Department of Clinical Examination, The Children's Hospital, Urumqi, Xinjiang, China.
Department of Biology, University of Maryland, College Park, Maryland, USA.
Foodborne Pathog Dis. 2022 Aug;19(8):522-528. doi: 10.1089/fpd.2021.0113. Epub 2022 Aug 1.
Multiple drug-resistant (MDR) isolates have been reported worldwide. Between May 2017 and September 2018, 55 2a isolates were collected from 3322 stool samples of 0-10-year-old outpatients with diarrhea at the Children's Hospital of Urumqi, China. All isolates were characterized using serotyping, antimicrobial susceptibility testing, and whole-genome sequencing. A total of 54 of 55 (98.2%) isolates exhibited MDR phenotypes and had accumulated multiple resistance determinants, particularly of fluoroquinolones and cephalosporins preferred for shigellosis treatment: point mutations in quinolone resistance-determining regions (QRDRs) of topoisomerases (GyrA (S83L, D87N) and ParC (S80I) [ = 9]; GyrA (S83L) and ParC (S80I) [ = 45]) and acquisition of ( = 3) and ( = 8). Over 70% of isolates acquired two point mutations of GyrA (S83L) and ParC (S80I) in QRDRs and 11 highly resistant isolates accumulated three point mutations in QRDRs or acquired . Four 2a isolates from three single-nucleotide polymorphism clusters exhibited coresistance to ciprofloxacin, cefotaxime, or azithromycin (AZM), which are used as first- and second-line shigellosis treatment antimicrobials in clinics. Our data indicated that fluoroquinolones should be terminated in shigellosis treatment for outpatients in Urumqi. The transferable antimicrobial resistance determinants have been identified for third-generation cephalosporins and AZM. Novel strategies are urgently required for developing empirical medication to reduce the antimicrobial selective pressure and prevent dissemination of MDR 2a isolates.
据报道，全球范围内出现了多重耐药（MDR）分离株。2017 年 5 月至 2018 年 9 月，从中国乌鲁木齐儿童医院 3322 份 0-10 岁腹泻门诊患者的粪便样本中采集了 55 株 2a 分离株。所有分离株均通过血清分型、抗菌药物敏感性试验和全基因组测序进行了特征描述。55 株分离株中，有 54 株（98.2%）表现出 MDR 表型，并积累了多种耐药决定因素，特别是氟喹诺酮类和头孢菌素类药物，这些药物常用于治疗志贺菌病：拓扑异构酶喹诺酮耐药决定区（QRDRs）中的点突变（gyrA（S83L，D87N）和 parC（S80I）[=9]；gyrA（S83L）和 parC（S80I）[=45]）和获得（[=3]和[=8]）。超过 70%的分离株在 QRDRs 中获得了 gyrA（S83L）和 parC（S80I）的两个点突变，11 株高度耐药的分离株在 QRDRs 中积累了三个点突变或获得了[=3]。来自三个单核苷酸多态性群集的 4 株 2a 分离株对临床上用于志贺菌病治疗的一线和二线抗菌药物环丙沙星、头孢噻肟或阿奇霉素（AZM）表现出协同耐药。我们的数据表明，氟喹诺酮类药物应在乌鲁木齐门诊志贺菌病治疗中停用。已经确定了可转移的抗菌药物耐药决定因素，包括第三代头孢菌素和 AZM。迫切需要制定新的策略，以开发经验性药物，减少抗菌药物的选择性压力，防止 MDR 2a 分离株的传播。
