鲍曼不动杆菌在全球医疗保健环境中构成了重大挑战,分离株表现出前所未有的碳青霉烯耐药性。这里,我们对2020年9月至2021年11月期间在科钦的一家教学医院回收的鲍曼不动杆菌分离株(n=64)进行了表征,南印度。用blaOXA-51样PCR确认分离物的物种身份。鉴定出的主要碳青霉烯酶决定簇是blaOXA-23样(45,70.3%)和blaNDM-1(31,48.4%);在27个(42.2%)分离株中也观察到了这些基因的共存。确定的其他抗性基因包括blaPER(34,53.1%),aac(6')-Ib-cr(42,65.6%),qnrS(25,39.1%),sul1(32,50%),sul2(33,51.6%),strA/strB(36,56.3%),aphA1-Iab(35,54.7%)和tetB(32,50%)。映射PCR揭示了插入元素,在所有具有该基因的分离物中,位于blaOXA-23样上游的ISAbaI。关于消毒剂抗性,所有分离株都携带季铵化合物(QAC)抗性基因,qacEΔ1。苯扎氯铵的最小抑制浓度(MIC)在分离物中很高,范围为8至128µgml-1。然而,氯己定和三氯生的MIC较低,大多数(54,80.6%)的分离株对氯己定的MIC为2µgml-1,所有分离株对三氯生的MIC为≤0.125µgml-1。Further,所有分离株都是强大的生物膜生产者,通过基于结晶紫的微量滴定板测定法评估。ApaI脉冲场凝胶电泳(PFGE)揭示了分离株的多克隆性质,有16个簇和16个独特的脉型在80%的临界值鉴定。总之,这项研究提供了有关该地区鲍曼不动杆菌分子特征的有用数据,这可能有助于评估这种病原体的当地流行病学,也有助于制定感染控制策略。
Acinetobacter baumannii poses a significant challenge in healthcare settings across the globe, with isolates exhibiting carbapenem resistance at unprecedented rates. Here, we characterized a collection of A. baumannii isolates (n=64) recovered during the period September 2020 - November 2021 at a teaching hospital in Cochin, South India. The species identity of the isolates was confirmed with bla OXA-51-like PCR. The major carbapenemase determinants identified were bla OXA-23-like (45, 70.3 %) and bla NDM-1 (31, 48.4 %); co-occurrence of these genes was also observed in 27 (42.2 %) isolates. Other resistance genes identified included bla PER (34, 53.1 %), aac(6\')-Ib-cr (42, 65.6 %), qnrS (25, 39.1 %), sul1 (32, 50 %), sul2 (33, 51.6 %), strA/strB (36, 56.3 %), aphA1-Iab (35, 54.7 %) and tetB (32, 50 %). Mapping PCR revealed the insertion element, ISAbaI upstream of bla OXA-23-like in all isolates possessing this gene. Concerning disinfectant resistance, all isolates carried the quaternary ammonium compound (QAC) resistance gene, qacEΔ1. Minimal inhibitory concentration (MIC) of benzalkonium chloride was high among the isolates and ranged from 8 to 128 µg ml-1. However, low MICs were observed for chlorhexidine and triclosan, with the majority (54, 80.6 %) of isolates showing an MIC of 2 µg ml-1 for chlorhexidine and all isolates exhibiting MICs of ≤0.125 µg ml-1 for triclosan. Further, all isolates were strong biofilm-producers, as assessed by the crystal violet-based microtitre plate assay. The ApaI-pulsed-field gel electrophoresis (PFGE) revealed the multi-clonal nature of the isolates, with 16 clusters and 16 unique pulsotypes identified at a cut-off of 80 %. In short, this study provides useful data on the molecular features of A. baumannii from this region, which could be helpful to assess the local epidemiology of this pathogen and also to devise infection control strategies.