NORMAL VALUES OF URINARY OROTIC-ACID IN A HEALTHY TUNISIAN POPULATION

Background - Orotic acid (OA) is an intermediary metabolite of pyrimid ine synthesis. An elevation of urinary erotic acid excretion has been described in congenital defect of the urea cycle enzymes and in primar y orotic aciduria. Several techniques have been used to measure OA and many reference values are published without considering age and sex. Population and methods. - The reference values of urinary OA excretion , expressed in mu mol/mmol of creatinine, are reported in a healthy Tu nisan population using a calorimetric method. The study included 20 me n and 20 women (age = 31 +/- 11 years) and 30 children aged from 3 day s to 8 years. Results. - There was a significant increase (P < 0.01) o f urinary OA excretion in women (4.38 +/- 1.35) compared to men (3.26 +/- 0.80) and of children (5.03 +/- 1.14) compared to adults (3.82 +/- 1.24). Urinary OA excretion was significantly higher among children a ged less than 1 year compared to alder children. Conclusion. - It is n ecessary for every laboratory practicing this kind of exploration to h ave its own norms which depend on both age and sex. (C) 1998, Elsevier , Paris.