Alcaptonuria: a rare cause of abnormal coloration of the urine: a case report in the neonate.

Alcaptonuria is a rare hereditary disease, characterized by an abnormal bla ckish coloration of the urine and dark pigmentation of the conjunctive tiss ue which is due to a deficiency in homogentisate 1,2-dioxygenase (HGO), a p henylalanine catabolizing enzyme. An accumulation of homogentisate (HGA) is then formed, and is responsible for the dark coloration which only occurs after the urine has been exposed to air over a period of time. Signs of thi s disorder therefore frequently remain unnoticed during childhood, because the urine requires a relatively long exposure to air before it changes colo r. Diagnosis is generally made at a later date, during adulthood, following complications such as ochronosis, inflammatory arthritis, or urinary calcu li. Case report - in this study the case has been described of alcaptonuria dia gnosed in a five-month old infant No efficient cure has yet been found, alt hough certain treatments, including high doses of vitamin C, do seem to hav e a beneficial effect on limiting the complications associated with this di sorder. Early diagnosis whenever possible is therefore important Conclusion. - This case report is interesting because of the early diagnosi s involved. In the event of any abnormal coloration of the urine, diagnosis may be established via the addition of an alkylating agent, and the levels of HGA determined by chromatography. (C) 2000 Editions scientifiques et me dicales Elsevier SAS.