Sensitisation to mites and other animal-derived home aeroallergens in children and its concordance as a measure of covariation of sensitisation.

Abstract Background Sensitisation to home aeroallergens (mites, furry animals and cockroaches) is predominant in patients in our and other areas. Covariation of sensitisation (CS) to these allergens could be due to cross-reactivity or parallel sensitisation. Methods Skin prick tests were performed to common and second-line home aeroallergens, shrimp and tropomyosin in 253 paediatric patients seen in our Unit due to chronic respiratory symptoms. CS among the main allergens was analysed by means of Cohen's kappa coefficient of concordance ( κ ). Results House dust mites (HDM) were the main allergens involved in sensitisation, followed by furry animals, pollens, storage mites (SM), moulds and cockroaches. CS was very good between D. pteronyssinus and D. farinae ( κ  = 0.81), and good between Dermatophagoides and Euroglyphus ( κ  = 0.71), and decreased markedly to poor ( κ κ  = 0.21–0.44). CS was good between shrimp and tropomyosin ( κ  = 0.62), but null between shrimp-tropomyosin and HDM ( κ  = 0.01–0.02), and poor to fair between shrimp-tropomyosin and SM or cockroaches ( κ  = 0.06–0.34). CS between cat and dog was moderate ( κ  = 0.50). Conclusions We have shown the usefulness of κ in exploring CS in a population. In our area, with high sensitisation to HDM and other home allergens, CS is limited for most pairs of allergens, pointing to a lower incidence of cross-reactivity than could be expected, especially between HDM and SM or other invertebrates.