头孢菌素类在医院内感染中的治疗作用的探讨

AN EPIDEMIOLOGICAL INVESTIGATION AND TNE MANAGEMENT OF NOSOCOMIAL INFECTIONS

本文报道作者等自1985年6月至1987年6月的两年内对华山医院进行医院内感染的前瞻性流行病学调查.两年共调查1826例,其中194例(10.6%)发生院内感染、感染总例次数为239.总发病率13.1%.各病房院内感染的发病率依次为皮肤科19.8%、内科16.8%、外科14.8%、神经内科13.7%、神经外科12.7%等、感染的部位依次为:肺部45.2%、尿路18%、伤口10%、肝、胆道75%、败血症5%、皮肤、腹腔、胃肠道等感染发生率均低于5%.在调查中共分离得院内感染菌株271株,其中革兰阳性球菌62株(22.9%)、主要为金葡菌、表萄苗、肠球菌.革兰阴性杆菌180株,(66.4%),主要为绿脓杆菌、肺炎杆菌、大肠杆菌等.此外还有念珠菌、曲菌等.药敏试验结果显示金葡菌中93.5%对青霉素耐药,对红霉素、四环素、氯霉素、氨基糖甙类等的耐药率在60～80%以上,金葡菌对万古霉素均呈敏感,大肠、肺炎、绿脓杆菌等对四环素的耐药率为70～100%.大肠杆菌对氨苄、羧苄青霉素耐药者约50%,肺炎杆菌对两者耐药者在90%以上,头孢呋新对大肠杆菌、肺炎杆菌、变形杆菌等多数肠杆菌科细茵具良好抗菌活性,远较头孢噻吩为强;与头孢孟多相比,头抱呋新对肠杆菌属和部分不动杆菌属的抗菌活性亦较前者为强.值得注意的是,除普通变形、沙雷氏菌、硝酸盐阴性杆菌和绿脓杆菌外,头孢呋新对多数革兰阴性杆菌的抗菌活性均优于庆大霉素.头孢他啶对革兰阴性杆菌的抗菌活性与丁胺卡那霉素相似,对绿脓杆菌的作用远较头孢噻肟为强.根据Schumacher提出的评价抗菌药物有效性的两项指标,Cssmax/MIC与Ⅱ(72)(Intensity Index),头孢呋新和头孢他啶的上述指标分别为第二代和第三代头孢菌素中最高者,根据以上资料,作者提出头孢呋新和头孢他啶在治疗医院内感染中的适用范围。

A prospective epidemiological study of nosocomial infections was car-ried out at the Hua Shan Hospital, Shanghai Medical University, China, from 1985 to1987. The total number or patients investigated were 1826, or whom 194 (10. 6%) con-tracted nosocomial infection while in hospital. The number of episodes or infection was239, representing an incidence of 13. 1%.The indidence of nosocomial infections in hospi-tal wards is in the following order of frequency: dermatology 19.8%. internal medicine16.8%, surgery 14.8%, neurology 13.7%. neurosurgery 12.7% etc.The sites of infectionincluded lung 45. 2%, urinary tract 18%, wound 10%, biliary fract 7. 5%, andsepticemia 5%. The inciuemce in other sites of infection were all less than 5%. A total of 271 bacterial strains were isolated from these nosocomial infections, ofthese 62 (22. 9%) were Gram (+) cocci, most of them being staph. aureus.staph. epidermidis and enterococci; 180 (66. 4%) Gram (-) rods, most being Psacruginosa, K.pneumoniae and E coli.Some candida spp and aspergillus spp.were also iso-lated. Sensitivity tests showed that 93.5% of the Staph aureus were resistant to penicillin,the resistance rates to erythromycin, tetracycline, chloramphenicol and aminoglycosideswere in the range of 60-80% or more; while all were highly sensitive to vancomycin. Theresistance rates or E coli, K pneumoniae and Ps aeruginosa to tetracycline were 70-100%, about 50% of the E coli strains were resistant to ampicillin and carbenicillin, while morethan 90% of the K pneumoniae strains were resistant to both drugs.Cefuroxime (CXM) hasgood activity against E coli, K pneumoniac and most strains of Enterobacteriaceae, beingmore active than cephalothin.Compared with cefamandole, CXM was more active againstenterobacter and some of the acinetobacter strains.It is worthy or note that CXM was moreactive than GM against most Gram negative organisms tested except strains or Pmirabi1is, Serratia, A anitratum and Ps aeruginosa. The antibacterial activity ofceftazidime (CTZ) against Gram negative rods was similar to that or amikacin, being moreactive than cefotaxime against Ps aeruginosa.According to the indices evaluating the clini-cal efficacy of antibiotics proposed by Schumacher, the Css / MIC and Ⅱ (72) of CXMand CTZ are the highest among the second and third generation cephalosporinsrespectively. Based on the above data, the role of CXM and CTZ in the treatment ofnosocomial infections were discusseed 15.