Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA.
J Clin Microbiol. 2019 Oct 23;57(11). doi: 10.1128/JCM.00968-19. Print 2019 Nov.
There are sparse data to indicate the extent that macrolide-resistant (MRMp) occurs in the United States or its clinical significance. Between 2015 and 2018, hospitals in 8 states collected and stored respiratory specimens that tested positive for and sent them to the University of Alabama at Birmingham, where real-time PCR was performed for detection of 23S rRNA mutations known to confer macrolide resistance. MRMp was detected in 27 of 360 specimens (7.5%). MRMp prevalence was significantly higher in the South and East (18.3%) than in the West (2.1%). A2063G was the predominant 23S rRNA mutation detected. MICs for macrolide-susceptible (MSMp) were ≤0.008 μg/ml, whereas MICs for MRMp were 16 to 32 μg/ml. Patients with MRMp infection were more likely to have a history of immunodeficiency or malignancy. Otherwise, there were no other significant differences in the clinical features between patients infected with MRMp and those infected with MSMp, nor were there any differences in radiographic findings, hospitalization rates, viral coinfections, the mean duration of antimicrobial treatment, or clinical outcomes. There was no significant change in MRMp incidence over time or according to age, sex, race/ethnicity, or status as an inpatient or an outpatient. Patients with MRMp were more likely to have received a macrolide prior to presentation, and their treatment was more likely to have been changed to a fluoroquinolone after presentation. This is the first national surveillance program for in the United States. Additional surveillance is needed to assess the clinical significance of MRMp and to monitor changes in MRMp prevalence.
目前仅有少量数据表明大环内酯类耐药（MRMp）在美国的发生程度及其临床意义。2015 年至 2018 年期间，8 个州的医院采集并储存了呼吸道标本，这些标本经检测对呈阳性，并被送往阿拉巴马大学伯明翰分校，在那里进行了实时 PCR 检测，以检测已知可导致大环内酯类耐药的 23S rRNA 突变。在 360 个标本中检测到 27 个（7.5%）MRMp。MRMp 的流行率在南部和东部（18.3%）显著高于西部（2.1%）。检测到的主要 23S rRNA 突变是 A2063G。对大环内酯类敏感（MSMp）的 MICs 为≤0.008μg/ml，而对 MRMp 的 MICs 为 16 至 32μg/ml。MRMp 感染患者更有可能有免疫缺陷或恶性肿瘤病史。否则，MRMp 感染患者与 MSMp 感染患者在临床特征、影像学发现、住院率、病毒合并感染、抗菌治疗的平均持续时间或临床结果方面没有任何显著差异。MRMp 的发生率在时间上或根据年龄、性别、种族/民族或住院或门诊状态没有显著变化。MRMp 患者在就诊前更有可能接受过大环内酯类药物治疗，并且他们的治疗在就诊后更有可能更改为氟喹诺酮类药物。这是美国首个全国性的 监测计划。需要进一步的监测来评估 MRMp 的临床意义，并监测 MRMp 流行率的变化。
