Two cases of ADA2 deficiency presenting as childhood polyarteritis nodosa: novel ADA2 variant, atypical CNS manifestations, and literature review.

Deficiency of adenosine deaminase 2 (DADA2) is an autosomal recessive disease resulting from loss-of-function pathogenic variants in ADA2 gene, which might resemble polyarteritis nodosa (PAN). The authors present two pediatric cases of ADA2 deficiency with phenotypic manifestations of PAN, including an unusual presentation with spinal cord ischemia. Also described is an assessment of ADA2 activity and gene expression profiling with description of a previously unreported homozygous variant, c.