Open AccessExcretion of tryptophan metabolites by patients with rheumatoid arthritis
Author(s) -
Flinn John H.,
Price J. M.,
Yess Norma,
Brown R. R.
Publication year - 1964
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.1780070303
Subject(s) - tryptophan , rheumatoid arthritis , excretion , kynurenine , xanthurenic acid , pyridoxine , medicine , endocrinology , tryptophan metabolism , metabolism , pyridoxine deficiency , urinary system , serotonin , chemistry , biochemistry , amino acid , receptor
Abstract The urinary excretion of tryptophan metabolites was measured in control subjects, in patients with active rheumatoid arthritis, and in patients with related disorders. After tryptophan loading, 12/15 female patients and 4/5 male patients with active rheumatoid arthritis and a positive latex test had significantly elevated levels of one or more of the tryptophan metabolites measured. Hydroxykynurenine and kynurenine were the metabolites most frequently elevated. Although excretion of 4‐pyridoxic acid was in the normal range in these subjects, administration of supplements of pyridoxine restored tryptophan metabolism toward normal in a group of 11 female patients in which this was studied. The data suggests that a high percentage of these patients have a functional pyridoxine deficiency demonstrable in tryptophan metabolism only by means of a tryptophan loading test.