Studies on
tryptophan metabolism in PEM were performed. In this respect, the basal excretion of
tryptophan and some of its metabolites, namely,
kynurenine, 3
OH-anthranilic, anthramilic, indol-3-acetic, 5
OH-indol acetic and xanthurenic
acids were determined. The response of these metabolites to oral
tryptophan load, singly and in combination, with
pyridoxine, were performed in
kwashiorkor cases compared to normal controls. The study revealed that
kynurenine leads to niacine pathway is hindered,
Indole-3-acetic acid levels are lower and respond poorly to
tryptophan loading in PEM. Increased levels of 5
OH-indol acetic were found in
kwashiorkor compared to
marasmus, although lower response to
tryptophan was noted.
Xanthurenic acid excretion is much higher in PEM and poorly responds to
tryptophan load either singly or in combination with
pyridoxine. These errors of
tryptophan metabolism in PEM are suggested to be due to defects in the
enzyme systems involved rather than to
vitamin B6 deficiency.