头孢他啶对家兔产CTX-M-14型超广谱β内酰胺酶细菌性腹膜炎的治疗作用

Therapeutic effect of ceftazidime in a rabbit model of peritonitis caused by Escherichia coli producing CTX-M-14 extend ed-spectrum β-lactamase

目的确定头孢他啶对产CTX-M-14型超广谱β内酰胺酶(ESBLs)大肠埃希菌所致的细菌性腹膜炎的治疗效果。方法在家兔腹腔内注射产CTX-M-14型ESBLs接合菌3×108CFU/ml,制备家兔细菌性腹膜炎模型。应用随机数字表法将133只制备成细菌性腹膜炎模型的家兔分为4组,1组为对照组(33只),另3组在注射细菌4h后分别给予头孢他啶(32只)、头孢噻肟(34只)、哌拉西林/他唑巴坦(34只)治疗。密切观察家兔体温和外周血白细胞和中性粒细胞变化,记录家兔存活情况及大网膜病理变化。结果给予抗菌药物治疗的3组家兔在注射细菌48h后体温恢复正常,而对照组6d后体温才恢复正常。头孢他啶组家兔的病死率(22%,7/32)与头孢噻肟组(50%,17/34)和对照组(52%,17/33)的病死率比较差异均有统计学意义(χ2值分别为5·64、6·13,P均<0·05)。头孢他啶组家兔腹腔脓肿发生率(16%,4/25)与对照组(50%,8/16)比较差异有统计学意义(校正的χ2=3·93,P<0·05)。治疗结束时头孢他啶组家兔升高的外周血白细胞下降至基础水平,头孢噻肟组和对照组的白细胞仍高于基础水平。头孢他啶组的以上结果均和哌拉西林/他唑巴坦组相似,差异无统计学意义(P>0·05)。各组大网膜病理组织学镜下检查炎性细胞浸润及脓肿形成程度经秩和检验,差异无统计学意义(P>0·05)。结论头孢他啶对产CTX-M-14型ESBLs大肠埃希菌腹膜炎有较好疗效。

Objective To study the therapeutic effect of ceftazidime （CAZ） in a rabbit model of peritonitis caused by Escherichia coli producing CTX-M-14 extended-spectrum β-1actamase （ESBL） . Methods The peritonitis model was produced by intra-abdominal injection of a mixture of 3×10^8 CFU/ml Escherichia coli producing CTX-M-14 ESBL and 10% BaSO4. All rabbits were randomized into four groups. Four hours after the bacteria were injected, three groups were intramuscularly administered ceftazidime （100 mg/kg, twice a day）, ceftaxime （ 100 mg/kg, twice a day） and piperacillin/tazobactam （ 225 mg/kg, every 8 h） respectively. The fourth group did not receive any therapy as a control. The temperature, leucocyte counts and percentage of neutrophils were closely observed. The dying time of rabbits was recorded and anatomized immediately, and pathology of the great omentum was examined. Results The temperature of the control group became normal on the 6th day, while the temperature of the other three groups returned normal 48 h after the injection of the bacteria. Compared with the mortality of the ceftaxime-treated group （50%） and the control group （52%）, the mortality of the ceftazidime-treated group （22%）was significantly decreased（x^2 =5.64,6. 13,P 〈 0.05）. The administration of ceftazidime also inhibited the incidence of abdominal abscess in the survived rabbits（ 16% ） in comparison with the control group（50% ,x^2 =3.93 ,P 〈 0. 05）. In addition, the leucocyte counts of the ceftazidime-treated group returned normal at the end of treatment, while those of the ceftaxime group and the control group were still high. The above measurements showed no difference between the ceftazidime-treated group and the piperacillin/tazobactam-treated group（ P 〉 0. 05 ）. Conclusion Ceftazidime showed good therapeutic effect in peritonitis caused by Escherichia coli producing CTX-M-14 ESBL