The excretion of tryptophan metabolites in patients with different forms of haemoblastosis.

The urinary excretion of kynurenine, 3-hydroxykynurenine, kynurenic and xanthurenic acid has been determined by bidimensional paper chromatography in 61 patients with different forms of haemoblastosis (27 cases of Hodgkin's disease, 10 cases of non Hodgkin's lymphomas, 8 cases of acute leukaemia, 11 cases of myeloproliferative disorders, 5 cases of lympho-immunoproliferative disorders). An abnormal urinary excretion of some metabolites of tryptophan's kynurenine pathway is frequent but not constant in all the neoplasias of the myelolymphopoietic system studied so far. In Hodgkin's disease the correlative test between urinary excretion of tryptophan metabolites and clinical stage, histological type and treatment enabled us to point out that the anatomo-clinical diffusion of the lymphoma interferes only through kynurenine and 3-hydroxykynurenine excretion. The histological type seems to influence the 3-hydroxykynurenine excretion. On the contrary, the metabolic alterations present are not affected by treatment. We believe that the metabolic alteration of tryptophan is secondary to a deficit of pyridoxal phosphate and nicotinamide-dependent enzyme activities.