H Syndrome Associated With Pure Red Cell Aplasia, Rosai-Dorfman Disease, and Sensorineural Hearing Loss: Phenotypic Variability in Three Children With the Same SLC29A3 Mutation.

H syndrome is a rare autosomal recessive disorder caused by mutations in the SLC29A3 gene. We report three pediatric patients with a homozygous c.1309G>A (p.Gly437Arg) mutation presenting with distinct phenotypic variations. These cases expand the clinical spectrum and emphasize the importance of early genetic diagnosis and family counseling.