Othman Hala B, Halim Rania Mohamed Abdel, Abdul-Wahab Hoda Ezz El-Arab, Atta Hossam Abol, Shaaban Omyma
Clinical Pathology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Plastic and Reconstructive Surgery Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Open Access Maced J Med Sci. 2018 Dec 15;6(12):2283-2289. doi: 10.3889/oamjms.2018.414. eCollection 2018 Dec 20.
This study aims to evaluate the ability of ChromID Carba agar, and Pseudomonas aeruginosa modified Hodge test (PAE-MHT) for detection of carbapenemase-producing P. aeruginosa and to determine the associated carbapenemase gene classes by PCR.
One hundred Carbapenem-resistant P. aeruginosa (CRPA) isolates were tested for: i) carbapenemases production by ChromID carba agar, Modified Hodge test (MHT) and (PAE-MHT) and ii) detection of some carbapenemase genes by PCR.
All (100%) of the isolates showed growth on ChromID Carba agar with 100% sensitivity. Using MHT, 54% of isolates were positive, 3% were indeterminate, and 43% were negative, demonstrating 58.9% sensitivity and 80% specificity. On performing PAE-MHT, 91% of the strains were positive, 3% were intermediate, and 6% were negative, demonstrating 97.9% sensitivity and 80% specificity. The most prevalent gene was blaKPC (81%), followed by blaVIM (74%); blaIMP was detected in only one isolate, and blaOXA-48 in 34% of the isolates.
We conclude that PAE-MHT and ChromID Carba are sensitive, specific, simple and cost-effective screening tests for detection of CRPA isolates compared to the traditional MHT.
本研究旨在评估ChromID Carba琼脂和铜绿假单胞菌改良 Hodge试验(PAE-MHT)检测产碳青霉烯酶铜绿假单胞菌的能力,并通过聚合酶链反应(PCR)确定相关的碳青霉烯酶基因类别。
对100株耐碳青霉烯铜绿假单胞菌(CRPA)分离株进行以下检测:i)使用ChromID carba琼脂、改良 Hodge试验(MHT)和(PAE-MHT)检测碳青霉烯酶的产生;ii)通过PCR检测一些碳青霉烯酶基因。
所有(100%)分离株在ChromID Carba琼脂上均生长,敏感性为100%。使用MHT时,54%的分离株为阳性,3%为不确定,43%为阴性,敏感性为58.9%,特异性为80%。进行PAE-MHT时,91%的菌株为阳性,3%为中间型,6%为阴性,敏感性为97.9%,特异性为80%。最常见的基因是blaKPC(81%),其次是blaVIM(74%);仅在1株分离株中检测到blaIMP,34%的分离株中检测到blaOXA-48。
我们得出结论,与传统的MHT相比,PAE-MHT和ChromID Carba是检测CRPA分离株的敏感、特异、简单且经济高效的筛查试验。