Jai Prakash Narayan Apex Trauma Centre, All India Institute of Medical Sciences, New Delhi, India.
US Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Infect Control Hosp Epidemiol. 2019 Dec;40(12):1387-1393. doi: 10.1017/ice.2019.252. Epub 2019 Oct 18.
Resistance to colistin, a last resort antibiotic, has emerged in India. We investigated colistin-resistant Klebsiella pneumoniae(ColR-KP) in a hospital in India to describe infections, characterize resistance of isolates, compare concordance of detection methods, and identify transmission events.
Retrospective observational study.
Case-patients were defined as individuals from whom ColR-KP was isolated from a clinical specimen between January 2016 and October 2017. Isolates resistant to colistin by Vitek 2 were confirmed by broth microdilution (BMD). Isolates underwent colistin susceptibility testing by disk diffusion and whole-genome sequencing. Medical records were reviewed.
Of 846 K. pneumoniae isolates, 34 (4%) were colistin resistant. In total, 22 case-patients were identified. Most (90%) were male; their median age was 33 years. Half were transferred from another hospital; 45% died. Case-patients were admitted for a median of 14 days before detection of ColR-KP. Also, 7 case-patients (32%) received colistin before detection of ColR-KP. All isolates were resistant to carbapenems and susceptible to tigecycline. Isolates resistant to colistin by Vitek 2 were also resistant by BMD; 2 ColR-KP isolates were resistant by disk diffusion. Moreover, 8 multilocus sequence types were identified. Isolates were negative for mobile colistin resistance (mcr) genes. Based on sequencing analysis, in-hospital transmission may have occurred with 8 case-patients (38%).
Multiple infections caused by highly resistant, mcr-negative ColR-KP with substantial mortality were identified. Disk diffusion correlated poorly with Vitek 2 and BMD for detection of ColR-KP. Sequencing indicated multiple importation and in-hospital transmission events. Enhanced detection for ColR-KP may be warranted in India.
黏菌素耐药性在印度出现。我们在印度的一家医院调查了耐黏菌素肺炎克雷伯菌（ColR-KP），以描述感染情况，分析分离株耐药性特征，比较检测方法的一致性，并确定传播事件。
回顾性观察性研究。
将 2016 年 1 月至 2017 年 10 月期间从临床标本中分离出 ColR-KP 的个体定义为病例患者。通过肉汤微量稀释法（BMD）确认 Vitek 2 检测到的耐黏菌素的分离株。对分离株进行药敏试验，包括纸片扩散法和全基因组测序。查阅病历。
在 846 株肺炎克雷伯菌中，有 34 株（4%）对黏菌素耐药。共发现 22 例病例患者。大多数（90%）为男性；中位年龄为 33 岁。一半的患者是从另一家医院转来的；45%的患者死亡。在检测到 ColR-KP 之前，病例患者的中位住院时间为 14 天。此外，有 7 例（32%）在检测到 ColR-KP 之前接受过黏菌素治疗。所有分离株均对碳青霉烯类耐药，对替加环素敏感。Vitek 2 检测到的耐黏菌素的分离株也通过 BMD 检测到；2 株耐 ColR-KP 的分离株通过纸片扩散法检测到。此外，还鉴定了 8 种多位点序列类型。分离株中未检测到移动性黏菌素耐药基因（mcr）。基于测序分析，可能有 8 例（38%）病例患者发生了院内传播。
发现了由高耐药性、mcr 阴性、死亡率高的 ColR-KP 引起的多重感染。纸片扩散法与 Vitek 2 和 BMD 检测 ColR-KP 的相关性较差。测序表明存在多次输入和院内传播事件。印度可能需要加强对 ColR-KP 的检测。
