Department of Microbiology, University College of Medical Sciences & Guru Teg Bahadur Hospital, Delhi, India.
Department of Paediatrics, University College of Medical Sciences & Guru Teg Bahadur Hospital, Delhi, India.
Indian J Med Res. 2017 Apr;145(4):551-557. doi: 10.4103/ijmr.IJMR_25_15.
BACKGROUND & OBJECTIVES: Multidrug-resistant enteropathogenic Escherichia coli (EPEC) is responsible for a large number of cases of infantile diarrhoea in developing countries, causing failure in treatment with consequent health burden and resulting in a large number of deaths every year. This study was undertaken to determine the proportion of typical and atypical EPEC in under five children with diarrhoea and controls, their function as a carriage and to identify virulent genes associated with them.
During the study period, 120 stool samples including 80 from controls children were collected and analyzed for the presence of EPEC using standard bacteriological methods. Isolates were subjected to antimicrobial testing by disc diffusion method. Isolates confirmed as E. coli by phenotypic method were further tested for the presence of attaching and effacing (eae) and bundle-forming pilus (bfpA) genes by real-time SYBR Green-based polymerase chain reaction.
All isolates were tested for the presence of EPEC. The frequency of typical EPEC was 20 and 16.25 per cent whereas the frequency of atypical EPEC strains was 5 and 23.75 per cent in patients and controls, respectively (PbfpA was seen in 45 and 18.75 per cent isolates of diarrhoeal patients and controls, respectively.
INTERPRETATION & CONCLUSIONS: Our results showed that typical EPEC was a common cause of diarrhoea, but at the same time, atypical EPEC was emerging as colonizers in the intestine of children with and without diarrhoea in and around Delhi. Children can be considered asymptomatic carriers of these pathogens and can transmit them to other susceptible children. Adequate steps need to be taken to stop these strains from developing and spreading further.
多重耐药性肠致病性大肠杆菌(EPEC)是发展中国家婴幼儿腹泻的主要病因之一,导致治疗失败,从而带来健康负担,并导致每年大量死亡。本研究旨在确定五岁以下腹泻儿童和对照儿童中典型和非典型 EPEC 的比例、它们作为携带菌的作用,并鉴定与其相关的毒力基因。
在研究期间,收集了 120 份粪便样本,包括 80 份对照儿童的样本,使用标准细菌学方法检测 EPEC 的存在。采用纸片扩散法进行分离物的抗菌药物敏感性测试。通过表型方法确认的大肠杆菌分离物进一步通过实时 SYBR Green 聚合酶链反应检测粘附和破坏(eae)和束形成菌毛(bfpA)基因的存在。
所有分离物均进行了 EPEC 的检测。患者和对照组中典型 EPEC 的频率分别为 20%和 16.25%,而非典型 EPEC 菌株的频率分别为 5%和 23.75%(PbfpA 分别见于 45%和 18.75%的腹泻患者和对照组分离物中。
我们的结果表明,典型 EPEC 是腹泻的常见病因,但同时,非典型 EPEC 作为一种在德里及其周边地区有和无腹泻的儿童肠道中的定植菌正在出现。儿童可被视为这些病原体的无症状携带者,并可将其传播给其他易感儿童。需要采取充分的措施来阻止这些菌株的发展和进一步传播。