Datta Amitesh, Gandham Nageswari, Vyawahare Chanda R, Mirza Shahzad, Bhatia Savita, Shinde Prajakta B
Department of Microbiology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth, Pune, Maharashtra, India.
Int J Appl Basic Med Res. 2025 Apr-Jun;15(2):91-97. doi: 10.4103/ijabmr.ijabmr_498_24. Epub 2025 Apr 7.
is an alarming pathogen in hospital-acquired infections, particularly in the intensive care units (ICUs). Carbapenemases production and biofilm formation contribute significantly to the pathogenicity of the organism. Carbapenem resistance in is primarily due to the production of carbapenemases.
The study was conducted to detect the presence of carbapenemase-encoding genes in along with their ability to form biofilm. In addition, this study also investigated the association between biofilm formation and carbapenemase genes harboring isolates.
One hundred and forty isolates of were collected from the various specimens. Of these, this study included 36 isolates that were carbapenem-resistant, metallo-β-lactamases (MBLs) producing, and extensively drug-resistant (XDR) obtained from ICUs. Identification and antibiotic susceptibility determination was done using VITEK 2. Further, the isolates were confirmed by detecting the OXA-51 carbapenemase gene intrinsic to . Polymerase chain reaction was performed to detect carbapenemase-encoding genes, and biofilm formation was examined using the tube method.
The OXA-51 gene was present in all isolates ( = 36). showed highest sensitivity against colistin (100%) and minocycline (25%). Out of 36 isolates, acquired carbapenemase encoding genes were detected in 35 (97.22%) isolates, as follows: OXA-23 (35/36, 97.22%), NDM (18/36, 50%), IMP (1/36, 2.78%), and VIM (28/36, 77.78%). In 33 (91.67%) isolates, oxacillinase (OXA) and MBL genes coexisted. Among the 36 isolates, 30 (83.33%) formed biofilm.
The study highlights that colistin and minocycline are the viable antibiotics for treating carbapenem-resistant MBL-producing XDR infections. OXA-23 is the commonest carbapenemase gene, and VIM is the most frequently found MBL gene prevalent in our hospital and contributes to carbapenem resistance in . The study also showed a higher frequency of co-occurrence of multiple carbapenemase genes in single isolates, and most of these isolates formed biofilm. However, no statistically significant association was found between biofilm formation and carbapenemase genes in . This study emphasizes the molecular diagnostic value of carbapenemase gene detection to reduce the resistance rate in isolates.
[病原体名称]是医院获得性感染中一种令人担忧的病原体，尤其是在重症监护病房（ICU）。碳青霉烯酶的产生和生物膜形成对该病原体的致病性有显著贡献。[病原体名称]对碳青霉烯类药物的耐药性主要归因于碳青霉烯酶的产生。
本研究旨在检测[病原体名称]中碳青霉烯酶编码基因的存在及其形成生物膜的能力。此外，本研究还调查了[病原体名称]分离株生物膜形成与携带碳青霉烯酶基因之间的关联。
从各种标本中收集了140株[病原体名称]分离株。其中，本研究纳入了36株从ICU获得的对碳青霉烯类耐药、产金属β-内酰胺酶（MBL）且广泛耐药（XDR）的分离株。使用VITEK 2进行鉴定和抗生素敏感性测定。此外，通过检测[病原体名称]固有的OXA-51碳青霉烯酶基因来确认分离株。进行聚合酶链反应以检测碳青霉烯酶编码基因，并使用试管法检查生物膜形成。
所有分离株（n = 36）均存在[病原体名称]OXA-51基因。[病原体名称]对黏菌素（100%）和米诺环素（25%）表现出最高敏感性。在36株分离株中，35株（97.22%）检测到获得性碳青霉烯酶编码基因，如下：[病原体名称]OXA-23（35/36，97.22%）、[病原体名称]NDM（18/36，50%）、[病原体名称]IMP（1/36，2.78%）和[病原体名称]VIM（28/36，77.78%）。在33株（91.67%）分离株中，氧青霉烯酶（OXA）和MBL基因共存。在36株分离株中，30株（83.33%）形成了生物膜。
该研究强调黏菌素和米诺环素是治疗耐碳青霉烯类产MBL的XDR[病原体名称]感染的可行抗生素。[病原体名称]OXA-23是最常见的碳青霉烯酶基因，[病原体名称]VIM是我院最常见的MBL基因，导致[病原体名称]对碳青霉烯类耐药。该研究还表明单个分离株中多种碳青霉烯酶基因共现的频率较高，且这些分离株大多形成生物膜。然而，在[病原体名称]中未发现生物膜形成与碳青霉烯酶基因之间存在统计学上的显著关联。本研究强调了碳青霉烯酶基因检测在降低[病原体名称]分离株耐药率方面的分子诊断价值。
