Immunoglobulin E in erythema nodosum.

Twenty-two children aged from 3 years 6 months to 12 years with erythema nodosum (EN) were grouped according to aetiology into streptococcal, tuberculous, and those whose aetiology was undetermined. Serum IgE levels were determined in all by the radioimmunosorbent technique. Levels were higher (mean value 991 units/ml) in streptococcal EN than in those of the other two groups (mean value 68 units/ml and 97 units/ml, respectively) and healthy age-matched controls (mean value 60 units/ml). Increase of IgE levels in individual cases of streptococcal EN did not correlate with severity of the clinical manifestations characteristic of that group.