House dust mite and storage mite IgE reactivity in allergic patients from Guangzhou, China.

BACKGROUND: In China, house dust mites are important inducers of allergic disease. The importance of allergens from storage mites is less well known.

OBJECTIVE: The aim of this study is to access the prevalence of house dust mite and storage mite sensitization and investigate the IgE crossreactivity between house dust mite and storage mite.

METHOD: The skin prick test (SPT) and specific IgE against the mite species D. pteronyssinus, D. farinae, B. tropicalis, Lepidoglyphus destructor, Glycyphagus domesticus, Tyrophagus putrescentiae and Acarus siro were measured. Included were 412 patients with asthma and/or rhinitis for SPT, 244 for specific IgE and 29 sera for IgE inhibition studies.

RESULTS: The positive SPT prevalence for D. pteronyssinus was 80.3% and for D. farinae 83.7%. The specific IgE prevalence for D. pteronyssinus was 61.1% and for D. farinae 60.2%. The storage mite species, B. tropicalis and T. putrescentiae had the highest positive SPT prevalence, 66% and 63%, respectively. The specific IgE prevalence was highest for B. tropicalis and G. domesticus, 41% and 37%, respectively. Both SPT and specific IgE levels were much higher for house dust mites compared to storage mites. Inhibition measurements showed that none of the storage mites could fully inhibit the specific IgE against D. pteronyssinus. Only in half of the sera could D. pteronyssinus fully inhibit the IgE against L. destructor and G. domesticus while inhibition of the other storage mites were much lower. Nearly all the specific IgE against storage mites could be inhibited by the other storage mites, though B. tropicalis showed a slightly different pattern from the other storage mites.

CONCLUSION: IgE reactivity against storage mites in Chinese patients is due to both storage mite specific IgE and due to IgE mediated crossreactivity to D. pteronyssinus.