产ESBLs肺炎克雷伯菌的致病性及头孢他啶疗效分析

Pathogenicity of ESBLs-producing Klebsilla pneunmoniae and analyse on therapeutic effect of ceftazidime

目的探讨产ESBLs肺炎克雷伯菌不同感染途径的致病性差异及头孢他啶对产ESBLs肺炎克雷伯菌腹腔感染小鼠的保护作用。方法分别采用滴鼻途径建立小鼠呼吸道感染模型和腹腔注射途径建立小鼠腹腔感染模型,将小鼠分成6组,检测产ESBLs肺炎克雷伯菌对小鼠的半数致死量。另将头孢他啶体外药敏试验敏感的产ESBLs肺炎克雷伯菌腹腔感染小鼠分成3组,采用不同治疗方法考察头孢他啶的体内治疗作用,同时与亚胺培南/西司他丁钠疗效做对比分析。结果产ESBLs肺炎克雷伯菌经过滴鼻途径感染小鼠未见死亡,经腹腔感染途径的半数致死量为105;头孢他啶预防给药组小鼠的死亡率为10%,同时给药与感染4h后给药组小鼠的死亡率为30%,头孢他啶对产ESBLs肺炎克雷伯菌腹腔感染小鼠的保护作用与亚胺培南/西司他丁钠作用一致。结论产ESBLs肺炎克雷伯菌经呼吸道感染途径的致病性比腹腔感染途径弱,头孢他啶体外药敏试验敏感的产ESBLs肺炎克雷伯菌感染可以采用头孢他啶治疗,但应尽早使用。

OBJECTIVE To investigate the pathogenicity＇s difference of ESBLs-producing Klebsiella pneunmoniae in different route of infection in mice and the protection of ceftazidime on mice infected by ESBLs-producing K. pneunmoniae through abdominal cavity. METHODS The half lethal dose of ESBLs-producing K. pneunmoniae to mice infected through nose and abdominal cavity were detected. The mice infected by ceftazidime-sensitive ESBLs-producing K. pneunmoniae through abdominal cavity were divide into 3 groups and the therapeutical effect of ceftazidime were investigated through different therapeutical methods. RESULTS All mice infected ESBLs-producing K. pneunmoniae through nose did not die. The half lethal dose of ESBLs-producing K. pneunmoniae through abdominal cavity were 105. The death rate of mice infected ceftazidime-sensitive ESBLs-producing K. pneunmoniae through abdominal cavity in the ceftazidime medication administration groups of prophylaxis, simultaneous and infected 4 hours were 10%, 30%, 30%, respectively. The protection of ceftazidime on mice infected by ESBLs-producing K. pneunmoniae was equal with Imipenem/Cilastatin （IPM）. CONCLUSION The pathogenicity＇s of ESBLs-producing K. pneunmoniae through respiratory infection in mice is weaker than abdominal cavity infection. Ceftazidime can treat the infection of ceftazidime-sensitive ESBLs-producing K. pneunmoniae.