Legese Melese Hailu, Weldearegay Gebru Mulugeta, Asrat Daniel
Department of Clinical Laboratory Sciences, School of Allied Health Sciences.
Department of Microbiology, Immunology and Parasitology, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
Infect Drug Resist. 2017 Jan 25;10:27-34. doi: 10.2147/IDR.S127177. eCollection 2017.
Infections by extended-spectrum beta-lactamase- (ESBL) and carbapenem-resistant (CRE) are an emerging problem in children nowadays. Hence, the aim of this study was to determine the prevalence of ESBL- and carbapenemase-producing among children suspected of septicemia and urinary tract infections (UTIs).
A cross-sectional study was conducted from January to March 2014. A total of 322 study participants suspected of septicemia and UTIs were recruited. All blood and urine samples were cultured on blood and MacConkey agar. All positive cultures were characterized by colony morphology, Gram stain, and standard biochemical tests. Antimicrobial susceptibility test was performed on Muller-Hinton agar using disk diffusion. ESBL was detected using combination disk and double-disk synergy methods, and the results were compared. Carbapenemase was detected by modified Hodge method using meropenem. Data were analyzed using SPSS version 20.
The overall prevalence of ESBL- and carbapenemase-producing was 78.57% (n=22/28) and 12.12%, respectively. Among the tested, (84.2%, n=16/19), (100%, n=5/5), and (100%, n=1/1) were positive for ESBL. Double-disk synergy method showed 90.9% sensitivity, 66.7% specificity, 95.2% positive predictive value, and 50% negative predictive value. Carbapenemase-producing were (9.09%, n=3/33) and (3.03%, n=1/33).
Screening for ESBL production is essential for better antibiotics selection and preventing its further emergence and spread. In resource-limited settings, double-disk synergy method can be implemented for screening and confirming ESBL production. Moreover, occurrence of CRE in countries where no carbapenems are sold is worrying microbiologists as well as clinicians. Hence, identifying factors that induce carbapenemase production in the absence of carbapenems prescription is essential for control of CRE dissemination within the community.
产超广谱β-内酰胺酶（ESBL）和耐碳青霉烯类（CRE）感染如今在儿童中已成为一个新出现的问题。因此，本研究的目的是确定疑似败血症和尿路感染（UTIs）儿童中产ESBL和碳青霉烯酶的发生率。
于2014年1月至3月进行了一项横断面研究。共招募了322名疑似败血症和UTIs的研究参与者。所有血液和尿液样本均在血琼脂和麦康凯琼脂上培养。所有阳性培养物通过菌落形态、革兰氏染色和标准生化试验进行鉴定。使用纸片扩散法在Muller-Hinton琼脂上进行药敏试验。使用复合纸片法和双纸片协同法检测ESBL，并比较结果。使用美罗培南通过改良Hodge法检测碳青霉烯酶。使用SPSS 20版对数据进行分析。
产ESBL和碳青霉烯酶的总体发生率分别为78.57%（n = 22/28）和12.12%。在检测的菌株中，大肠埃希菌（84.2%，n = 16/19）、肺炎克雷伯菌（100%，n = 5/5）和奇异变形杆菌（100%，n = 1/1）的ESBL检测呈阳性。双纸片协同法显示敏感性为90.9%，特异性为66.7%，阳性预测值为95.2%，阴性预测值为50%。产碳青霉烯酶的菌株为肺炎克雷伯菌（9.09%，n = 3/33）和大肠埃希菌（3.03%，n = 1/33）。
筛查产ESBL菌株对于更好地选择抗生素以及预防其进一步出现和传播至关重要。在资源有限的环境中，双纸片协同法可用于筛查和确认产ESBL情况。此外，在未销售碳青霉烯类药物的国家出现CRE，这令微生物学家和临床医生担忧。因此，确定在未开具碳青霉烯类药物处方的情况下诱导碳青霉烯酶产生的因素对于控制社区内CRE的传播至关重要。
