• Home

Home > Medical Reference > Encyclopedia (English)

Toggle: English / Spanish

Alkaptonuria

• Overview
• Symptoms
• Treatment
• Prevention

Alternative Names:

AKU; Alcaptonuria; Homogentisic acid oxidase deficiency; Alcaptonuric ochronosis

Symptoms:

Urine in an infant's diaper may darken and can turn almost black after several hours. However, many persons with this condition may not know they have it until mid-adulthood, around age 40, when joint and other problems occur.

Symptoms may include:

• Progressive arthritis, especially of the spine
• Darkening of the ear
• Dark spots on the white of the eye ( sclera ) and cornea

Signs and tests:

A urine test ( urinalysis ) is done to test for alkaptonuria. If ferric chloride is added to the urine, it will turn the urine a black color in patients with this condition.

• Review Date: 7/2/2007
• Reviewed By: Brian Kirmse, M.D., Department of Human Genetics, Mount Sinai School of Medicine, New York, NY. Review provided by VeriMed Healthcare Network.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process . A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.