de la Cochetiere Marie-France, Piloquet Hugues, des Robert Clotilde, Darmaun Dominique, Galmiche Jean-Paul, Roze Jean-Christophe
INSERM Unité 539, CHU Hôtel-Dieu, 44035 Nantes Cedex 1, France.
Pediatr Res. 2004 Sep;56(3):366-70. doi: 10.1203/01.PDR.0000134251.45878.D5. Epub 2004 Jun 16.
Necrotizing enterocolitis (NEC) is among the most severe conditions that can affect preterm infants. Although the etiology of NEC remains unknown, initial bacterial colonization could play a pivotal role in the development of NEC. To further explore the putative relationship between pathogen microorganisms and NEC, we conducted a prospective case-control study in 12 preterm infants with a new approach based on molecular techniques. Over an inclusion period of 24 mo, 12 neonates of <34 wk gestational age admitted to the neonatal unit were enrolled. The group included three cases of NEC, and nine control infants without evidence of NEC who were matched for gestational age and birth weight. Stool samples were collected at weekly intervals from all infants. PCR and temporal temperature gradient gel electrophoresis of 16S ribosomal DNA were used to detect the establishment of bacterial communities in the digestive tract. A salient feature of the bacteriological pattern was observed only in the three infants who later developed NEC: A band corresponding to the Clostridium perfringens subgroup could be detected in early samples, before diagnosis. There was no evidence for this specific band in any of the nine controls. To our knowledge, the current report is the first to demonstrate that the use of molecular techniques based on the study of bacterial 16S rRNA genes allowed the recognition of C. perfringens species in the first 2 wk of life of three infants who later displayed symptoms of NEC. A significant temporal relationship was thus established between early colonization by Clostridium and the later development of NEC. Compared with conventional bacteriological culturing methods, the use of this new molecular approach to analyze the gastrointestinal ecosystem should therefore allow a more complete and rapid assessment of intestinal flora. Although the current data do not constitute definitive proof that the identified bacterial species was a causative agent in the development of NEC, they outline the promise of this new technique based on molecular biology, and suggest that large-scale studies on a much wider population at high risk for NEC may be warranted.
坏死性小肠结肠炎（NEC）是影响早产儿的最严重病症之一。尽管NEC的病因尚不清楚，但初始细菌定植可能在NEC的发展中起关键作用。为了进一步探究病原微生物与NEC之间的假定关系，我们采用基于分子技术的新方法对12例早产儿进行了一项前瞻性病例对照研究。在24个月的纳入期内，招募了12名孕周小于34周且入住新生儿病房的新生儿。该组包括3例NEC患儿，以及9例无NEC证据且孕周和出生体重相匹配的对照婴儿。每周从所有婴儿收集粪便样本。使用16S核糖体DNA的PCR和时间温度梯度凝胶电泳来检测消化道中细菌群落的建立。仅在后来发生NEC的3例婴儿中观察到细菌学模式的一个显著特征：在诊断前的早期样本中可检测到一条与产气荚膜梭菌亚组相对应的条带。9例对照婴儿中的任何一例均未发现该特定条带。据我们所知，本报告首次证明，基于细菌16S rRNA基因研究的分子技术能够在3例后来出现NEC症状的婴儿出生后的前2周内识别出产气荚膜梭菌。因此，梭菌的早期定植与NEC的后期发展之间建立了显著的时间关系。与传统细菌培养方法相比，使用这种新的分子方法分析胃肠道生态系统应该能够更全面、快速地评估肠道菌群。尽管目前的数据并不构成确定所鉴定细菌物种是NEC发展中的致病因子的确凿证据，但它们概述了这种基于分子生物学的新技术的前景，并表明可能有必要对更多NEC高危人群进行大规模研究。
