转送母乳细菌培养结果的初步分析

A pilot study on bacterial culture results of expressed breast milk

摘要:

目的本研究旨在对转送母乳的细菌培养结果进行初步分析。方法将2014年5月至2015年4月期间1178例住院新生儿,按照胎龄分为早产儿组(胎龄<37周, n=615)及足月儿组(胎龄37~42周,n=563)。采集所有患儿的初次转送至病房的母乳样本5 mL进行培养,检测母乳样本中的细菌计数及种类。结果1178例母乳样本中,菌落计数情况在早产儿组及足月儿组间比较差异无统计学意义(P>0.05)。共有55份样本(4.67%)检出潜在肠道致病菌,早产儿组与足月儿组的母乳样本潜在肠道致病菌检出率比较差异无统计学差异(P>0.05)。33例患儿进行了母乳再次采集培养,仅有10份(30%)母乳样本与第一次培养结果相同。在检出潜在肠道致病菌的55份母乳样本中,细菌计数 ≥ 105 CFU/mL的发生率(43.64%)高于未检出潜在肠道致病菌的母乳样本(14.87%)。而患儿住院期间感染的发生与母乳中是否含有潜在致病菌之间并无明确相关(P>0.05)。结论母乳并非无菌,且细菌种类并非一成不变。随机的母乳细菌培养并不能揭示母乳中细菌的情况,亦不能作为感染发生的预警信号。

Abstract:

Objective To study the bacterial culture results of expressed breast milk. Methods A total of 1178 expressed breast milk samples were collected for bacterial culture. The breast milk sampled from the mothers of preterm neonates (n=615) and term neonates (n=563) who were hospitalized between May 2014 and April 2015. Results There was no significant difference in bacterial counts between the preterm and term sample groups (P>0.05). Potential intestinal pathogens were found in 55 samples (4.63%) of the 1178 samples, with no significant difference between the preterm and term sample groups (P>0.05). The second expressed milk samples from 33 mothers were cultured. Only 10 samples (30%) were found to have the same bacteria as the first time. The detection rate of bacterial load of ≥ 105 CFU/mL was higher in those samples with potential intestinal pathogens, as compared with those samples without potential intestinal pathogens (43.64% vs 14.87%; P<0.05). There was no correlation between the incidence of neonatal infections and potential intestinal pathogens in breast milk. Conclusions Breast milk is not sterile. Bacterial loads and phylotypes are variable. Random breast milk cultures can neither describe bacterial colonies in breast milk, nor be a predictor of neonatal infection.