A 23-year follow-up report of juvenile-onset Sandhoff disease presenting with a motor neuron disease phenotype and a novel variant.

Background: The clinical severity of Sandhoff disease is known to vary widely. Furthermore, long-term follow-up report is very limited in the literature.

Case Presentation: We present a long-term follow-up report of a patient with juvenile-onset Sandhoff disease with a motor neuron disease phenotype. The patient had compound heterozygous variants of HEXB (p.Trp460Arg, p. Arg533His); the Trp460Arg was a novel variant. Long-term follow-up revealed no intellectual deterioration, swallowing dysfunction, or respiratory muscle dysfunction despite progressive weakness of the extremities and sensory disturbances.

Conclusion: We need to be aware of Sandhoff disease in patients with juvenile-onset motor neuron disease.