Bifidobacterium lactis XLTG11 reduces eczema and pneumonia incidence in infants and young children

Early-life gut microbiota critically shapes immune system maturation and disease susceptibility. Disruptions in microbial development are strongly linked to rising rates of allergic and infectious diseases, such as eczema and respiratory infections, in children. While probiotic interventions show promise for restoring microbial-immune homeostasis, there's a need for rigorous, strain-specific randomized trials that integrate both clinical and microbiome outcomes to validate their efficacy and mechanisms.

This randomized, double-blind, placebo-controlled trial enrolled 352 healthy infants and young children (aged <3 years). Participants were randomly assigned to receive either Bifidobacterium animalis subsp. lactis XLTG11 at 1 × 10^10 CFU/day or a placebo for 180 days. The primary outcome measured was eczema incidence. Secondary outcomes included respiratory and gastrointestinal symptoms, growth parameters, gut microbiota composition via 16S rRNA gene sequencing, and gut immune biomarkers.

Children receiving XLTG11 demonstrated a significantly lower incidence of eczema (p=0.017) and erythema (p=0.028) compared to the placebo group. Notably, there was also a reduced incidence of physician-confirmed pneumonia in the probiotic group. Probiotic supplementation also improved stool consistency (p=0.018) without negatively impacting growth parameters.

Children receiving XLTG11 showed significantly lower incidence of eczema (p=0.017) and physician-confirmed pneumonia (RR=0.40, 95% CI 0.17-0.94; p=0.030) compared with placebo. 16S rRNA gene sequencing revealed that XLTG11 enriched beneficial gut bacteria, specifically Faecalibacterium and Akkermansia, along with other short-chain fatty acid-producing taxa. Concurrently, it suppressed potentially pathogenic genera like Helicobacter and Citrobacter. Functional profiling suggested an enrichment of pathways related to energy metabolism, vitamin biosynthesis, and the production of antimicrobial peptides (DEFB2, LL-37), alongside the preservation of secretory IgA levels, indicating enhanced gut barrier and immune function.