Background: The increasing incidence of pediatric food allergy (FA) drives an imperative for mechanistically driven risk stratification beyond descriptive diagnostics. The current systematic review aims to assess the predictive and diagnostic value of early-life non-invasive biomarkers: cord blood IgE (CS-IgE), fecal calprotectin (FC), fecal zonulin (FZ) and secretory IgA (SIgA). Methods: In accordance with the PRISMA guidelines, we performed a systematic literature search on PubMed/MEDLINE and Scopus for English observational studies published in 2009–2025. The titles and abstracts were screened by two independent reviewers and methodological quality was assessed using the Newcastle–Ottawa Scale (NOS). Results: A total of 17 studies met the inclusion criteria. This synthesis demonstrates that CS-IgE reflects a systemic atopic predisposition rather than serving as a highly sensitive predictor for isolated FA. Fecal calprotectin was the most consistent marker of inflammatory activity in non-IgE-mediated food allergies, with median values in food allergy ranging from approximately 200 to 410 µg/g and proven useful in dietary monitoring. Fecal zonulin reflects epithelial barrier dysfunction; however, its clinical utility is limited by suboptimal assay specificity. SIgA primarily reflects mucosal immune maturation and tolerance development rather than serving as a direct diagnostic marker. Conclusions: Although CS-IgE, FC, FZ and SIgA exhibit potential in the risk stratification of early FA, their clinical implementation is complicated by methodological heterogeneity and concerns regarding analytical specificity, especially with respect to zonulin assays. We propose an integrated multi-biomarker risk stratification model as a conceptual hypothesis requiring prospective validation in future large-scale studies.

Co-exposure to airborne pollen and fungal spores is increasingly recognized as a contributor to asthma and allergic rhinitis, especially as climatic shifts since 2020 have intensified their seasonal overlap. We systematically searched PubMed and Google Scholar for studies published between 2020 and 2025 that assessed simultaneous pollen–fungi exposure and respiratory outcomes. Screening was performed independently by two reviewers, resulting in 12 eligible studies out of 320 records. Meta-analysis was not feasible due to substantial heterogeneity in exposure definitions, taxa, outcome measures, and analytical approaches. Overall, the studies indicate that short-term co-exposure tends to worsen respiratory symptoms and increase emergency visits or asthma exacerbations, with stronger effects in children, polysensitized individuals, and urban settings. However, effect sizes varied considerably across regions and methodologies. Environmental and climatological papers provided context for seasonal overlap but did not contribute clinical data. Current evidence suggests a potential synergistic effect, though more standardized exposure metrics are needed to refine risk estimates.