Importancia de la determinación de actividad enzimática en el diagnóstico del déficit de adenosina desaminasa 2 (DADA2)

To describe the usefulness of determining the enzymatic activity of adenosine deaminase 2 (ADA2) in patients with suspected ADA2 deficiency (DADA2).Retrospective multicenter study. Review with analysis of the clinical, biochemical and genetic data of the patients in whom the enzymatic activity of ADA2 has been determined by spectrophotometric method.In 3 of the 20 patients, the diagnosis of DADA2 was confirmed by the combination of reduced enzyme activity and biallelic pathogenic variants in the CECR1 gene. In 2 patients with variants of uncertain significance in CECR1, the study of enzymatic activity allowed to rule out the disease.The reduced enzymatic detection of ADA2 confirms the diagnosis of DADA2, particularly important in carriers of variants of uncertain significance in CECR1.