重庆地区临床分离肺炎链球菌血清型及耐药分析基因多态性

目的 了解重庆地区的临床分离肺炎链球菌的常见血清型分布及其耐药情况,并对常见血清型菌株和其它血清型菌株的耐药情况进行比较.方法 应用荚膜肿胀实验检测2006年1月～2008年8月临床分离的143株肺炎链球菌的血清型,并采用琼脂稀释法检测常用抗菌药物的最低抑菌浓度(MIC).结果 总的常见血清型为型/群为19群、6群、5型、10群、15群,但从成人分离的菌株常见血清型为19群、10群、5型、33群,儿童则以19群、6群、15群和23群血清型为主.143株菌对阿奇霉素、克林霉素、左氧氟沙星、头孢唑林、青霉素的耐药率(耐药+中介)分别是97.9%、95.8%、4.2%、0.7%、58.1%,对于青霉素的敏感率是42%.常见血清型肺炎链球菌对5种抗菌素的耐药率(耐药+中介)分别是:97.7%、97.7%、1.1%、3.4%、72.4%;其它血清型菌的耐药率分别是:98.2%、92.9%、5.4%、0、35.7%.;仅青霉素耐药率有统计学意义差别.结论 重庆地区临床分离的肺炎链球菌的常见血清型与其它地区报道有一定差别.对左氧氟沙星、头孢唑林耐药率低,对青霉素的耐药率与国内报道接近,但对于阿奇霉素及克林霉素的耐药率高.常见血清型肺炎链球菌对青霉素的耐药率明显高于其它血清型.

Resistance and serotype of Streptococcus pneumoniae isolated from clinical patients in Chongqing

Objective To investigate antibiotic resistance and the prevalence of serotype of clinical Streptococcus pneumoniae in Chongqing. Methods One hundred and forty-three strains were isolated from in-paterns in four teaching hospitals in chongqing during 2006～2008. Minimal inhibition concentrations (MlC) of 5 kinds of antibiotics were determined by agar dilution method. The 143 strains were typed by the pneumotest-kit. Results Among 143 strains of Streptococcus pneumonia, the most prevalent serogroups/ serotypes are type 19,6 4,15,10 and 33. The rest 15 strains were unable to classify their serotypes. The common serogroup/serotypes of 63 clinical isolates from children are type 19, 6,15,14 and 23, while those from adults (80 strains) are type 19,5,10 and 33. Of all isolates, penicillin susceptible rate is 42%; clindamycin and azthromycin resistance were 94.4% and 97.9% respectively, worthy to calling for clinical attention. The Strains resistant to levofloxacin and cefazolin were found for 4.2%, and 0.7%. Penicillin susceptible rate of the most common serogroup/serotypes was 27.6%, while those of uncommon serogroup/serotypes were 64.3%. The azthromycin, clindamycin, levofloxacin, cefazolin and penicillin resistance rates for the common serogroup/serotypes strains were 97.7%, 97.7%, 1.1%, 3.4% and 72.4% .respectively; while those of the uncommon serogroup/serotypes were 98.2%, 92.9%, 5.4%, 0 and 35.7% respectively.Conclusions Among 143 strains of S. pneumoniae, The most prevalent serogroups/ serotypes are 19 ,6 ,5,15,10 and 33, the most common serotypes of the clinical isolates from children were different from adults. The isolates in Chongqing had higher penicillin susceptibility than those in other area. The isolates had a significantly higher susceptible rate of levofloxacin and cefazolin, but the isolates had a higher clindamycin and azthromycin resistance. The most prevalent serogroups/ serotypes had a different resistance rate to penicillin compared with the uncommon serogroup/serotypes isolates.