株革兰阳性菌（68.7%）、39株革兰阴性杆菌（26.5%）和7种念珠菌（4.7%）。最常见的革兰阳性菌是葡萄球菌84/101（83.1%），革兰阴性菌是大肠埃希菌（14/39；35.8%）。凝固酶阴性葡萄球菌（CNS）在79%被评估为污染菌的培养物中分离得到。金黄色葡萄球菌和CNS的耐甲氧西林率分别为61.6%和68.1%。大肠埃希菌、铜绿假单胞菌、克雷伯菌属和不动杆菌属中分别有64%、62%、47%和24%检测到超广谱β-内酰胺酶，这些菌株对头孢他啶和β-内酰胺/β-内酰胺酶抑制剂联合制剂的耐药率为39%-67%。发现最有效的药物组是碳青霉烯类，耐药率为3%-26%。患者组和对照组之间危险因素的评估显示，机械通气（p<0.05）和介入性导管（静脉导管除外）（p<0.05）是最常见的菌血症来源。最常见的感染部位是肺部（29.9%），其次是腹部和导管相关感染（各占23.8%）。我院医院感染细菌分离株中确定的高耐药率表明，应控制我院的抗生素使用策略。血培养中的高污染率强调，应更加重视血培养标本采集的持续教育。
