背景:这项工作报告了西班牙侵袭性化脓性链球菌的抗菌素耐药性数据,由“侵袭性A组链球菌监测计划”收集,2007-2020年。
方法:通过测序确定emm分型。对青霉素的易感性,四环素,红霉素,和克林霉素通过E检验测定。tetM,tetO,msrD,mefa,ermB,ermTR,和ermT通过PCR寻找。大环内酯抗性表型(M,cMLSB,和iMLSB)使用红霉素-克林霉素双盘试验检测。抗性克隆通过它们的emm类型鉴定,多位点序列类型(ST),抗性基因型,和大环内酯耐药表型。
结果:青霉素敏感性普遍。237/1983分离株对四环素的耐药性(12.0%)(152只携带tetM,48只携带tetO,和33携带两者)。在172/1983分离株中检测到红霉素耐药性(8.7%);ermB在83中存在,mefA在58中存在,msrD在51中存在,ermTR在46中存在,ermT在36中存在。在78/1983分离株中存在克林霉素抗性(甲基化酶介导的)(3.9%)。确定了八个主要的抗性克隆:两个仅对四环素具有抗性(emm22/ST46/tetM和emm77/ST63/tetO),三种仅对红霉素耐药(emm4/ST39/mefA-msrD/M,emm12/ST36/mefA-msrD/M,和emm28/ST52/ermB/cMLSB),和三个四环素-红霉素共耐药(emm11/ST403/tetM-ermB/cMLSB,emm77/ST63/tetO-ermTR/iMLSB,和emm77/ST63/tetM-tetO-ermTR/iMLSB)。
结论:四环素,红霉素,2007年至2020年间,克林霉素耐药率下降。抗性克隆比例的时间变化决定了抗性率的变化。
BACKGROUND: This work reports on antimicrobial resistance data for invasive Streptococcus pyogenes in Spain, collected by the \'Surveillance Program for Invasive Group A Streptococcus\', in 2007-2020.
METHODS: emm typing was determined by sequencing. Susceptibility to penicillin, tetracycline, erythromycin, and clindamycin was determined via the E-test. tetM, tetO, msrD, mefA, ermB, ermTR, and ermT were sought by PCR. Macrolide-resistant phenotypes (M, cMLSB, and iMLSB) were detected using the erythromycin-clindamycin double-disk test. Resistant clones were identified via their emm type, multilocus sequence type (ST), resistance genotype, and macrolide resistance phenotype.
RESULTS: Penicillin susceptibility was universal. Tetracycline resistance was recorded for 237/1983 isolates (12.0%) (152 carried only tetM, 48 carried only tetO, and 33 carried both). Erythromycin resistance was detected in 172/1983 isolates (8.7%); ermB was present in 83, mefA in 58, msrD in 51, ermTR in 46, and ermT in 36. Clindamycin resistance (methylase-mediated) was present in 78/1983 isolates (3.9%). Eight main resistant clones were identified: two that were tetracycline-resistant only (emm22/ST46/tetM and emm77/ST63/tetO), three that were erythromycin-resistant only (emm4/ST39/mefA-msrD/M, emm12/ST36/mefA-msrD/M, and emm28/ST52/ermB/cMLSB), and three that were tetracycline-erythromycin co-resistant (emm11/ST403/tetM-ermB/cMLSB, emm77/ST63/tetO-ermTR/iMLSB, and emm77/ST63/tetM-tetO-ermTR/iMLSB).
CONCLUSIONS: Tetracycline, erythromycin, and clindamycin resistance rates declined between 2007 and 2020. Temporal variations in the proportion of resistant clones determined the change in resistance rates.