Signs of Alkaptonuria
Alkaptonuria is an inherited disorder caused by a genetic defect that affects the body's ability to break down a certain type of amino acid. It is a rare condition, affecting only one in every 250,000 to one million people. People with alkaptonuria are unable to break down a certain type of amino acid, called homogentisic acid. The body then builds up an excess of this acid, which can damage cells and tissues over time.
The signs and symptoms of alkaptonuria usually appear in adulthood, usually in the third decade of life, although they can occur any time after birth. Common signs and symptoms include:
Darkening Skin: Darkening of the skin, and particularly the skin of the ears, eyes, and armpits is one of the earliest signs of alkaptonuria. This is due to the buildup of homogentisic acid in the skin.
Joint Deformities: Joint pain and stiffness is a common symptom of alkaptonuria, as is joint deformity.
Kidney Stones: The buildup of homogentisic acid in the body can cause the formation of kidney stones, which can cause pain and difficulty with urination.
Urine Discoloration: Urine may turn dark brown or black due to a chemical reaction that occurs when homogentisic acid is broken down.
Heart Problems: As the homogentisic acid builds up, it can cause damage to the heart, which can lead to heart failure.
Vision Loss: As alkaptonuria progresses, it can cause vision loss due to the buildup of homogentisic acid in the eyes.
If you or a loved one is exhibiting any of these symptoms, it is important to speak with a doctor as soon as possible. Alkaptonuria can be diagnosed through genetic testing, and treatments are available to help manage the condition.