[Importance of animal epithelia as house dust allergens].

Abstract

Among sera from 379 patients with atopy tested with the radio-allergo-sorbent test (RAST) for domestic dust and house-dust mite (Dermatophagoides pteronyssinus), 104 were positive only for house dust. Positive results for both house dust and house-dust mites were obtained in 130, while in 145 the RAST result was positive only for house-dust mites. 104 sera, negative for house-dust mites, were tested by RAST for specific IgE against epithelia from cats, dogs, guinea-pigs, horses and cattle, as well as cockroaches (Blatella germanica). A positive RAST result for at least one of these animal epithelia was obtained in 89.5% of sera, for cockroaches in 7.7%. Cat epithelia were of special importance with respect to both rate and degree of sensitization. Except for dog epithelia, sensitization (as demonstrated with RAST) against the other domestic animal epithelia was more frequent than the history had indicated. After immune-adsorption of its homologous specific IgE with cat epithelia, but not after adsorption with epithelia of dog, guinea-pig, horse and cattle, inhibition of the house-dust RAST level in 60-80% was demonstrated in pool-sera. This finding proves that sensitization to cat epithelia, in addition to house-dust mites, can be the cause of a positive house-dust RAST reaction; cat epithelia are an important allergen of inhalation allergies caused by house dust.