Kidney nontumor
Other hereditary renal disease

Topic Completed: 6 February 2012

Minor changes: 12 February 2020

Copyright: 2002-2020,, Inc.

PubMed Search: Ochronosis [title] kidney

Nikhil Sangle, M.D.
Page views in 2019: 821
Page views in 2020 to date: 251
Cite this page: Sangle N. Ochronosis. website. Accessed May 28th, 2020.
Definition / general
  • Autosomal recessive disorder of increased urinary excretion of homogentisic acid (alkaptonuria), with deposition of "ochre colored" (yellow) pigment in collagen rich regions
  • Occurs in 50% with alkaptonuria
  • Due to disorder of homogentisic acid oxidase gene on chromosome 3q, an intermediate component in metabolism of tyrosine and phenylalanine, causing accumulation of benzoquinone acetic acid, which binds to collagen irreversibly
  • Clinically black pigmentation of joints (arthritis with pigment deposition in cartilage and intervertebral disks), cardiovascular system (valvular calcifications and stenosis), kidney (black urine, pigmented stones) and skin (cutaneous pigmentation); also involvement of sclera of eye
  • No effective treatment
Case reports
  • Preventive treatment with avoidance of topical phenols and diets low in tyrosine
Microscopic (histologic) images

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Alkaptonuria ochronosis

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