Some factors influencing the serum IgE levels in atopic diseases.

Diagnosis of atopic diseases can sometimes present difficulties. IgE estimation in serum can obviously be of value in these cases. However, on evaluating the results consideration must be taken of several different factors which may be of importance with regard to the levels of this immunoglobulin. Some of these are discussed here. Patients with asthma and atopic eczema have raised IgE levels more often than patients with hay fever. In the latter cases a significant increase in the IgE level is found during the pollination season. Dust and mould seem to be weak allergens which seldom give rise to elevated IgE levels. Specific hyposensitizaion significantly increased the IgE levels during the first 3 weeks of treatment. Steroids, cytostatics and disodium cromoglycate do not seem to influence the IgE concentrations nor do bacterial or viral infections. Markedly increased IgE concentrations were found in patients with parasitic infestations; Ascaris lumbricoides is one of the parasites of current interest.