中国部分地区淋球菌耐药监测点产青霉素酶淋球菌及其 blaTEM-135突变体的流行调查

Penicillinase-producing Neisseria gonorrhoeae and its blaTEM-135 gene variants at several gonococcal antimicrobial surveillance sites in China：an epidemiological study

目的：了解中国不同地区淋球菌耐药监测点产青霉素酶淋球菌（PPNG）的比例及 blaTEm-135突变体在 PPNG 中的分布，比较 PPNG 及 blaTEm-135突变体淋球菌多抗原测序分型（NG-MAST）的型别分布，了解不同地区 PPNG blaTEm-135突变体的差异与联系。方法2012年在江苏、上海、浙江、天津、广东、广西6个淋球菌耐药监测点共收集572株淋球菌，经过分离纯化及鉴定后，采用头孢噻吩纸片法测定 PPNG；菌株培养后利用试剂盒提取 DNA，通过错配扩增突变分析 PCR（MAMA PCR）鉴定 blaTEm-135突变体，采用 NG-MAST 进行分型研究。结果572株淋球菌中 PPNG 总阳性率为38.1%（218/572），PPNG 中相应 blaTEm-135突变体的总比例为52.3%（114/218）。监测点中 PPNG 阳性率从高至低分别为：浙江（45/87，51.7%）、上海（36/79，45.6%）、广东（78/205，38.0%）、广西（12/32，37.5%）、江苏（24/77，31.2%）、天津（23/92，25%）；PPNG 中相应 blaTEm-135突变体的阳性率从高至低分别为：浙江（31/45，68.9%）、江苏（14/24，58.3%）、广东（39/78，50.0%）、上海（17/36，47.2%）、天津（9/23，39.1%）、广西（4/12，33.3%）。 NG-MAST 分型研究显示，blaTEm-135突变体中流行菌株型别有 ST2318、ST1768、ST1866、ST1053、ST8726等，其中 ST1768、ST1053和 ST8726与 blaTEm-135突变体有较强的对应关系。天津 PPNG 菌株及 blaTEm-135突变体 ST 分布与其他各监测点有显著差异，江浙沪地区菌株 ST 有一定联系。结论中国淋球菌耐药监测点 PPNG 及相应 blaTEm-135突变体阳性率处于较高水平，不同地区间 PPNG 及相应 blaTEm-135突变体阳性菌株 ST 型别分布差异有统计学意义。

Objective To determine the prevalence of penicillinase-producing Neisseria gonorrhoeae（PPNG） and the distribution of blaTEm-135 gene variants in PPNG at several gonococcal antimicrobial surveillance sites in China, to compare N. gonorrhoeae multi-antigen sequence typing（NG-MAST）types of PPNG and its blaTEm-135 gene variants, and to assess the difference and association in NG-MAST types of blaTEm-135 gene variants among different regions. Methods A total of 572 N. gonorrhoeae isolates were collected at 6 gonococcal antimicrobial surveillance sites from Jiangsu, Shanghai, Zhejiang, Tianjin, Guangdong and Guangxi in 2012. After isolation, purification, and identification, cefalotin paper discs were used for detection of PPNG. DNA was extracted by QIAxtractor DX kits after cultivation of the PPNG strains. Then, mismatch amplification mutation assay （MAMA） PCR was performed to identify blaTEm-135 variants, and NG-MAST analysis to determine N. gonorrhoeae genotypes. Results Among the 572 N. gonorrhoeae strains, 38.1%（218/572） were identified as PPNG, and of the PPNG strains, 52.3% （114/218） were blaTEm-135 variants. The detection rate of PPNG at these surveillance sites from high to low was as follows： 51.7% （45/87, Zhejiang）, 45.6%（36/79, Shanghai）, 38.0% （78/205, Guangdong）, 37.5% （12/32, Guangxi）, 31.2% （24/77, Jiangsu） and 25.0%（23/92, Tianjin）, and that of blaTEm-135 variants was as follows： 68.9%（31/45, Zhejiang）, 58.3%（14/24, Jiangsu）, 50.0%（39/78, Guangdong）, 47.2%（17/36, Shanghai）, 39.1%（9/23, Tianjin）and 33.3%（4/12, Guangxi）. NG-MAST analysis showed that the ST2318, ST1768, ST1866, ST1053 and ST8726 types predominated among these bla TEm-135 variants, and a strong correlation was found between blaTEm-135 variants and some NG-MAST types, such as ST1768, ST1053 and ST8726 types. The distribution of NG-MAST types was significantly different between the surveillance site in Tianjin （in the Northern part of China） and the other sites （in the Southern part of China）, but highly similar among the surveillance sites in Jiangsu, Zhejiang and Shanghai regions. Conclusions There is a high prevalence of PPNG and its blaTEm-135 variants at several gonococcal antimicrobial surveillance sites in China, with significant differences in NG-MAST genotype distribution of PPNG and its blaTEm-135 variants among different regions.