The dramatic global rise in pediatric allergic diseases, including atopic dermatitis, food allergy, allergic rhinitis, and asthma, has coincided with alterations in the human microbiome, attributed to factors such as increased antibiotic use, dietary changes, and urbanization. This has propelled the hypothesis that early-life microbial dysbiosis is a pivotal factor in immune dysregulation and the subsequent development of allergic sensitization. Consequently, microbiome-targeted therapies, primarily probiotics, prebiotics, synbiotics, and postbiotics, have emerged as promising strategies for primary and secondary allergy prevention. This critical review synthesizes and evaluates the current evidence from clinical trials, meta-analyses, and mechanistic studies on these interventions. While certain strains, particularly Lactobacillus rhamnosus GG and combinations thereof, show promise in specific contexts like eczema prevention, the overall evidence remains heterogeneous, strain-specific, and condition-dependent. Significant gaps persist regarding optimal strains, timing, duration, and mechanisms of action. Furthermore, emerging therapies like fecal microbiota transplantation (FMT) and precise microbial consortia are explored. This review concludes that while the microbiome is a legitimate therapeutic target, current recommendations must be cautious and personalized. Future research must prioritize well-designed, longitudinal studies integrating deep multi-omics profiling to move from association to causation and develop effective, safe, and standardized microbiome-based interventions for pediatric allergy prevention.

Microbiome, Dysbiosis, Probiotics

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