ICU患者艰难梭菌分离培养与流行病学特征研究

目的 了解ICU患者艰难梭菌的定植和感染情况，为预防艰难梭菌的流行提供参考。方法 收集2016年9月至2017年6月福建医科大学附属第一医院ICU中139例住院时间＞7 d的患者的粪便样本，对其进行选择性厌氧培养和质谱鉴定。对艰难梭菌培养阳性标本进行毒素基因（tcdA、tcdB、cdtA、cdtB）的PCR检测以及毒素A、B表型检测。收集所有患者的临床资料，并对艰难梭菌培养阳性患者的临床特征和实验室检查结果进行单因素分析和多因素回归分析。结果 艰难梭菌检出率为17.27%（24/139）。其中，14株艰难梭菌的tcdA和tcdB基因检测阳性，占58.3%（14/24）；10株为tcdA和tcdB基因检测阴性，占41.7%（10/24）。所有菌株二元毒素基因（ctdA/ctdB）均未检出。单因素分析提示，高龄、长时间住院、高淋巴细胞数、使用β-内酰胺类抗生素是艰难梭菌定植的高危因素；多因素回归分析提示，使用β-内酰胺类抗生素是艰难梭菌定植的独立危险因素（OR=3.881，P=0.039）。结论 我院ICU可能存在艰难梭菌感染和传播的风险，对具有高龄、长期住院以及使用抗生素等高危因素的患者应进行艰难梭菌的监测，以防艰难梭菌的传播、感染和艰难梭菌相关性腹泻的发生。

Epidemiological characteristics and isolation of Clostridium difficile in intensive care unit of a teaching hospital

Objective To evaluate the colonization or epidemic status of Clostridium difficile infection in intensive care unit (ICU) so as to provide reference data for effective control and prevention of Clostridium difficile. Methods A total of 139 stool samples were collected from patients who were hospitalized for over 7 days in ICU during September 2016 to June 2017 at First Affiliated Hospital of Fujian Medical University. All stools were anaerobic cultured by selective medium and identified by matrix-assisted laser desorption ionization time of flight mass spectrometry system MALDI Biotyper for Clostridium difficile. The toxin genes (tcdA, tcdB, cdtA, cdtB) were detected for the positive isolates by PCR. The clinical data of patients were collected and analyzed through univariate analysis and multivariate analysis. Results The detection rate of Clostridium difficile was 17.27% (24/139). 58.3%(14/24) of the detected Clostridium difficile were positive for tcdA and tcdB gene expression. 41.7%(10/24) of the detected Clostridium difficile were negative for tcdA and tcdB genes expression. No binary toxin gene was detected in any of the isolates. Univariate analysis showed that older in age, long hospital stay, high lymphocyte count and β-lactam antibiotics use were close association with acquisition of Clostridium difficile colonization in ICU patients. Multivariate analysis showed that β-lactam antibiotics use (OR=3.881, P=0.039) was an independent risk factor for acquisition of Clostridium difficile colonization. Conclusion The ICU department of our hospital are at risk of the infection and spread of Clostridium difficile. It is necessary to monitor the surveillance of Clostridium difficile in such group of patients such as older in age, long-term hospitalized, etc. and take effective prevention measures for the spread of Clostridium difficile.