Plasma histamine concentrations in atopic eczema

Summary 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‐alopic 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.