HYDROXYKYNURENINURIA is a disorder of tryptophan metabolism in respect of its conversion to nicotinic acid in which the individual excretes large amounts of xanthurenic acid, kynurenine, and 3-hydroxykynurenine on a normal diet, without the stress of a tryptophan load.
A girl, now 14 years of age, came to us in 1952 when she was 3 weeks old. Diarrhea and ulceration of the mouth occurred within ten days of birth, the diarrhea progressing to an entero-colitis with blood and mucus. Hemolytic anemia, apparently of the acquired type, occurred at 3 weeks of age; Coombs' test was negative. The general condition of the child deteriorated after a blood transfusion; a marked hepatosplenomegaly and jaundice developed which finally disappeared after several weeks. This was not explained; the blood had been carefully cross-matched. High fever and diarrhea persisted intermittently until 5 months of age.
Dwarf stature was noted soon after birth and the child