Introduction: Histamine is the major mediator of IgE- and non-IgE-mediated allergic reactions upon allergen or hapten contact. Reduced histamine degradation capacity was associated with atopic eczema as well as with nonimmunological histamine intolerance. Higher blood serum histamine level concomitant with decreased intestinal diamine oxidase activity were observed in patients with food allergy.

Aim: To evaluate the relationship between patients’ blood diamine oxidase (DAO) activity/histamine status and their reactivity to time-resolved histamine skin prick test in respect to vulnerability to allergic diseases.

Material and methods: Fifty-three patients were examined with skin prick tests (SPT) and patch tests for suspected presence of either IgE- or non-IgE-mediated allergy. All individuals were skin prick tested with histamine and the resolution of the wheal was monitored for 50 min. Blood DAO activity and histamine concentration were measured with a radio-extraction radioimmunoassay