Comparative study of phenotypic-based detection assays for carbapenemases in Acinetobacter baumannii

IF 1.4 4区医学 Q4 IMMUNOLOGY

Indian Journal of Medical Microbiology Pub Date : 2024-06-19 DOI:10.1016/j.ijmmb.2024.100640

Nouf Al-Rashed , Mohammad Shahid , Nermin Kamal Saeed , Abdullah Darwish , Ronni Mol Joji , Ali Al-Mahmeed , Khalid M. Bindayna

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引用次数: 0

Abstract

Background

Acinetobacter baumannii is a serious health concern worldwide, causing high mortality rates and limited medical therapy options. Carbapenem resistance is a significant problem in Acinetobacter baumannii isolates. The synthesis of acquired carbapenemases, such as oxacillinases, IMP, NDM, VIM, and KPC enzymes, causes carbapenem resistance.

Methods

A total of 106 non-repetitive, Acinetobacter baumannii isolates were collected from four major hospitals in Bahrain including 78 carbapenem-resistant Acinetobacter baumannii (CRAB), and 28 carbapenem-susceptible Acinetobacter baumannii (CSAB) isolates. Three phenotypic tests were investigated in this study: including CARBA NP, modified carbapenem inactivation method (mCIM)/EDTA-CIM (eCIM), and modified Hodge test (MHT).

Results

CARBA NP was positive in 50 tested CRAB isolates (100%), and the sensitivity was 100%. The MHT was positive in 73/106 isolates (68.8%), while the sensitivity and specificity of the MHT were 77.6% and 100%. Moreover, only 38/106 (35.8%) isolates were positive for mCIM/eCIM. The sensitivity and specificity of mCIM were 40.4% and 100%.

Conclusion

CARBA NP was ideal for phenotypic detection of carbapenemase production, followed by MHT. The m/eCIM demonstrated a lower detection rate in CRAB. Consequently, combining tests would be more accurate. The mCIM/eCIM can easily distinguish between MBLs and serine-carbapenemases due to the frequent co-production of these enzymes in A. baumannii. In hospital setups where molecular characterization tests are not available, CARBA NP seems to be an alternative test in combination with MHT or mCIM/eCIM.

查看原文本刊更多论文

基于表型的鲍曼不动杆菌碳青霉烯酶检测方法的比较研究。

背景：鲍曼不动杆菌是全球严重的健康问题，导致高死亡率和有限的医疗选择。在鲍曼不动杆菌分离株中，碳青霉烯类耐药性是一个重要问题。获得性碳青霉烯酶（如奥沙西林酶、IMP、NDM、VIM 和 KPC 酶）的合成会导致碳青霉烯类耐药性：方法：从巴林的四家主要医院共收集了 106 个非重复性鲍曼不动杆菌分离株，包括 78 个耐碳青霉烯类鲍曼不动杆菌（CRAB）和 28 个碳青霉烯类鲍曼不动杆菌（CSAB）分离株。本研究对三种表型检测方法进行了研究：包括 CARBA NP、改良碳青霉烯灭活法（mCIM）/ EDTA-CIM （eCIM）和改良霍奇试验（MHT）：CARBA NP 在 50 个检测的 CRAB 分离物中呈阳性（100%），灵敏度为 100%。改良霍奇检测（MHT）在 73/106 个分离株（68.8%）中呈阳性，灵敏度和特异性分别为 77.6% 和 100%。此外，只有 38/106 个分离物（35.8%）对 mCIM /eCIM 呈阳性。mCIM 的灵敏度和特异性分别为 40.4% 和 100%：结论：CARBA NP 是表型检测碳青霉烯酶产生的理想方法，其次是 MHT。在 CRAB 中，m/eCIM 的检出率较低。因此，联合检测会更准确。mCIM /eCIM 可以轻松区分 MBLs 和丝氨酸碳青霉烯酶，因为鲍曼不动杆菌中经常同时产生这些酶。在无法进行分子鉴定检测的医院中，CARBA NP 似乎是与 MHT 或 mCIM /eCIM 结合使用的另一种检测方法。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Indian Journal of Medical Microbiology IMMUNOLOGY-

CiteScore

2.20

自引率

0.00%

发文量

154

审稿时长

73 days

期刊介绍： Manuscripts of high standard in the form of original research, multicentric studies, meta analysis, are accepted. Current reports can be submitted as brief communications. Case reports must include review of current literature, clinical details, outcome and follow up. Letters to the editor must be a comment on or pertain to a manuscript already published in the IJMM or in relation to preliminary communication of a larger study. Review articles, Special Articles or Guest Editorials are accepted on invitation.