Metabolic Findings in a Patient with Adenosine Deaminase Deficiency and Severe Combined Immunodeficiency

Abstract

Although more than 30 families with adenosine deaminase (ADA) deficiency and severe combined immunodeficiency (SCID) have been described the precise mechanism through which the deficiency of ADA produces immunodeficiency is still unknown. Only in the past few years the investigations on purine metabolites in some patients with ADA deficiency and SCID^1-4 have enhanced our understanding of the immune dysfunction. Here we describe the metabolic findings observed in a 10 week-old girl with SCID and ADA deficiency. The patient was hospitalized for respiratory distress and mucocutaneous Candidiasis. Severe impairment of both cellular and humoral immunity was found. The ADA activity was measured⁵ in a red cell hemolysate and was found to be absent. The ADA level in the mother’s red cells was 0.07Δ E293 nm/hour/mg hemoglobin (normal x= 0.231±0.080) and in the father’s red cells 0.14. The patient worsened rapidly and died 3 weeks later. Autopsy confirmed the diagnosis of SCID with presence of Candida in the lung, kidney, heart and brain.