D2.174 - Association Between Environmental Conditions and Mold Sensitization in Children with Allergic Rhinitis and Asthma

Mold exposure has been associated with the development and exacerbation of allergic rhinitis and asthma. However, the relationship between environmental conditions and mold sensitization patterns in paediatric patients remains insufficiently defined. The aim of this study was to evaluate the association between environmental conditions and mold sensitization in children with allergic rhinitis and asthma.

This retrospective study included 250 children with allergic rhinitis and/or asthma evaluated between 2018 and 2023 who demonstrated mold sensitization. Patients were classified as having indoor, outdoor, or combined indoor and outdoor sensitization. Demographic characteristics, eosinophil counts, total IgE levels, residential area (urban/rural), and meteorological variables (humidity, temperature, wind speed, precipitation, and number of rainy days) were analyzed.

Of the 250 patients (42% female; median age 6 years), 86 (34.4%) lived in rural and 164 (65.6%) in urban areas. Concomitant asthma was present in 49.6% of patients. Indoor sensitization was detected in 35.2%, outdoor sensitization in 31.2%, and combined sensitization in 33.6%. Alternaria (38.4%) and Cladosporium (39.6%) were the most frequent indoor molds, whereas Aspergillus (38%) and Penicillium (36.4%) predominated among outdoor molds. Asthma prevalence was significantly higher in children with indoor sensitization compared to outdoor-only sensitization (p=0.04). Eosinophil counts and total IgE levels were significantly higher in patients with combined sensitization (p<0.001). Combined sensitization was more frequent among urban residents compared to rural residents. No significant association was found between mold sensitization and meteorological parameters. Indoor sensitization was significantly higher during the first 10 months of 2023 (p<0.05).

Indoor mold sensitization appears to be a significant risk factor for asthma in children with allergic rhinitis. Urban residence may increase the likelihood of combined sensitization. Larger prospective studies are needed to clarify environmental determinants of mold sensitization.