Langendorf Céline, Le Hello Simon, Moumouni Aissatou, Gouali Malika, Mamaty Abdoul-Aziz, Grais Rebecca F, Weill François-Xavier, Page Anne-Laure
Epicentre, Paris, France.
Institut Pasteur, Unité des Bactéries Pathogènes Entériques, Centre National de Référence des Escherichia coli, Shigella et Salmonella, Paris, France.
PLoS One. 2015 Mar 23;10(3):e0120275. doi: 10.1371/journal.pone.0120275. eCollection 2015.
Although rotavirus is the leading cause of severe diarrhea among children in sub-Saharan Africa, better knowledge of circulating enteric pathogenic bacteria and their antimicrobial resistance is crucial for prevention and treatment strategies.
METHODOLOGY/PRINCIPAL FINDINGS: As a part of rotavirus gastroenteritis surveillance in Maradi, Niger, we performed stool culture on a sub-population of children under 5 with moderate-to-severe diarrhea between April 2010 and March 2012. Campylobacter, Shigella and Salmonella were sought with conventional culture and biochemical methods. Shigella and Salmonella were serotyped by slide agglutination. Enteropathogenic Escherichia coli (EPEC) were screened by slide agglutination with EPEC O-typing antisera and confirmed by detection of virulence genes. Antimicrobial susceptibility was determined by disk diffusion. We enrolled 4020 children, including 230 with bloody diarrhea. At least one pathogenic bacterium was found in 28.0% of children with watery diarrhea and 42.2% with bloody diarrhea. Mixed infections were found in 10.3% of children. EPEC, Salmonella and Campylobacter spp. were similarly frequent in children with watery diarrhea (11.1%, 9.2% and 11.4% respectively) and Shigella spp. were the most frequent among children with bloody diarrhea (22.1%). The most frequent Shigella serogroup was S. flexneri (69/122, 56.5%). The most frequent Salmonella serotypes were Typhimurimum (71/355, 20.0%), Enteritidis (56/355, 15.8%) and Corvallis (46/355, 13.0%). The majority of putative EPEC isolates was confirmed to be EPEC (90/111, 81.1%). More than half of all Enterobacteriaceae were resistant to amoxicillin and co-trimoxazole. Around 13% (46/360) Salmonella exhibited an extended-spectrum beta-lactamase phenotype.
This study provides updated information on enteric bacteria diversity and antibiotic resistance in the Sahel region, where such data are scarce. Whether they are or not the causative agent of diarrhea, bacterial infections and their antibiotic resistance profiles should be closely monitored in countries like Niger where childhood malnutrition pre-disposes to severe and invasive infections.
尽管轮状病毒是撒哈拉以南非洲地区儿童严重腹泻的主要病因，但更好地了解肠道致病细菌的流行情况及其抗菌耐药性对于预防和治疗策略至关重要。
方法/主要发现：作为在尼日尔马拉迪进行的轮状病毒胃肠炎监测的一部分，我们于2010年4月至2012年3月期间，对5岁以下中重度腹泻儿童的一个亚组进行了粪便培养。采用传统培养和生化方法检测弯曲杆菌、志贺氏菌和沙门氏菌。通过玻片凝集法对志贺氏菌和沙门氏菌进行血清分型。通过用肠致病性大肠杆菌（EPEC）O分型抗血清进行玻片凝集法筛选EPEC，并通过检测毒力基因进行确认。采用纸片扩散法测定抗菌药物敏感性。我们纳入了4020名儿童，其中230名有血性腹泻。在水样腹泻儿童中，28.0%至少发现一种致病细菌，在血性腹泻儿童中这一比例为42.2%。10.3%的儿童存在混合感染。在水样腹泻儿童中，EPEC、沙门氏菌和弯曲杆菌属的感染频率相似（分别为11.1%、9.2%和11.4%），而志贺氏菌属在血性腹泻儿童中最为常见（22.1%）。最常见的志贺氏菌血清群是福氏志贺氏菌（69/122，56.5%）。最常见的沙门氏菌血清型是鼠伤寒沙门氏菌（71/355，20.0%）、肠炎沙门氏菌（56/355，15.8%）和科瓦利斯沙门氏菌（46/355，13.0%）。大多数推定的EPEC分离株被确认为EPEC（90/111，81.1%）。超过一半的肠杆菌科细菌对阿莫西林和复方新诺明耐药。约13%（46/360）的沙门氏菌表现出超广谱β-内酰胺酶表型。
本研究提供了萨赫勒地区肠道细菌多样性和抗生素耐药性的最新信息，该地区此类数据匮乏。在像尼日尔这样儿童营养不良易引发严重侵袭性感染的国家，无论细菌感染是否为腹泻的病原体，都应密切监测细菌感染情况及其抗生素耐药谱。
