Probiotic Supplementation Reduces RRTIs and Enhances Gut Microbial and Immunity in Children: A Randomized Controlled Trial.

Probiotic supplementation significantly reduced the duration and frequency of fever, cough, upper respiratory tract infections, trachea/bronchitis, pneumonia, and overall RRTI recurrence compared with placebo.

• All comparisons between probiotic and placebo groups reached statistical significance (all p < 0.05)
• The intervention used two specific strains: Bifidobacterium animalis subsp. lactis XLTG11 and Lactiplantibacillus plantarum CCFM8661
• Daily supplementation was administered for 180 days
• 120 children diagnosed with RRTIs were enrolled in the trial

Gut microbiota community composition differed clearly between the probiotic and placebo groups at day 180.

• The probiotic group exhibited greater abundance of beneficial commensal taxa
• The placebo group showed higher representation of opportunistic genera
• Functional pathway analysis indicated shifts consistent with enhanced metabolic stability in probiotic recipients
• Microbiota profiling was conducted at day 180 of the intervention

Immune biomarker patterns indicated a more regulated humoral response in the probiotic group.

• The probiotic group showed comparatively stable IgG, IgM, and complement C3 levels over the intervention period
• The pattern was described as reflecting a 'more regulated humoral response' in probiotic recipients
• Immune biomarker changes were assessed over the 180-day intervention period

Probiotic supplementation demonstrated a favorable safety profile with no treatment-related adverse events reported.

• No treatment-related adverse events were reported in either group
• Growth trajectories remained normal in both the probiotic and placebo groups
• The trial was randomized, double-blind, and placebo-controlled with 120 children
• The intervention lasted 180 days

The trial was designed as a randomized, double-blind, placebo-controlled study in children diagnosed with recurrent respiratory tract infections.

• 120 children diagnosed with RRTIs were enrolled and received either probiotic or matched placebo daily
• The intervention duration was 180 days
• The two probiotic strains used were Bifidobacterium animalis subsp. lactis XLTG11 and Lactiplantibacillus plantarum CCFM8661
• Outcomes included clinical infection measures, gut microbiota profiling, functional pathway analysis, and immune biomarkers