Abstract：
BACKGROUND: Necrotizing enterocolitis is the most severe life-threatening acquired gastrointestinal disorder among preterm neonates. We describe here an outbreak of Clostridium butyricum-related necrotizing enterocolitis in preterm neonates that occurred in three different neonatal centres, in southeast France.
METHODS: We defined a confirmed case of C. butyricum-related necrotizing enterocolitis in preterm neonates by the presence of clinical signs according to modified Bell criteria and C. butyricum identified from stool samples using real-time polymerase chain reaction or culture. A phylogenetic analysis of the isolated strains by whole-genome sequencing was also performed.
RESULTS: Between 5th and 27th January 2022, we identified 10 confirmed cases of C. butyricum-related necrotizing enterocolitis, including five from Neonatal Centre 1, four from Neonatal Centre 2, and one from Neonatal Centre 3. The attack rate of necrotizing enterocolitis in Neonatal Centre 1 was 7.1% (5/70). The positivity rate of C. butyricum detected from stool samples was higher during the outbreak period (37/276; 13.4%) than outside this period (7/369; 1.9%), while systematic screening was maintained (P<0.001). Phylogenetic analysis showed a clonality between strains inside four clusters. Two clusters included neonates hospitalized in different neonatal centres, suggesting the transmission of C. butyricum strains during the transfer of neonates between neonatal centres.
CONCLUSIONS: This outbreak of C. butyricum-related necrotizing enterocolitis confirms a cross-transmission between preterm neonates, including twin or triplet siblings, and involving necrotizing enterocolitis cases together with asymptomatic carriers. After three months of follow-up, no further cases were identified following the implementation of contact precautions with sporicidal agents.
METHODS: We defined a confirmed case of C. butyricum-related necrotizing enterocolitis in preterm neonates by the presence of clinical signs according to modified Bell criteria and C. butyricum identified from stool samples using real-time polymerase chain reaction or culture. A phylogenetic analysis of the isolated strains by whole-genome sequencing was also performed.
RESULTS: Between 5th and 27th January 2022, we identified 10 confirmed cases of C. butyricum-related necrotizing enterocolitis, including five from Neonatal Centre 1, four from Neonatal Centre 2, and one from Neonatal Centre 3. The attack rate of necrotizing enterocolitis in Neonatal Centre 1 was 7.1% (5/70). The positivity rate of C. butyricum detected from stool samples was higher during the outbreak period (37/276; 13.4%) than outside this period (7/369; 1.9%), while systematic screening was maintained (P<0.001). Phylogenetic analysis showed a clonality between strains inside four clusters. Two clusters included neonates hospitalized in different neonatal centres, suggesting the transmission of C. butyricum strains during the transfer of neonates between neonatal centres.
CONCLUSIONS: This outbreak of C. butyricum-related necrotizing enterocolitis confirms a cross-transmission between preterm neonates, including twin or triplet siblings, and involving necrotizing enterocolitis cases together with asymptomatic carriers. After three months of follow-up, no further cases were identified following the implementation of contact precautions with sporicidal agents.
摘要：
背景：坏死性小肠结肠炎是早产儿中最严重的危及生命的获得性胃肠道疾病。我们在这里描述了在三个不同的新生儿中心发生的早产新生儿中的丁酸梭菌相关坏死性小肠结肠炎的爆发。在法国东南部。
方法：我们根据改良的Bell标准定义了一例确诊的早产儿丁酸梭菌相关性坏死性小肠结肠炎的病例，并使用实时聚合酶链反应或培养从粪便样本中鉴定出丁酸梭菌。还通过全基因组测序对分离的菌株进行了系统发育分析。
结果：在2022年1月5日至27日之间，我们确定了10例与丁酸梭菌相关的坏死性小肠结肠炎的确诊病例，包括五个来自新生儿中心1，四个来自新生儿中心2，一个来自新生儿中心3。新生儿中心1的坏死性小肠结肠炎发病率为7.1%(5/70)。在爆发期间，从粪便样本中检测到的丁酸梭菌阳性率（37/276;13.4％）高于此期间以外（7/369;1.9％），同时保持系统筛查（P<0.001）。系统发育分析表明，四个簇内的菌株之间存在克隆性。两组包括在不同新生儿中心住院的新生儿,提示在新生儿中心之间转移过程中，丁酸梭菌菌株的传播。
结论：这次丁酸梭菌相关性坏死性小肠结肠炎的爆发证实了早产儿之间的交叉传播，包括双胞胎或三胞胎兄弟姐妹，涉及坏死性小肠结肠炎病例和无症状携带者。经过三个月的随访，在实施与杀孢子剂的接触预防措施后,未发现其他病例.
方法：我们根据改良的Bell标准定义了一例确诊的早产儿丁酸梭菌相关性坏死性小肠结肠炎的病例，并使用实时聚合酶链反应或培养从粪便样本中鉴定出丁酸梭菌。还通过全基因组测序对分离的菌株进行了系统发育分析。
结果：在2022年1月5日至27日之间，我们确定了10例与丁酸梭菌相关的坏死性小肠结肠炎的确诊病例，包括五个来自新生儿中心1，四个来自新生儿中心2，一个来自新生儿中心3。新生儿中心1的坏死性小肠结肠炎发病率为7.1%(5/70)。在爆发期间，从粪便样本中检测到的丁酸梭菌阳性率（37/276;13.4％）高于此期间以外（7/369;1.9％），同时保持系统筛查（P<0.001）。系统发育分析表明，四个簇内的菌株之间存在克隆性。两组包括在不同新生儿中心住院的新生儿,提示在新生儿中心之间转移过程中，丁酸梭菌菌株的传播。
结论：这次丁酸梭菌相关性坏死性小肠结肠炎的爆发证实了早产儿之间的交叉传播，包括双胞胎或三胞胎兄弟姐妹，涉及坏死性小肠结肠炎病例和无症状携带者。经过三个月的随访，在实施与杀孢子剂的接触预防措施后,未发现其他病例.
