IgE antibodies to house dust mite in patients with scabies.

Of 135 patients with scabies, forty-seven (35%) had a positive (Classes 1--4) radioallergosorbent test (RAST) to Dermatophagoides pteronyssinus (DP). Elevated serum IgE concentrations were found in sixty-one (45%) of the patients. Atopic disease was confirmed in twenty-eight (23%) of the 120 patients who completed a medical questionnaire satisfactorily. In a control group, well-matched for age and sex, of 201 employees at a local bank, only four (2%) had a positive RAST to DP, and eight (4%) had raised serum IgE levels. Atopic disease was confirmed in eighteen (9%) of them. These observations indicate that scabies infection stimulates the production of IgE antibodies, even in non-atopic individuals, and may suggest that IgE antibodies against the human pathogenic mite Sarcoptes scabiei cross-react with DP. Scabies infection in addition often seems to be associated with atopic disease.