安徽省芜湖市2018年百日咳疑似病例病原菌药敏与基因型分析

目的 了解芜湖市百日咳鲍特氏菌耐药情况及其流行菌株的基因型,为百日咳的有效防治提供依据。方法 将2018年5月—2018年12月芜湖市第一人民医院收治百日咳疑似病例为研究对象,所有入组对象于入院时采集鼻咽拭子,进行百日咳鲍特氏菌培养和PCR检测,并对4株留存菌株进行药敏与基因型检测。结果 百日咳疑似病例70例,年龄0.1~12.0岁,平均（2.38±2.61）岁,其中7例为4月龄之内婴儿未接种疫苗。经细菌培养阳性18例,阳性率为25.71%,PCR检测阳性20例,阳性率28.57%,差异无统计学意义。41例使用大环内酯类抗生素患儿细菌培养与PCR检测阳性率为分别为12.20%（5/41）和17.07%（7/41）,29例未使用大环内酯类抗生素患儿细菌培养与PCR阳性率均为44.83%（13/29）,是否使用大环内酯类抗生素对细菌培养与PCR阳性率影响比较差异均有统计学意义（χ²=9.469,6.411,P<0.05）。随机抽取4株百日咳鲍特氏菌进行药敏试验与基因型检测,4株均对红霉素、克林霉素耐药,而对左氧氟沙星、复方新诺明和氨苄西林均敏感。4株基因型均为ptxA1/ptxC1/ptxP1/prn1/fim2-1/fim3-1和tcfA2,均与我国当前百日咳鲍特氏菌疫苗菌株型ptxA2/ptxC1/ptxP1/prn1/fim2-1/fim3-1和 tcfA2不同。结论 在当前疫苗时代,以临床诊断标准诊断百日咳可靠性不足,有必要进行实验室检测确诊,疫苗接种后感染百日咳的现象需要引起重视;本地区目前流行菌株与疫苗菌株不相匹配,需进一步监测流行菌株的基因型,为疫苗制备提供参考。

Drug susceptibility and genotype analysis of suspected pertussis cases in Wuhu,Anhui, 2018

Objective To investigate the drug resistance and genotype of Bordetella pertussis strains in Wuhu city, and to provide evidence for effective prevention and control of pertussis. Methods A total of 70 suspected pertussis cases admitted to Wuhu First People's Hospital from May 2018 to December 2018 were selected as the study subjects. All the enrolled subjects were collected pharyngeal swabs of pertussis immediately after admission, and Bordetella pertussis culture and PCR detection were performed, and the drug sensitivity and genotype of 4 retained strains were detected. Results There were 70 suspected cases of pertussis, aged from 0.1 to 12.0 years old, with an average age of (2.38±2.61) years old, among which 7 cases were infants under 4 months old who had not been vaccinated. The number of positive cases in bacterial culture was 18, with a positive rate of 25.71%, and the number of positive cases in PCR detection was 20, with a positive rate of 28.57%. The difference between the two methods was not statistically significant (χ²=2.751, P>0.05). The positive rates of bacterial culture and PCR of 41 children who were given macrocyclic antibiotics were 12.20%（5/41） and 17.07%（7/41）, respectively. The bacterial culture and PCR positive rates of 29 children who did not use macrocyclic antibiotics were both 44.83% (13/29), whether antibiotics were used or not had a statistically significant difference in the effect of bacterial culture and PCR positive rate(χ²=9.469, 6.411, P<0.05). Four of the 18 positive bacterial culture cases were tested for drug sensitivity and genotype, and all the four strains of Bordetella pertussis were resistant to erythromycin and clindamycin, but sensitive to levofloxacin and cotrimoxazole. The genotypes（ptxA1/ptxC1/ptxP1/prn1/fim2-1/fim3-1/tcfA2） of the 4 strains isolated during this time were different from current pertussis Bordetella vaccine strains（ptxA2/ptxC1/ptxP1/prn1/fim2-1/fim3-1/tcfA2）in China. Conclusions In the current vaccine era, the reliability of clinical diagnostic criteria for pertussis is insufficient, and it is necessary to conduct laboratory tests for confirmation; and the phenomenon that people were infected with Bordetella pertussis after vaccination needs to be paid more attention; The current prevailing strains in the region does not match the vaccine strain, so it needs to be further monitored to provide a reference for vaccine preparation.