Abnormal platelet aggregation in severe combined immunodeficiency disease with adenosine deaminase deficiency.

The platelets from a boy with adenosine deaminase deficiency-severe combined immunodeficiency disease (ADA-SCID) showed markedly subnormal aggregation in response to collagen and ADP. In contrast with normal platelets, ATP, AMP and adenosine had little effect in inhibiting ADP-induced aggregation of ADA-SCID platelets. These observations suggest that altered adenosine metabolism exists in ADA-SCID platelets.