摘要
目的 了解儿童肺炎链球菌携带者耐药菌株的流行情况 ,比较携带者菌株血清型与肺炎链球菌结合疫苗血清型的符合率 ,寻找单个患儿同时携带敏感和耐药菌株的可能性。方法 (1)对1997年 11月～ 12月在北京儿童医院普通门诊登记的 3个月～ 5岁儿童进行问卷调查 ;(2 )采集鼻咽拭子和尿标本 ,培养、分离和鉴定肺炎链球菌 ,并测定尿标本中的抗生素活性 ;(3)根据NCCLS方法使用微量稀释法测定肺炎链球菌对青霉素、头孢呋新、头孢噻肟、复方新诺明、红霉素和氯霉素的敏感性 ;(4 )从最初发现的青霉素、红霉素敏感株中寻找“隐匿性耐药克隆株”。结果 (1) 5 0 2例受试儿童中 ,分离出 190株肺炎链球菌 ,携带率为 37.8% (190 / 5 0 2 ) ,对青霉素的敏感率为 91.1% ;(2 )只有33 .9%的菌株血清型与建议使用的肺炎链球菌结合疫苗血清型相符 ;(3) 4 2例含青霉素和红霉素敏感菌株鼻咽拭子中发现 6株 (14% )“隐匿性耐药克隆株”。结论 在携带者中 ,肺炎链球菌对 β 内酰胺类耐药还不常见 ,但对红霉素和复方新诺明耐药却非常严重 ;建议使用的结合疫苗血清型不能覆盖大部分携带菌株 ;耐药菌株的小部分隐匿在敏感菌株中 。
Objective Streptococcus pneumoniae (Sp) has long been one of the most important bacterial pathogen causing pneumonia, meningitis, otitis media, sinusitis, and septicemia. During the recent 2 decades, the resistance of Sp to penicillin has been rapidly increasing in many parts of the world. The authors designed the present study to determine the prevalence of drug resistance among streptococcus pneumoniae carried by children in China, to determine the prevalence of vaccine serotypes among carriage strains and to look for carriage of both susceptible and resistant Sp clones in individual patients. Methods The subjects enrolled 502 patients with upper respiratory infections who were 3 months to 5 years of age attending a general outpatient clinic at Beijing Children′s Hospital from Nov. to Dec.1997. A standardized questionnaire addressing age, symptoms of upper respiratory infections, recent antimicrobial use, breastfeeding, day care attendance, household size, smoke exposure, and parental education was completed for all the cases. Nasopharyngeal specimens and urine were collected for culture and antimicrobial activity, respectively. Sp was identified by optochin sensitivity and bile solubility. Sp serotyping was performed by using quelling reaction. Sensitivity to penicillin, cefuroxime, co trimoxazole, erythromycin, and chloramphenicol was determined using broth microdilution according to NCCLS methods. Urine sensitivity for antimicrobial activity was tested by pan susceptible Micrococcus luteus method. Forty two swabs were checked for “hidden clones” by selective plates containing penicillin or erythromycin compared to isolates found on gentamycin using antimicrobial susceptibility, serotype, and pulsed field gel electrophoresis (PFGE). Results Nasopharyngeal carriage of Sp among less than 5 years old children was 37.8% of the 502 subjects with upper respiratory infections. Beta lactam non susceptible strains remain uncommon (only 8%～9%) in this population. Resistance to erythromycin and co trimoxazole was very common (more than 70%). Only 33.9% of the isolates were those included in proposed pneumococcal conjugate vaccine formulations. Forty two samples containing Sp susceptible to both penicillin and erythromycin were tested for “hidden resistant clones” and 6 (14%) resistant clones were found. Conclusions Beta lactam resistance remains uncommon among the subjects studied in spite of widespread beta lactam use. However, it is necessary to monitor beta lactam resistance every year. Erythromycin and co trimoxazole resistance was very common. Erythromycin resistant strains were more common in children who recently took a macrolide. A small number of antibiotics resistant Sp strains were present in patients carrying susceptible Sp strains. Therefore, use of antimicrobial agents could lead to prominence of these resistant strains. Use of antibiotics might eradicate susceptible strains, but would leave the resistant strains alive in mucous membrane, which could be more dangerous for invasive disease. This study showed that the proposed conjugate vaccine serotypes did not cover majority of strains isolated; however, the distribution for invasive Sp strains may differ. Therefore, more studies should be done in this field in China.
出处
《中华儿科杂志》
CAS
CSCD
北大核心
2000年第7期424-427,共4页
Chinese Journal of Pediatrics
关键词
肺炎链球菌
儿童抗药性
克隆
抗生素
Streptococcus pneumoniae
Drug resistance, microbial
Vaccines, conjugate
Carrier state
