Urinary excretion of formiminoglutamic acid in children with riboflavin deficiency.

An increased excretion of urinary formiminoglutamic acid (FIGLU) following an oral dose of histidine has been reported in various conditions other than folic acid deficiency,1 viz., vitamin B12 deficiency,2 hepatic cirrhosis,3,4 malabsorption syndrome,4 megaloblastic anemia associated with pregnancy and malnutrition,5 hemolytic anemia,6 iron-deficiency anemia,5 neoplastic disease,6 thyrotoxicosis,7 congestive cardiac failure,7 skin disorders,7 rheumatoid arthritis's toxemia of pregnancy,9 myelofibrosis,9 infants with protein malnutrition,10 a specific defect in gastrointestinal absorption of folic acid,11 folic acid reductase deficiency,'2 formiminotransferase deficiency syndrome,13 and acute leukemia treated with amethopterin.14 In the present study urinary excretion of FIGLU following an oral histidine load was estimated on children who were deficient in folic acid and/or riboflavin, and the relationship among urinary FIGLU, serum folate and blood riboflavin levels was investigated. The results obtained revealed that there was a tendency to reduction of urinary FIGLU in children with riboflavin deficiency than in those without it.