细菌感染患者246例血培养阳性结果分析

Analysis of 246 cases of positive blood culture

目的研究血液感染的微生物种类和病因。方法血液标本在BacT/Alert3D240全自动培养仪中培养,采用BioMerieuxAPI系统鉴定。结果246例血培养阳性患者共分离出细菌247株,其中革兰阴性菌163株,占660%,革兰阳性菌75株,占304%,真菌9株,占36%,感染率最高的细菌是大肠埃希菌、甲型副伤寒菌、伤寒沙门菌及非金葡葡萄球菌。血液感染中内科疾病占825%、外科疾病占41%、其他占134%,415%的患者以发热为主要症状。776%的沙门菌分离自呼吸科和急诊科患者,大肠埃希菌主要见于肾内科、血液科及外科患者。非金葡葡萄球菌主要见于呼吸科和儿科患者。血培养涂片诊断的准确率为996%。标本在孵育12、24、36、48、72、96h的阳性率依次为244%、740%、874%、931%、972%和992%。结论快速血培养技术是血液感染病原学诊断必要手段。

Objective To investigate the kinds of isolates and the causes of bloodsream infection.Methods A total of 4 459 blood samples were cultured by BacT/Alert 3D240. The isolates were identified by API system.Results 247 strains were isolated from 246 patients. The isolates included Gram-negative bacteria (66.0%), Gram-positive bacteria (30.4%) and fungi(3.6%). E. coli, Salmonella paratyphi A , Salmonella typhi and Staphylococcus sp. not-Staphy. aureus were the main pathogen. The causes of bloodstream infection resulted from non-surgical disease, surgical disease, and others were 82.5%, 4.1% and 13.4%, respectively. The major symptom of blood infection was fever, which was presented in 41.5% of positive blood culture cases. 77.6% of Salmonella sp. was isolated from the patients of the department of respiratory and the department of emergency. E. coli was mainly isolated from the patients of the department of nephrolgy, haemotology and surgical department. Staphycoccus sp.not-Staphy. aureus was mainly isolated from the patients of the department of respiratory and pediatrics. The positive blood culture rate in 12,24,36,48,72,96 h were 24.4%,74.0%,87.4%,93.1%,97.2%, and 99.2% respectively.The coincidence rate of positive blood culture detected under microscope and identified by API system was ~99.6%. Conclusion Automated blood culture systems were important apparatus for diagnosis of bloodstream infection.