Rare Nephrology News

Disease Profile

Exogenous ochronosis

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Ochronosis, acquired


Exogenous ochronosis (EO) refers to the bluish-black discoloration of areas of the skin, especially the face, ear cartilage, the ocular (eye) tissue, and other body locations. It occurs as the result of exposure to malarial drugs, skin lightening creams and over-exposure the the sun.[1] Other than the skin discoloration, there are no other health effects. EO does not typically appear until adulthood and may be difficult to diagnose. There is no specific treatment for this condition. Treatment options exist, and include prescription skin creams, vitamins, laser treatments and other skin treatments. Exogenous ochronosis is different from hereditary ochronosis, which is an inherited condition that occurs with alkaptonuria.[2][1]

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.


  1. Bhattar PA, Zawar VP, Godse KV, Patil SP, Nakarni NJ, Gautam MM. Exogenous Ochronosis. Indian J Derm. Nov-Dec 2015; 60(6):537-43. https://www.ncbi.nlm.nih.gov/pubmed/26677264.
  2. Vashi N. Kundu R. Acquired hyperpigmentation disorders. UpToDate. Sept 28, 2017; https://www.uptodate.com/contents/acquired-hyperpigmentation-disorders.