D2.09 - Correlation Patterns Among House Dust Mite Allergens in Allergic Rhinitis: A Molecular Sensitization Study in Mallorca

The molecular characterization of house dust mite (HDM) allergens provides insight into sensitization profiles, but the relationships between different HDM allergens remain poorly understood. In this study we analyze the interrelationships between IgE levels against HDM allergens and assess their clinical significance.

A cohort of 100 patients with allergic rhinitis and confirmed sensitization to Dermatophagoides pteronyssinus was analyzed. IgE levels were measured using a singleplex and a multiplex IgE assay. Statistical correlations were assessed between IgE levels specific mite allergen components (Der p 1, Der p 2, Der p 5, Der p 7, Blo t 5, etc.). Associations with clinical and demographic variables were also evaluated.

Median Der p was 32,2 kU/L (IQR:50.25). No relevant molecular sensitization to Dermatophagoides spp. was observed in patients with Der p levels below 2 kU/L. In 59 of 60 patients with Der p levels >10 kU/L, at least one major allergen with relevant IgE levels was detected.

The highest prevalence (92/100) was observed for Der p 1, although its median levels were low (3.19 kU/L, IQR: 8.18). Conversely, Der f 2 had the highest median IgE levels (23.4 kU/L; IQR: 33.74). Multivariate analyses of allergen levels are shown in Table. Some mite allergen sensitizations could be predicted through clusters of other mite allergens (see Figure).

HDM IgE levels positively correlated with the number of HDM sensitizations for Aca s (r=0.44), Blo t (r=0.48), Blo t 10 (r=0.21), Blo t 21 (r=0.43), Der f 1 (r=0.49), Der f 2 (r=0.65), Der p 1 (r=0.50), Der p 2 (r=0.64), Der p 5 (r=0.51), and Der p 7 (r=0.44).

HDM IgE levels were negatively associated with age (Aca s, Der f 1/2, Der p (CAP), Der p 1/2/5/7/21/23, Gly d 2, Tyr p, Tyr p 1) and positively associated with atopic dermatitis (Der p 1/2/23, Der f 1/2), asthma (Aca s, Der p 21), food allergy (Aca s, Der f 1, Der p 1), and rural home (Der p 7).

Der p source allergen could reliably rule out relevant IgE levels to HDM components. Strong correlations between HDM allergens and high prevalence of minor and storage mite allergens highlight the challenge of determining which allergens are clinically relevant. Co-sensitization between mite allergens suggests shared epitopes, parallel exposure or sensitization ways. These findings support the need for component-resolved diagnostics to improve prediction of immunotherapy responses.