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Don’t fight Adenosine deaminase deficiency alone.
Find your community on the free RareGuru App.Adenosine deaminase deficiency (ADA deficiency) is an inherited condition that damages the immune system and is a common cause of severe combined immunodeficiency (SCID). People with SCID due to ADA deficiency are unable to fight off most types of infections, including bacterial, viral and fungal infections. Most people with ADA deficiency develop symptoms before 6 months of age. The earliest symptoms of ADA deficiency include pneumonia, chronic diarrhea, widespread skin rashes, slowed growth, and/or developmental delay. Some people with ADA deficiency will develop symptoms later in life. The symptoms in the late-onset form are typically milder than in the form that occurs in infancy. ADA deficiency is caused by mutations in the ADA gene and is inherited in an autosomal recessive manner. Diagnosis may be suspected by newborn screening or symptoms and confirmed by blood and genetic test results. Currently, the most effective treatment is transplantation of blood-forming stem cells from the bone marrow of a healthy brother or sister of the person with ADA deficiency.
Source: GARD Last updated on 05-01-20
The symptoms of adenosine deaminase deficiency (ADA deficiency) usually begin before 6 months of age. Babies with ADA deficiency usually develop serious lung infections and chronic diarrhea. They have trouble gaining weight and do not grow very well. Other symptoms include skin rashes, absent tonsils and lymph nodes, bone abnormalities, and developmental delay. Approximately 10-15% of people with ADA deficiency do not develop symptoms until later in childhood, often between ages 1 and 10, or even into adulthood. In these cases, people are usually diagnosed with "combined immunodeficiency (CID)", since symptoms are initially milder than those seen in SCID. However, over time, people with the milder form of ADA deficiency may develop chronic lung damage, malnutrition, and other health problems.
There are some people who have partial ADA deficiency. People with this condition have low amount of ADA enzyme in some cells, but have normal immune systems. Partial ADA deficiency is considered a benign condition that does not cause health problems.
Last updated on 05-01-20
Adenosine deaminase deficiency (ADA deficiency) is caused by changes (mutations) in the ADA gene. This gene is responsible for making an enzyme that is found in specialized white blood cells (lymphocytes). Lymphocytes are an important part of the immune system and help protect the body from infections. The function of the ADA enzyme is to convert a substance that is harmful to lymphocytes (called deoxyadenosine) to a non-harmful substance. Mutations in the ADA gene lead to a non-working or poorly working ADA enzyme. This causes deoxyadenosine to buildup in the lymphocytes. Because of this build up, lymphocytes are unable to grow and fight infection, leading to severe combined immunodeficiency.
Last updated on 05-01-20
Most states in the United States screen newborns for severe combined immune deficiency (SCID). One common cause of SCID is adenosine deaminase deficiency (ADA deficiency). If a newborn screen result is abnormal for SCID, additional blood tests are necessary to confirm the diagnosis of ADA deficiency (and other less common causes for SCID). These blood tests include testing for levels of immunoglobulins and white blood cells (WBCs) including T cells, B cells and natural killer cells. Immunoglobulins and WBCs are important parts of the body’s immune system. Genetic testing to identify mutations in the ADA gene may be used to confirm the diagnosis.
In children and adults with the mild form of ADA deficiency, the diagnosis is made based on symptoms which include frequent unusual infections, low WBCs in the blood, absent tonsils or lymph nodes, and low levels of the adenosine deaminase enzyme. Genetic testing for mutations in the ADA gene can confirm the diagnosis of the mild form of ADA deficiency.
Last updated on 05-01-20
Adenosine deaminase deficiency (ADA deficiency) is inherited in an autosomal recessive manner. This means that to have symptoms of ADA deficiency a person must have a mutation in both copies of the responsible gene in each cell. The parents of a child with ADA deficiency usually each carry one mutated copy of the gene and are referred to as carriers. Carriers typically do not show signs or symptoms of the condition. When two carriers of an autosomal recessive condition have children, each child has a 25% (1 in 4) chance to have the condition, a 50% (1 in 2) chance to be a carrier like each of the parents, and a 25% chance to not have the condition and not be a carrier.
Last updated on 05-01-20
The long-term outlook (prognosis) for people with adenosine deaminase deficiency (ADA deficiency) varies depending on the severity of the condition, the timing of the diagnosis, and the response to treatment. Newborn screening for SCID has made it possible for more babies to get diagnosed and treated earlier. This may change long-term outcomes.
For babies diagnosed early and treated with a bone marrow transplant/stem cell transplant, the long-term outlook is generally good. At this time, it isn’t clear if these children will still develop developmental or behavioral problems later in life. People with ADA deficiency who have been treated with gene therapy also seem to have a good long-term outlook, although information is still being collected. People with ADA deficiency who are treated with enzyme replacement therapy (ERT) generally do well, but ERT may lose effectiveness over many years.
Without early diagnosis and treatment, babies with ADA deficiency usually do not survive past age 2.
Last updated on 05-01-20
Adenosine deaminase deficiency (ADA deficiency) affects about 1 in 200,000 – 1 in 1,000,000 people worldwide. About 15% of all cases of severe combined immune deficiency are caused by ADA deficiency.
Last updated on 05-01-20
The treatment of severe combined immune deficiency due to adenosine deaminase deficiency (ADA deficiency) may include the following:
• Early diagnosis and treatment of bacterial, viral, and fungal infections
• Preventative medications for certain types of pneumonia
• Intravenous (IV) immunoglobulin to boost the body's natural response to
infections
• Bone marrow or stem cell transplant
• Gene therapy
The primary treatment is transplantation of blood-forming stem cells from the bone marrow of a healthy brother or sister (allogenic bone marrow transplant /stem cell transplant or BMT/SCT). This therapy is effective in approximately 70% or more of people with severe combined immunodeficiency (SCID), including SCID caused by ADA deficiency.
If a BMT/SCT is not an option, enzyme replacement therapy (ERT) may be recommended. ERT is a treatment that replaces the enzyme that is missing or not working properly (adenosine deaminase) with a bovine form of the enzyme that has been genetically modified to work in humans.
Gene therapy is also available through clinical trials, and appears to be successful in treating people with SCID due to ADA deficiency. Gene therapy involves replacing a copy of the non-working ADA gene with a working copy, so that a person can make the ADA enzyme on his or her own. Gene therapy for SCID due to ADA deficiency has been approved in Europe , but is still considered experimental in the US.
Last updated on 05-01-20
Note, these links are external searches against the National Laboratory of Medicine's drug database. You may need to adjust the search if there are no results found.
| Drug Name | Generic Name |
|---|---|
| Revcovi | elapegademase-lvlr |
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