Alkaptonuria: Rare Form of Disease Shows Major Symptoms in Adulthood
Alkaptonuria is a rare form of a genetic metabolic disorder characterized by the accumulation of homogentisic acid in the body. This disease is also called black urine disease or black bone disease.
Affected people may have dark urine or urine that turns black when exposed to air. However, this change may not occur for several hours after urination and often goes unnoticed.