Adenosine deaminase deficiency

Severe combined immunodeficiency (SCID) due to adenosine deaminase (ADA) deficiency is a form of the SCID disease group. Due to a mutation in the genome, there is a deficiency of this enzyme, which is responsible for the conversion of adenosine to inosine.

There is an accumulation of toxic purine metabolites, which are the abhorrence of, especially lymphocytes. This mutation is inherited as an autosomal recessive trait and can affect both genders.

The disease is characterized by severe and recurrent opportunistic infections (respiratory infections and candidiasis), caused by profound lymphopenia and very low levels of immunoglobulin. ADA deficiency accounts for 10-15% of SCID cases.

The most common form begins in infancy, however, there are rarer forms which begin later in the 6-24 month of life. Even less often does the disease occur in adulthood.

At the onset of the disease, the immunodeficiency steadily increases. As a rule, the disease leads to death early.