用3种药敏方法评价流感嗜血杆菌对3种β-内酰胺类药物的药敏实验一致性的研究

A Study on the Consistency of Three Methods for Detecting the Susceptibility of Haemophilus Influenzae to Threeβ-Lactams Drugs

目的对比研究3种体外药敏试验在测定流感嗜血杆菌(Haemophilus influenzae,Hi)对氨苄西林、阿莫西林克拉维酸、头孢呋辛等3种β-内酰胺类药物敏感的可靠性及实用性。方法采用肉汤稀释法、纸片扩散法(K-B法)和自动化微量肉汤稀释法(ATB法)检测Hi对氨苄西林、阿莫西林克拉维酸、头孢呋辛的药物敏感性。以肉汤稀释法为参考方法,分析比较K-B法和ATB法结果间的一致性和误差率。结果K-B法与肉汤稀释法对氨苄西林、阿莫西林克拉维酸、头孢呋辛的药敏一致率分别为77.19%、91.58%、69.16%,ATB法与肉汤稀释法的一致率分别为70.18%、73.16%、51.98%,K-B法对阿莫西林克拉维酸、头孢呋辛这两种药物的一致率显著高于ATB法。结果误差方面,K-B法对氨苄西林和头孢呋辛的重大误差率和极重大误差率都显著低于ATB法,K-B法对阿莫西林克拉维酸的重大误差率也显著低于ATB法。结论检测Hi对β-内酰胺抗生素药敏实验方面,K-B法和肉汤稀释法的一致性较好;ATB法对Hi药敏试验产生的误差较大。临床工作中报告ATB法药敏结果时,应结合β-内酰胺酶试验,出现异常药敏表型,或者对ATB药敏结果有疑问时,建议联合使用其他药敏方法,对ATB法结果进行修正。

Objective To compare the reliability and feasibility of three testing methods for assessing the effectiveness of Ampicillin,Amoxicillin-clavulantic acid,and Cefuroxime against isolates of Hi in vitro.Methods K-B method and ATB method were compared with referencing broth dilution method for assessing the effectiveness and consistency of Ampicillin,Amoxicillin-clavulantic acid,and Cefuroximeagainst Hi isolated clinically.Results The agreement between K-B method and broth dilution method for Ampicillin,Amoxicillin-clavulantic acid,and Cefuroxime were 77.19%,91.58%,and 69.16%,respectively.The concordance rate between ATB method and broth dilution method for the four drugs were 70.18%,73.16%,and 51.98%,respectively.The concordance rates of K-B method were statistically higher than ATB method for Amoxicillin-clavulantic acid and Cefuroxime.The major error and very major error of ATB for Ampicillin and Cefuroxime were significantly higher than K-B.Meanwhile,the major error of ATB for Amoxicillin-clavulantic acid was statistically higher than K-B.Conclusion For the detection of Hi susceptibility toβ-lactam antibiotics,the consistency of K-B method is better than that of ATB method.Furthermore,the error of the Hi susceptibility test is higher by using ATB method than by the K-B method.When we report the drug sensitivity results of ATB method in clinical work,we should combine results ofβ-lactamases test.When developing abnormal phenotype of drug sensitivity,or if there are any doubts about the results of drug sensitivity of ATB,we suggest to use other drug sensitive methods together to revise the results of ATB method.