宁波地区腹泻患者细菌性病原检测与分析

Etiological analysis of diarrhea in Ningbo

目的了解宁波地区腹泻患者病原菌构成和耐药性,为防控感染性腹泻提供依据。方法病原菌检测采用直接分离与增菌分离相结合的方法;细菌筛检和鉴定采用生化和生化鉴定试剂条API等法,鉴定到种、群;病原菌血清分型采用血清凝集法;药敏试验采用K-B法;耐药基因检测采用PCR法,统计学分析采用SPSS 11.0软件包进行,率的比较采用χ2检验和F分析。结果 9 256份标本中检出8类16种3 473株病原菌,检出率为37.52%,其中,副溶血性弧菌、沙门菌和气单胞菌的检出率分别为16.13%(1 493/9 256)、3.99%(369/9 256)和3.44%(318/9 256),副溶血性弧菌的检出率明显高于其他病原菌(χ2=21.68,P<0.01);血清分型发现副溶血性弧菌的O3群(349/480)、沙门菌的甲型副伤寒菌(168/369)、志贺菌的褔氏志贺菌(117/175)、致病性大肠埃希菌O119(28/66)为各病原菌的优势菌,检出了褔氏1C、2C和4C志贺菌新亚型;药敏试验显示病原菌对大多数抗生素敏感,但有45株为多重耐药菌,其中气单胞菌23株、志贺菌8株、致泻性大肠埃希菌8株、金黄色葡萄球菌3株、变形杆菌2株、沙门菌1株,占总菌数的2.45%,检出了bla-TEM、sull和aacc等3种耐药基因。结论宁波地区感染性腹泻病原构成复杂,副溶血性弧菌是最主要的流行病原菌;检出褔氏C型志贺菌提示其血清型可能或正在转换,需加强对志贺菌变迁的监测,以预防疾病的暴发;致病性不强的气单胞菌和类志贺邻单胞菌检出率较高,应引起关注;耐药菌株中有2.45%的病原菌为超广谱β-内酰胺酶(ESBL)菌株,涉及多个菌属,提示临床治疗中合理用药是减少耐药菌的传播和扩散的关键。

Objective To analyze the pathogens of diarrhea and to determine the drug resistance of bacteria in Ningbo. Methods A total of 9 256 stool samples of patients with diarrhea were collected. Pathogenic bacteri a were isolated and identified. Sero-agglutinating test was used for bacteria serotyping and K-B method for bac teria antimicrobial susceptibility test. Drug resistance genes were identified by PCR. Results A total of 3 473 pathogenic bacteria strains were isolated and clustered into 8 serotypes and 16 species. The detection rate of Vibrio parahemolyticus was the highest of 16, 13%, followed by Salmonella of 3. 99%. 03, Salmonella paratyphi A, Sh. fle,rneri and 0119 were found to be the dominant serotypes of Vibrio parahemolyticus, Salmonella, Shigella and enteropathogenic E. coli EPEC. New subtypes 1C, 2C and 4C of Shigellae F were also identified. Majority of pathogenic bacteria strains were sensitive to most antibiotics. Only 45 strains were found to be multidrug resistant and half were Aeromonas bacteria. Conclusions Variety of bacteria causing diarrhea are found in Ningbo, and Vibrio parahemolyticus are the major pathogenic ones. The finding of new Shigellae F serotypes suggests the change of se- rotype of Shigellae. Surveillance for this change should be strengthened in order to prevent the outbreak.