头孢米诺和其他14种抗菌药物对产与不产超广谱β-内酰胺酶菌株抗菌活性比较

目的测定头孢米诺和其他14种抗菌药物对产与不产超广谱β-内酰胺酶(ESBLs)菌株的体外抗菌活性.方法采用琼脂稀释法测定头孢米诺和其他14种抗菌药物的最小抑菌浓度(MIC),纸片确证法检测ESBLs.结果对110株产ESBL的大肠埃希菌和肺炎克雷伯菌,未发现亚胺培南耐药的菌株,除亚胺培南外,头孢米诺比其他的13种抗生素有较低的耐药性,其耐药率为7.3%,MIC50和MIC90值范围分别为0.5～1 mg/L和2～32 mg/L;对40株不产ESBLs的大肠埃希菌和肺炎克雷伯菌、头孢米诺、头孢美唑、头孢他啶、头孢噻肟、头孢曲松、头孢哌酮、头孢吡肟及亚胺培南,有相似的体外抗菌活性,其敏感率均为100%,MIC50和MIC90值范围分别为0.032～0.5 mg/L和0.064～4 mg/L.结论对产ESBL的大肠埃希菌和肺炎克雷伯菌,未发现亚胺培南耐药的菌株,头孢米诺比其他β-内酰胺类,庆大霉素和氟喹诺酮类有较高的体外抗菌活性;对不产ESBLs的菌株,头孢米诺、头孢美唑、头孢他啶、头孢噻肟、头孢曲松、头孢吡肟及亚胺培南有相同的抗菌活性,没有耐药的菌株发现.

In vitro Activity of Cefminox Against Extended Spectrum Beta-lactamases Producing and None-Producing Strains:A Comparison with Other 14 Antimicrobials

OBJECTIVE To determine in vitro antibiotic activity of cefminox and 14 other antimicrobials against extended spectrum beta-lactamases (ESBLs) producing and non-producing strains. METHODS MICs of cefminox and 14 other antimicrobials were determined by agar dilution susceptibility test and (ESBLs) were screened and conformed by disk diffusion method according to NCCLS recommended. RESULTS (Against) 110 strains producing ESBLs Escherichia coli and Klebsiella pneumoniae, none resistant strain was discovered to imipenem. Cefminox had lower resistance than other 13 antimicrobials excluded imipenem, its resistant rate was 7.3%. MIC_(50) and MIC_(90) value ranges of cefminox were 0.5-1 mg/L and 2-32 mg/L, respectively. Against 40 strains non-producing ESBLs E. coli and K. pneumoniae, cefminox had the same activity as cefmetazole, ceftazidime, cefotaxime, ceftriaxone, cefepime and imipenem, their susceptible rate was 100%, MIC_(50) and MIC_(90) value ranges were from (0.032) to 0.5 mg/L and from 0.064 to 4 mg/L. CONCLUSIONS Against (ESBLs-)producing E. coli and K. pneumoniae, cefminox is the highest active antibiotic except imipenem. Its activity is not only much better than other two cephamycins, but also more active than those of all beta-lactams, aminoglycosides and fluoroquinolones tested. Against producing ESBL-negative strains, cefminox has the same high activity as cefmetazole, ceftazidime, cefotaxime, ceftriaxone, cefepime and imipenem, no resistant strain is detected to those antimicrobials.