Ataxia-telangiectasia (A-T) is an inherited disorder that affects the nervous system, immune system, and other body systems. Individuals with this disorder typically have a deficiency in the immunoglobulin G (IgG) subtype of antibodies, which are the primary type of antibodies produced by the body to fight infection.
The main symptom of A-T is an ataxia, which is a lack of coordination and balance. This is usually accompanied by telangiectasia, which is the dilation of small blood vessels in the skin, usually around the eyes, face, and neck. Other symptoms of A-T include a weakened immune system, increased risk of cancer, premature aging, and respiratory problems.
The IgG deficiency in individuals with A-T is caused by a mutation in the ATM gene, which is responsible for producing a protein critical to the functioning of the immune system. This mutation leads to a decreased production of IgG antibodies, which can result in recurrent bacterial and viral infections. Additionally, the lack of IgG antibodies can also lead to a greater risk of developing certain types of cancer, such as lymphoma and leukemia.
Treatment for A-T typically involves immunoglobulin replacement therapy, which provides patients with an artificial form of IgG to make up for the deficiency. Other treatments may include physical therapy to improve coordination and balance, speech therapy to help with speech and language delays, and medications to help manage symptoms, such as respiratory infections. Additionally, individuals with A-T may need to take extra steps to protect themselves from infections, including avoiding contact with people who are ill and getting vaccinated.