The rare disease involving deficiency in homogentisic acid oxidase is known as alkaptonuria, sometimes referred to as ochronosis. Alkaptonuria is an inherited disorder that occurs when the body is unable to break down the amino acid called homogentisic acid. As a result, homogentisic acid builds up in the body, causing a variety of medical issues such as joint pain, heart disease, and dark urine.
Alkaptonuria is caused by mutations in the HGD gene, which is responsible for producing an enzyme called homogentisic acid oxidase. This enzyme breaks down homogentisic acid into other molecules that the body can use. When the HGD gene is mutated, it causes a deficiency in homogentisic acid oxidase, which prevents the body from properly breaking down homogentisic acid, leading to a buildup of the acid in the body.
The symptoms of alkaptonuria can vary, but they typically include pain and swelling in the joints, dark urine, and a darkening of the skin and cartilage. Alkaptonuria can also lead to heart disease, kidney stones, and hearing loss. Treatment is typically focused on managing the symptoms and preventing complications, such as using nonsteroidal anti-inflammatory drugs to reduce joint pain and swelling. In some cases, a low-protein diet may be recommended to reduce the amount of homogentisic acid in the body.
Alkaptonuria is a rare disorder, but it is important to be aware of it and its potential complications. Early diagnosis and treatment can help reduce the symptoms and help prevent long-term health problems.