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Alkaptonuria (AKU) is a rare genetic disorder. People with this condition cannot fully break down a substance in the body called homogentisic acid. This acid builds up in the body over many years. It can turn tissues a dark color and lead to serious problems, especially in the joints and heart.
read more about alkaptonuria ...Alkaptonuria is caused by a faulty gene. It is an inherited disease, which means it is passed down from parents. A child must inherit one faulty gene from both their mother and their father to get the condition. The faulty gene means the body does not make the enzyme that is needed to break down the homogentisic acid.
The very first sign of alkaptonuria is in a baby's diapers. Their urine may turn a very dark brown or black color after it has been exposed to the air for a few hours. A person's earwax may also be a black or reddish-brown color. These early signs are often the only ones for many years.
The symptoms of the disease usually start to appear when a person is in their 30s or 40s. The acid buildup, which is called ochronosis, starts to cause problems. A person may develop severe, early-onset osteoarthritis (joint pain), especially in the spine, hips, and knees. They may also notice dark, blue-black spots on the whites of their eyes and in the cartilage of their ears.
A doctor may suspect alkaptonuria if a person has the classic symptoms, like dark urine or dark spots on their eyes. The diagnosis is confirmed with a urine test. This test will show a very large amount of homogentisic acid in the urine. A genetic test can also be done to find the faulty gene.
There is no cure for alkaptonuria. Treatment is focused on managing the symptoms and slowing down the disease. This includes pain medicine and physical therapy for the joint pain. Many people will eventually need joint replacement surgery. A doctor may also suggest a special diet, and there is one medicine, nitisinone, that can help lower the acid levels.
Yes. While it is not fatal and does not affect thinking, the joint damage it causes can be severe and lead to a serious loss of mobility. It can also cause heart and kidney problems later in life.
Ochronosis is the name for the blue-black pigment that forms from the acid buildup. This is what causes the dark spots on your eyes and ears and the dark staining of your cartilage, which leads to arthritis.
It is extremely rare. It is believed to affect about 1 in every 250,000 to 500,000 people in most parts of the world.
You should see a doctor if you notice dark spots on the whites of your eyes or the cartilage of your ears. You should also see a doctor if you are a young adult and are having severe joint pain or stiffness, especially in your back. If you notice your baby's urine is often black or dark brown, you should tell your pediatrician.
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