刚果民主共和国儿童血便分离的非伤寒沙门氏菌具有高度遗传相似性。
High genetic similarity between non-typhoidal Salmonella isolated from paired blood and stool samples of children in the Democratic Republic of the Congo.
机构信息
Department of Microbiology, Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo.
Department of Microbiology, University Hospital of Kinshasa, Democratic Republic of the Congo.
出版信息
PLoS Negl Trop Dis. 2020 Jul 2;14(7):e0008377. doi: 10.1371/journal.pntd.0008377. eCollection 2020 Jul.
BACKGROUND
Non-typhoidal Salmonella (NTS) serotypes Typhimurium and Enteritidis are a major cause of bloodstream infections in children in sub-Saharan Africa but their reservoir is unknown. We compared pairs of NTS blood and stool isolates (with the same NTS serotype recovered in the same patient) for genetic similarity.
METHODS
Between November 2013 and April 2017, hospital-admitted children (29 days to 14 years) with culture-confirmed NTS bloodstream infections were enrolled in a cross-sectional study at Kisantu Hospital, DR Congo. Stool cultures for Salmonella were performed on a subset of enrolled children, as well as on a control group of non-febrile hospital-admitted children. Pairs of blood and stool NTS isolates were assessed for genetic similarity by multiple-locus variable-number of tandem repeats (MLVA) and genomics analysis.
RESULTS
A total of 299 children with NTS grown from blood cultures (Typhimurium 68.6%, Enteritidis 30.4%, other NTS 1.0%) had a stool sample processed; in 105 (35.1%) of them NTS was detected (Typhimurium 70.5%, Enteritidis 25.7%, other NTS 3.8%). A total of 87/105 (82.9%) pairs of blood and stool NTS isolates were observed (representing 29.1% of the 299 children). Among 1598 controls, the proportion of NTS stool excretion was 2.1% (p < 0.0001). MLVA types among paired isolates were identical in 82/87 (94.3%) pairs (27.4% of the 299 children; 61/66 (92.4%) in Typhimurium and 21/21 (100%) in Enteritidis pairs). Genomics analysis confirmed high genetic similarity within 41/43 (95.3%) pairs, showing a median SNP difference of 1 (range 0-77) and 1 (range 0-4) for Typhimurium and Enteritidis pairs respectively. Typhimurium and Enteritidis isolates belonged to sequence types ST313 lineage II and ST11 respectively.
CONCLUSION
Nearly 30% of children with NTS bloodstream infection showed stool excretion of an NTS isolate with high genetic similarity, adding to the evidence of humans as a potential reservoir for NTS.
背景
非伤寒型沙门氏菌（NTS）血清型鼠伤寒和肠炎是撒哈拉以南非洲儿童血流感染的主要原因，但它们的储存宿主尚不清楚。我们比较了 NTS 血液和粪便分离株（在同一患者中同一 NTS 血清型的恢复）的遗传相似性。
方法
2013 年 11 月至 2017 年 4 月，刚果民主共和国基桑图医院对确诊为 NTS 血流感染的住院患儿（29 天至 14 岁）进行了一项横断面研究。对纳入的部分患儿和非发热住院患儿进行粪便培养以检测沙门氏菌。通过多位点可变数量串联重复（MLVA）和基因组分析评估血液和粪便 NTS 分离株的遗传相似性。
结果
299 例血液培养中生长出 NTS（鼠伤寒 68.6%，肠炎 30.4%，其他 NTS 1.0%）的患儿中有 291 例进行了粪便处理；其中 105 例（35.1%）粪便中检测到 NTS（鼠伤寒 70.5%，肠炎 25.7%，其他 NTS 3.8%）。87/105（82.9%）对血液和粪便 NTS 分离株观察到匹配（占 299 例患儿的 29.1%）。在 1598 名对照中，NTS 粪便排出率为 2.1%（p<0.0001）。1598 名对照中，NTS 粪便排出率为 2.1%（p<0.0001）。配对分离株的 MLVA 类型在 82/87（94.3%）对（占 299 例患儿的 27.4%；61/66[92.4%]在鼠伤寒和 21/21[100%]在肠炎对）中相同。基因组分析证实，41/43（95.3%）对具有高度遗传相似性，鼠伤寒和肠炎对分别显示中位数 SNP 差异为 1（范围 0-77）和 1（范围 0-4）。鼠伤寒和肠炎分离株分别属于序列型 ST313 谱系 II 和 ST11。
结论
近 30%的 NTS 血流感染患儿粪便中排出具有高度遗传相似性的 NTS 分离株，这进一步证明人类可能是 NTS 的潜在储存宿主。
Zotero 插件