新生儿肺炎链球菌分离株对红霉素耐药性与耐药相关基因研究

Erythromycin Resistance and Resistance Related Genes Investigation of Isolated Streptococcus pneumoniae from Newborns

目的了解新生儿肺炎链球菌(SPN)临床分离株对红霉素耐药状况和红霉素耐药基因. 方法对2003年12月～2004年5月从常州市妇幼保健院新生儿病房呼吸道感染患者中分离到的20株SPN,用K-B法进行了红霉素药物敏感试验,用PCR检测了与红霉素耐药相关的红霉素核糖体甲基化酶基因(erm)、主动外排转运基因(mefA). 结果 20株SPN红霉素药敏试验17株耐药(85%),3株敏感;erm基因PCR检出20株阳性(100%)、mefA 基因PCR检出17株阳性(85.0%). 结论本地区SPN中因存在红霉素核糖体甲基化酶基因,红霉素主动外排转运体而致红霉素耐药;本研究20株肺炎链球菌erm 或(和)mefA基因阳性率高达100%,红霉素药敏试验与耐药基因检测均提示红霉素已不是治疗新生儿SPN感染的有效药物.

OBJECTIVE To investigate erythromycin resistance and erythromycin resistance genes of isolated Streptococcus pneumoniae from newborns. METHODS Twenty strains of S. pneumoniae were collected from respiratory system infected newborns from Dec 2003 to May 2004 at newborn ward of Changzhou Women and Children Health Care Hospital. Erythromycin sensitivity test was done by using K-B method. Genes related to erythromycin resistance such as erm, mefA were detected by PCR. RESULTS In all twenty strains, seventeen were erythromycin resistant, three were erythromycin sensitive, erm Gene was found in twenty strains（100%）, mefA gene was found in seventeen strains（85%）. CONCLUSIONS S. pneumoniae at this region was erythromycin resistant by containing erm and mefA genes. Twenty S. pneumoniae strains were all positive in erm/mefA test. Erythromycin sensitivity test and resistance gene detection show that erythromycin is no longer the effective drug for S. pneumoniae infection of newborns.