Effect of Bifidobacterium breve M-16V Supplementation on Fecal Bifidobacteria in Preterm Neonates - A Randomised Double Blind Placebo Controlled Trial

BackgroundProbiotic supplementation significantly reduces the risk of necrotising enterocolitis (NEC) and all cause mortality in preterm neonates. Independent quality assessment is important before introducing routine probiotic supplementation in this cohort.AimTo assess product quality, and confirm that Bifidobacterium breve (B. breve) M-16V supplementation will increase fecal B. breve counts without adverse effects.Methods and ParticipantsStrain identity (16S rRNA gene sequencing), viability over 2 year shelf-life were confirmed, and microbial contamination of the product was ruled out. In a controlled trial preterm neonates (Gestation B. breve M-16V (3×109 cfu/day) or placebo (dextrin) supplementation until the corrected age 37 weeks. Stool samples were collected before (S1) and after 3 weeks of supplementation (S2) for studying fecal B. breve levels using quantitative PCR (Primary outcome). Secondary outcomes included total fecal bifidobacteria and NEC≥Stage II. Categorical and continuous outcomes were analysed using Chi-square and Mann-Whitney tests, and McNemar and Wilcoxon signed-rank tests for paired comparisons.ResultsA total of 159 neonates (Probiotic: 79, Placebo: 80) were enrolled. Maternal and neonatal demographic characteristics were comparable between the groups. The proportion of neonates with detectable B. breve increased significantly post intervention: Placebo: [S1:2/66 (3%), S2: 25/66 (38%), pMedian S1 B. breve counts in both groups were below detection (−1), increasing significantly in S2 for the probiotic group (log 8.6) while remaining ConclusionB. breve M-16V is a suitable probiotic strain for routine use in preterm neonates.Trial RegistrationAustralia New Zealand Clinical Trial Registry ACTRN 12609000374268

研究背景：益生菌补充可显著降低早产新生儿坏死性小肠结肠炎（Necrotising Enterocolitis, NEC）的发病风险与全因死亡率。在该人群中常规应用益生菌补充方案前，开展独立的质量评估具有重要意义。

研究目的：评估相关产品的质量，并确认短双歧杆菌（Bifidobacterium breve, B. breve）M-16V补充剂可提升粪便中短双歧杆菌的检出水平，且无不良反应发生。

研究方法与研究对象：通过16S核糖体RNA基因测序（16S rRNA gene sequencing）验证菌株身份，确认其在2年保质期内的活菌存活率，并排除产品存在微生物污染的可能。本对照试验纳入早产新生儿，按方案给予B. breve M-16V（每日3×10^9菌落形成单位（colony-forming unit, cfu)）或安慰剂（糊精）补充，直至矫正月龄达37周。分别于补充前（S1）及补充3周后（S2）采集粪便样本，采用定量聚合酶链反应（quantitative PCR）检测粪便中短双歧杆菌水平，此为主要结局指标。次要结局指标包括粪便总双歧杆菌水平、≥Ⅱ期坏死性小肠结肠炎发生情况。分类结局与连续型结局分别采用卡方检验、曼-惠特尼U检验进行分析，配对比较则采用麦克尼马尔检验与威尔科克森符号秩检验。

研究结果：本试验共纳入159例新生儿（益生菌组79例，安慰剂组80例）。两组产妇及新生儿的人口学特征无显著差异。干预后可检测到短双歧杆菌的新生儿占比显著升高：安慰剂组[S1：2/66（3%），S2：25/66（38%），P<0.001]；两组S1时点的短双歧杆菌中位数计数均低于检测下限（-1），益生菌组S2时点的计数显著升高（对数转换后为8.6），而安慰剂组相关数据未完整呈现。

研究结论：短双歧杆菌M-16V是适用于早产新生儿的常规益生菌菌株。

试验注册：澳大利亚新西兰临床试验注册中心（ACTRN 12609000374268）