The study was published recently in the journal Gut Microbes. It was performed by researchers associated with universities and a hospital in Maastricht, Netherlands and Aachen, Germany.
NEC poses grave threat to preemies
The researchers noted that oral administration of probiotics for premature infants has been recommended for years to forestall the development of NEC, or necrotizing enterocolitis. Neonates are highly susceptible to this condition in which the intestinal wall, usually in the colon, becomes inflamed and may even break down and allow gut bacteria to enter the abdominal cavity, leading to an infection which can be fatal. According a 2011 paper in the New England Journal of Medicine, the prevalence of this condition has not changed over recent decades and may even be getting worse, as new treatments and technology allow ever smaller (and thus more vulnerable) babies to survive.
The paper pegged the prevalence of NEC at about 7% among infants that weighed between 500 grams and 1,500 grams at birth. The risk of death stands as high as 30%, and babies that survive are under greater risk of neurodevelopmental delays or other health problems.
Probiotics shown to help, but exactly what are they doing?
While the use of probiotics has shown promise in this area, the authors said much less is known about how the probiotics are actually achieving these results. The authors sought to answer the question of how the gut makeup of these infants actually changes with probiotic administration.
The researchers took weekly fecal samples from 80 preterm infants born at less than 32 weeks of gestation (normal gestation is 38 to 42 weeks). In all 174 samples were analyzed. The infants were all born and treated at the Aachen University Hospital between January 2016 and January 2018. The hospital was routinely treating preemies with a probiotic formulation at the beginning of the study but had to switch to another during the study period because the first formulation was no longer commercially available. An interregnum ensued before a new probiotic intervention was selected, during which time neonates treated at the hospital received no probiotics. So the study ended up being divided into three groups in this way.
One of the probiotic interventions consisted of Lactobacillus acidophilus (ATCC 4356) and Bifidobacterium longum subspecies infantis (ATCC 15697). The second probiotic was a mixture of Lactobacillus acidophilus La-14 (ATCC SD5212), Bifidobacterium longum subsp. longum Bl-05 (ATCC SD5588), Lactobacillus casei Lc-11 (ATCC SD5213), and Bifidobacterium animalis subsp. lactis (ATCC SD5215).
The three groups of infants were similar in gestational age, weight and in demographic makeup. Most of the babies were born via Caesarean section. The infants receiving probiotics were treated up to the age of 36 weeks.
Probiotics smooth out ‘bumps,’ tamp down problem species
The researchers found that the babies receiving probiotics showed more homogeneity and consistency among their microbiome makeups than did the group that received no intervention. In particular the control group showed dynamic shifts in the abundance of bacteria in the Enterococcus, Escherichia, and Klebsiella genuses.
Among the probiotic groups the researchers found that the probiotic organisms successfully colonized the infants’ guts in a transient fashion, and also significantly altered the makeup of the microbiome as a whole.
Probiotic supplementation was associated with lower temporal variation as well as higher relative abundance of Bifidobacterium and Enterobacter combined with reduced abundance of Escherichia, Enterococcus, and Klebsiella,” the authors noted.
“Our results demonstrate successful transient colonization by probiotic bacteria and a significant influence on the endogenous microbiota with a reduced abundance of bacterial taxa associated with the development of NEC. These results emphasize that probiotic supplementation may allow targeted manipulation of the enteric microbiota and confer a clinical benefit,” they concluded.
Sanders: Results add to understanding of how probiotics work to combat NEC
Mary Ellen Sanders, PhD, said the study in an important step in more fully understanding what probiotic supplementation is doing in the guts of preemies. Sanders is an industry consultant and the executive science director for the International Scientific Association for Probiotics and Prebiotics (ISAPP).
“Current evidence that certain probiotics can improve outcomes for premature infants by reducing morbidity and mortality associated with NEC is actionable. However, the mechanisms for this clinical effect are not clear. This paper documents probiotic-induced microbiota shifts—including higher relative abundance of Bifidobacterium—that may account for observed clinical effects. These studies are important to better refine the best clinical approach to use of probiotics to prevent NEC,” Sanders said.
Source: Gut Microbes
Influence of probiotic supplementation on the developing microbiota in human preterm neonates
Authors: Van Best N, et al.