Ibrahim Yusuf, Sani Yahaya, Saleh Qabli, Saleh Algarni, Hakeem Gbadamosi
Department of Microbiology, Faculty of Science, Bayero University, Kano, Nigeria.
Department of Microbiology, King Abdulaziz University, Jeddah, Saudi Arabia.
Ethiop J Health Sci. 2017 Jan;27(1):3-10. doi: 10.4314/ejhs.v27i1.2.
Continue rise in unprofessional use of antibiotics in our hospitals and communities is worrisome. A research study was therefore conducted to detect extended spectrum beta-lactamase (ESBL), carbapenemase, metallobeta lactamase and their co-production phenotypically from isolates obtained from patients admitted to or attending two tertiary hospitals in Kano, Nigeria.
A total of 248 isolates of Escherichia coli and Klebsiella pneumoniaewere screened phenotypically for ESBL production and carbapenemase production according to CLS1 2012 breakpoints using double disk synergy test and modified Hodge test (MHT) respectively. Antibiotic susceptibility of the organisms was tested against colistin, tigecycline and 3 flouroquinolones.
The result shows that 58.0% of the isolates were ESBL producers with higher percentage in K. pneumoniae (62.9%). Further, about 40.3% and 36.6% of the isolates were resistant to meropenem and imipenem respectively. However, E. coli showed higher resistance to meropenem (47.1%) while K. pneumoniae showed higher resistance to imipenem (44.4%). Co-productions of carbapenemase and ESBL were observed in both E. coli and K. pneumoniae. Carbapenemase producing isolates were more obtained from uro-pathogens and wound isolates, with almost all the cases of co-production of the β lactamases occurring in urine and cathertips isolates. Overall susceptibilities of the isolates to colistin and tigecycline were 64.6and70.0% respectively, but isolates were less susceptible to flouroquinolones.
The finding of the study therefore indicates that carbapenem resistance is mediated by carbapenemase production and or overproduction of ESBL coupled with reduced porins. Co-production of carbapenemase, MBLs and ESBLs by some of the isolates is worrisome. Susceptibility to colistin and tigecycline was still promising, but increasing resistance to flouroquinolones has been observed.
我国医院和社区中抗生素非专业使用情况持续上升，令人担忧。因此，开展了一项研究，以从尼日利亚卡诺市两家三级医院收治或就诊的患者分离株中，表型检测超广谱β-内酰胺酶（ESBL）、碳青霉烯酶、金属β-内酰胺酶及其共产生情况。
根据CLS1 2012标准，分别使用双纸片协同试验和改良Hodge试验（MHT），对总共248株大肠埃希菌和肺炎克雷伯菌进行ESBL产生和碳青霉烯酶产生的表型筛查。检测这些菌株对黏菌素、替加环素和3种氟喹诺酮类药物的抗生素敏感性。
结果显示，58.0%的分离株为ESBL产生菌，肺炎克雷伯菌中的比例更高（62.9%）。此外，分别约有40.3%和36.6%的分离株对美罗培南和亚胺培南耐药。然而，大肠埃希菌对美罗培南的耐药性更高（47.1%），而肺炎克雷伯菌对亚胺培南的耐药性更高（44.4%）。在大肠埃希菌和肺炎克雷伯菌中均观察到碳青霉烯酶和ESBL的共产生。产生碳青霉烯酶的分离株更多来自尿路病原体和伤口分离株，几乎所有β-内酰胺酶共产生的病例都发生在尿液和导尿管分离株中。分离株对黏菌素和替加环素的总体敏感性分别为64.6%和70.0%，但分离株对氟喹诺酮类药物的敏感性较低。
因此，该研究结果表明，碳青霉烯耐药性是由碳青霉烯酶产生和/或ESBL过量产生以及孔蛋白减少介导的。一些分离株同时产生碳青霉烯酶、金属β-内酰胺酶和ESBL令人担忧。对黏菌素和替加环素的敏感性仍然良好，但已观察到对氟喹诺酮类药物的耐药性增加。
