Abdalhamid B, Elhadi N, Alabdulqader N, Alsamman K, Aljindan R
Department of Pathology and Laboratory Medicine, King Fahad Specialist Hospital, Dammam, Saudi Arabia.
Department of Clinical Laboratory Science, College of Applied Medical Science, Saudi Arabia.
New Microbes New Infect. 2016 Jan 29;10:77-83. doi: 10.1016/j.nmni.2016.01.014. eCollection 2016 Mar.
Carbapenem-resistant Enterobacteriaceae (CRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPAE) are globally a major medical issue, especially in intensive care units. The digestive tract is the main reservoir for these isolates; therefore, rectal swab surveillance is highly recommended. The purpose of this study was to detect the prevalence of gastrointestinal tract colonization of CRE and CRPAE in patients admitted to intensive care units in Saudi Arabia. This project also aimed to characterize carbapenem-hydrolyzing enzyme production in these isolates. From February to May 2015, 200 rectal swab specimens were screened by CHROMagar KPC. Organism identification and susceptibility testing were performed using the Vitek 2 system. One CRE and 13 CRPAE strains were identified, for a prevalence of 0.5% (1/200) and 6.5% (13/200) respectively. Strains showed high genetic diversity using enterobacterial repetitive intergenic consensus sequence-based PCR. NDM type and VIM type were detected by PCR in four and one CRPAE isolates respectively. ampC overexpression was detected in eight CRPAE isolates using Mueller-Hinton agar containing 1000 μg/mL cloxacillin. CTX-M-15 type was detected in 1 CRE by PCR. The prevalence of CRE strain colonization was lower than that of CRPAE isolates. The detection of NDM and VIM in the colonizing CRPAE strains is a major infection control concern. To our knowledge, this is the first study in Saudi Arabia and the gulf region focusing on digestive tract colonization of CRE and CRPAE organisms and characterizing the mechanisms of carbapenem resistance.
耐碳青霉烯类肠杆菌科细菌（CRE）和耐碳青霉烯类铜绿假单胞菌（CRPAE）在全球范围内都是一个重大的医学问题，尤其是在重症监护病房。消化道是这些菌株的主要储存库；因此，强烈建议进行直肠拭子监测。本研究的目的是检测沙特阿拉伯重症监护病房患者中CRE和CRPAE胃肠道定植的患病率。该项目还旨在鉴定这些菌株中碳青霉烯水解酶的产生情况。2015年2月至5月，通过CHROMagar KPC筛选了200份直肠拭子标本。使用Vitek 2系统进行菌种鉴定和药敏试验。鉴定出1株CRE和13株CRPAE菌株，患病率分别为0.5%（1/200）和6.5%（13/200）。使用基于肠杆菌重复基因间共识序列的PCR，菌株显示出高度的遗传多样性。分别在4株和1株CRPAE分离株中通过PCR检测到NDM型和VIM型。在含有1000μg/mL氯唑西林的穆勒-欣顿琼脂上，在8株CRPAE分离株中检测到ampC过表达。通过PCR在1株CRE中检测到CTX-M-15型。CRE菌株定植的患病率低于CRPAE分离株。在定植的CRPAE菌株中检测到NDM和VIM是感染控制的一个主要问题。据我们所知，这是沙特阿拉伯和海湾地区第一项关注CRE和CRPAE生物体消化道定植并鉴定碳青霉烯耐药机制的研究。
