Individuals on ERT also require periodic monitoring of PEG-ADA levels in plasma and metabolite levels in erythrocytes, and under some circumstances testing for anti-ADA antibodies.Īgents/circumstances to avoid: The use of adenine arabinoside (a substrate for ADA) as an antiviral agent or for chemotherapy of malignancies should be avoided pentostatin, a potent ADA inhibitor used to treat some lymphoid malignancies, would be ineffective in persons who lack ADA, and would interfere with PEG-ADA.Įvaluation of relatives at risk: In the newborn sibs of a proband, it is appropriate to either assay ADA catalytic activity or perform molecular genetic testing (if the family-specific pathogenic variants are known), so that morbidity and mortality can be reduced by early diagnosis and treatment.ĪDA-Deficient Severe Combined Immunodeficiency Disease (SCID) Surveillance: Annual or more frequent evaluation of lymphocyte counts, serum immunoglobulin levels, and various in vitro tests of cellular and humoral immune function following BMT/SCT and during ERT (more frequent monitoring and other specialized testing would be required for participants in gene therapy trials). Gene therapy, which is currently experimental

The longer the disorder goes unrecognized, the more immune function deteriorates and the more likely are chronic sequelae of recurrent infection. Infections in delayed- and late-onset types (commonly, recurrent otitis, sinusitis, and upper respiratory) may initially be less severe than those in individuals with ADA-deficient SCID however, by the time of diagnosis these individuals often have chronic pulmonary insufficiency and may have autoimmune phenomena (cytopenias, anti-thyroid antibodies), allergies, and elevated serum concentration of IgE. If immune function is not restored, children with ADA-deficient SCID rarely survive beyond age one to two years. Infants with typical early-onset ADA-deficient SCID have failure to thrive and opportunistic infections associated with marked depletion of T, B, and NK lymphocytes, and an absence of both humoral and cellular immune function.

Benign 'partial ADA deficiency' (very low or absent ADA activity in erythrocytes but greater ADA activity in nucleated cells), which is compatible with normal immune function.

What gene is mutated in scid