Department of Pediatrics, Division of Neonatology, Louisiana State University Health Sciences Center, New Orleans, LA 70118, USA.
J Pediatr Gastroenterol Nutr. 2013 Apr;56(4):397-400. doi: 10.1097/MPG.0b013e318282a8c2.
Bacterial colonization is considered a major risk factor for necrotizing enterocolitis (NEC). The objective of the present study was to test the hypothesis that histamine-2 receptor (H2-) blockers alter colonic bacterial colonization by analyzing and comparing the fecal microbiota in premature infants with and without H2-blocker therapy using sensitive molecular biological techniques.
Seventy-six premature infants ≤1500 g or <34 weeks gestation were enrolled in this case-controlled, cross-sectional study. Stool samples were collected from 25 infants receiving H2-blockers and 51 babies who had never received them. Following DNA extraction and PCR amplification of 16S rRNA, 454 pyrosequencing was undertaken and the resulting sequences were subjected to comparison with published sequence libraries.
Proteobacteria and Firmicutes were the major phyla contributing to fecal microbial communities. Microbial diversity was lower, relative abundance of Proteobacteria (primarily of the family Enterobacteriaceae) was increased, whereas that of Firmicutes was decreased in the stools of infants receiving H2-blockers compared with those who had never received them.
Although not designed to look specifically at the effect of H2-blockers on the incidence of NEC, our study suggests that their use lowers fecal microbial diversity and shifts the microfloral pattern toward Proteobacteria. These alterations in fecal microbiota may predispose the vulnerable immature gut to necrotizing enterocolitis and suggest prudence in the use of H2-blockers in the premature infant.
细菌定植被认为是坏死性小肠结肠炎（NEC）的一个主要危险因素。本研究旨在通过分析和比较接受和未接受 H2 受体阻滞剂治疗的早产儿粪便微生物群，检验组胺-2 受体（H2-）阻滞剂通过改变结肠细菌定植的假设。
本病例对照、横断面研究纳入了 76 名体重≤1500g 或胎龄<34 周的早产儿。从 25 名接受 H2 受体阻滞剂治疗的婴儿和 51 名从未接受过此类治疗的婴儿中采集粪便样本。提取 DNA 并扩增 16S rRNA 后，采用 454 焦磷酸测序，并将所得序列与已发表的序列文库进行比较。
变形菌门和厚壁菌门是粪便微生物群落的主要门。与从未接受过 H2 受体阻滞剂治疗的婴儿相比，接受 H2 受体阻滞剂治疗的婴儿粪便中微生物多样性较低，变形菌门（主要为肠杆菌科）相对丰度增加，而厚壁菌门减少。
尽管本研究并非专门观察 H2 受体阻滞剂对 NEC 发生率的影响，但我们的研究表明，H2 受体阻滞剂的使用降低了粪便微生物多样性，并使微生物群模式向变形菌门转移。粪便微生物群的这些改变可能使脆弱的未成熟肠道易发生坏死性小肠结肠炎，并提示在早产儿中谨慎使用 H2 受体阻滞剂。
