O'Brien and his colleagues1 recently reported on a review of the world literature on alkaptonuria, ochronosis, and ochronotic arthropathy. In 1859, Boedeker first used the word "alkapton" to describe a reducing substance in the urine of certain patients which had a strong affinity for alkali and caused the urine to become dark brown on standing. The reducing substance was later identified as homogentisic acid by Wolkow and Bauman in 1891. Virchow introduced the term "ochronosis" in 1866 to indicate a clinical disease seen in many young alkaptonuric patients. It was not until 1902 that Albrecht first realized that the three conditions were all various stages of the same disease entity.
Alkaptonuria is an inborn error of metabolism usually inherited as an autosomal recessive gene. There is a wide geographic and racial distribution, but O'Brien and co-workers1 noted it especially in areas where there is a high incidence of