目的　初步探讨粪便自诱导分子-2（AI-2）监测新生儿坏死性小肠结肠炎（NEC）病情变化的价值。方法　以 2017年10月至2018年4月收治的12例NEC患儿为研究对象，并按照胎龄、日龄、生产方式、喂养方式、抗生素使用等选择 12例与NEC组患儿匹配的非NEC新生儿为对照组。NEC诊断时定为急性期，再次开奶3天后定为恢复期。采集NEC急性期、 恢复期和对照组的粪便标本，以BB170生物荧光检测法检测粪便AI-2浓度，采用16s rDNA 高通量测序分析粪便菌群。结 果　在菌门水平，拟杆菌门比例在NEC组急性期、恢复期和对照组之间差异有统计学意义（P<0.05），其中NEC恢复期比 例最低。在菌属水平，肠球菌属、拟杆菌属比例在三组之间差异均有统计学意义（P<0.05），其中NEC急性期肠球菌属比 例最低，恢复期拟杆菌属比例最低。三组粪便AI-2浓度差异有统计学意义（P<0.05），以NEC急性期为最低。结论　AI-2 在监测NEC病情变化方面具有潜在临床应用价值。

Objective　To explore the significance of fecal autoinducer-2 (AI-2) in monitoring the occurrence and recovery of neonatal necrotizing enterocolitis (NEC). Methods　Twelve newborns with NEC, diagnosed between October 2017 to April 2018, were included in the present study (the NEC group, n=12). Another 12 newborns were paired with gestational age, age, way of delivery, way of feeding, use of antibiotics and so on, to the NEC group as control group (n=12). The onset of NEC was defined as acute phase and the recovery phase was recognized from the third day after re-introducing feeding of milk. Fecal samples from control group, NEC acute phase and NEC recovery phase were collected. The AI-2 concentration in feces was detected by biofluorescence assay. The fecal flora was analyzed by 16S rDNA high-throughput sequencing. Results　Intestinal flora in Phylum level, the Bacteroides in the acute phase of NEC was significantly lower than that in the control group (P < 0.05). The Bacteroides abundance of NEC in the recovery phase was further lower than that in the acute phase (P < 0.05). In the generic level, Enterococcus and Bacteroides decreased significantly in acute phase of NEC than that in the control group and the recovery phase of NEC (P < 0.05). There was no significant difference in Shannon index among groups. Relative biofluorescence values of feces AI-2 in acute phase of NEC was lower than those in recovery phase of NEC and control groups (P < 0.05). Conclusion　AI-2 has a strong correlation with the changes of NEC and intestinal flora disorders, which may have potential clinical value in monitoring the occurrence and recovery of NEC.