Histamine symptoms and histamine metabolism in chronic granulocytic leukaemia.

Histamine metabolism was investigated in three patients with chronic granulocytic leukaemia (CGL) during symptoms suspected to be caused by histamine release. Plasma histamine levels were excessively high compared with periods when the patients were symptomless or with CGL patients without such symptoms. The patients seemed to be adapted to high plasma histamine levels as the symptoms were not typically systemic in nature, but rather localized phenomena like oedema and pruritus in the extremities. Also CGL patients without symptoms showed abnormally high plasma histamine concentrations, which were significantly related to the whole blood histamine concentration. The possibility must be considered that part of the plasma histamine increase is artificial due to rupture of the basophils during the blood collection procedure.