Aeroallergen sensitization, Th2-skewed systemic immunity, and severe pneumonia in hospitalized children: a retrospective cohort study
Year: 2026
Type: article
Abstract: Background Aeroallergen sensitization is common in children and is associated with a Th2-skewed immune response, but its relationship with community-acquired pneumonia (CAP) severity and systemic immune profiles remains incompletely characterized. This study compared systemic immune-inflammatory profiles and disease severity between sensitized and non-sensitized children hospitalized with CAP. Methods This retrospective cohort study included children aged 6 months to 14 years hospitalized with CAP (January 2019–December 2023). All participants had aeroallergen-specific IgE testing for six inhalant allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat dander, dog dander, Alternaria alternata, and mixed grass pollen), serum cytokine assays, (IL-2, IL-4, IL-6, IL-10, TNF-α, IFN- γ ), lymphocyte subsets, humoral immunity markers, infection biomarkers, and a respiratory nine-antibody panel. Patients were classified as sensitized or non-sensitized. Co-primary outcomes were wheezing and severe pneumonia. Multivariable logistic regression identified factors associated with severe disease. Results Of 2,351 children screened, 412 were included (median age 4.2 years; 56.3% male); 152 (36.9%) were sensitized. Excluded patients had shorter hospitalization than included patients. Sensitized children had higher rates of wheezing (46.1% vs. 20.8%, P < 0.001) and severe pneumonia (23.7% vs. 12.3%, P = 0.003). The distribution of pathogens identified by serology was similar between groups. Sensitized children had higher total IgE, IL-4, and IL-10 levels, lower IFN- γ levels, a lower IFN- γ /IL-4 ratio, and a higher CD4/CD8 ratio (all P < 0.01). In multivariable analysis, sensitization (aOR 2.08, 95% CI: 1.22–3.54), higher IL-6, and higher CD4/CD8 ratio were associated with severe CAP. Conclusions In this retrospective cohort, aeroallergen sensitization was associated with a Th2-skewed systemic cytokine profile and higher odds of severe pneumonia in children hospitalized with CAP. These associations were not explained by the pathogens identified by serology; however, the IgM panel omitted several common respiratory pathogens and has limited reliability, so definitive etiological conclusions cannot be drawn. Prospective studies with molecular diagnostics are needed to confirm these findings.
Source: Frontiers in Medicine
Authors: Yana Xu, Fangju Liao, Yu Xie
Institution: Shanghai University of Traditional Chinese Medicine
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7225619505