Plasma histamine concentrations in atopic eczema.

Plasma histamine concentrations were determined using a radio-enzymatic assay in fifty-four patients suffering from atopic eczema and in thirty-nine controls (contact dermatitis, psoriasis and normal non-atopic healthy volunteers). While in none of the controls histamine levels in plasma exceeded 1 ng/ml, seventeen out of fifty-four patients with atopic eczema showed increased plasma histamine concentrations ranging between 1.2 and 5.2 ng/ml. Elevated plasma histamine levels were found mostly in patients with severe eczema and high serum IgE levels. Longitudinal studies in seven patients revealed normal plasma histamine values during clinical remission.