• Mohammad Javed
  • Imranullah Khan
  • Nadeem Afzal


Alkaptonuria, also termed ochronosis is a rare metabolic disorder due to a deficiency of the enzymehomogentisic acid oxidase12.Phenyl AlanineTyrosineP-hydroxyphenyl pyruvic acidHomogentisicMaleylacetoacetic acid`Further CatabolismThe result of HGA oxidase deficiency is an accumulation of homogentisic acid in the body andits deposition preferentially in the cartilages, tendons and other tissues as a blue-black or a brownblack pigment. HGA is also excreted in the urine turning it black if left to stand for a while.


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