2008—2010年湖北省流感嗜血杆菌标本分布及耐药性分析

Distribution and antimicrobial resistance of clinical isolates of Haemophilus influenzae from Hubei province from 2008 to 2010

摘要:

目的了解湖北省不同地区分离的流感嗜血杆菌的分布及其耐药性。方法收集2008—2010年湖北省15所三级甲等医院临床分离的流感嗜血杆菌，采用纸片扩散法进行药敏试验，按照美国临床实验室标准化研究所（CLSI） 2009版标准判断结果；采用头孢硝噻吩纸片法检测产β内酰胺酶情况。结果共分离流感嗜血杆菌855株，主要分离自住院患者（673株，78.71%）；以呼吸道标本多见，占87.37%（747株）；成人分离575株（67.25%），儿童分离280株（32.75%），其中157株（56.07%）分离自2岁以下儿童。流感嗜血杆菌对复方磺胺甲口恶唑的耐药率最高，为58.0%，其他依次为氨苄西林42.9%、氯霉素16.9%、氨苄西林/舒巴坦16.2%，头孢呋辛、头孢噻肟、环丙沙星、左氧氟沙星和阿奇霉素的耐药率均＜10%。232株产β内酰胺酶，产酶率为27.13%；产β内酰胺酶率，成人分离株为22.26%，儿童分离株为37.14%。共分离32株β内酰胺酶阴性氨苄西林耐药株（BLNAR）。结论湖北省分离的流感嗜血杆菌主要分离自住院患者、呼吸道标本；对复方磺胺甲口恶唑和氨苄西林耐药率较高；儿童组β内酰胺酶检出率高于成人组。产β内酰胺酶是流感嗜血杆菌对氨苄西林耐药的主要机制。

Abstract:

ObjectiveTo investigate the distribution and antimicrobial  resistance of clinical isolates of Haemophilus influenzae (H. influenzae) from Hubei province.MethodsClinical isolates of H. influenzae were collected from 15 tertiary hospitals in Hubei province  from 2008 to 2010. Antimicrobial susceptibility testing was performed  by KirbyBauer disc diffusion method and results were analyzed according to CLSI 2009 guideline;βlactamase was detected with nitrocefin disk testing.ResultsA total of 855 H. influenzae isolates were collected, 673(78.71%) of which were from inpatients ; 87.37% (747 isolates) were from respiratory samples; 575 isolates (67.25%) were  from adults , and 280 (32.75%) from children,56.07% (157 isolates) of which were  from children under  2 years old . The resistant rate to trimethoprimsulfamethoxazole,ampicillin,chloramphenicol and ampicillin/sulbactam was  58.0%,42.9%,16.9% and 16.2%, respectively, the resistant rate to   cefuroxime, cefotaxime, ciprofloxacin, levofloxacin  and azithromycin were all <10%. 232 isolates (27.13%) produced betalactamase; 22.26% of adult isolates and  37.14% of child isolates  were betalactamase positive . A total of 32 isolates were  betalactamase negative ampicillinresistant (BLNAR) H. influenzae.ConclusionMost  isolated H. influenzae from  Hubei province were from respiratory samples of inpatients,the resistance  to trimethoprim/sulfamethoxazole and ampicillin are high, the prevalence of betalactamase isolates from children is higher than that from  adults. The primary mechanism of ampicillin resistance in H. influenzae is production of betalactamase.