Spinal hypomyelination in a child with classic hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC): expanding the neuroradiological spectrum, a case report.

BACKGROUND: Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a progressive hypomyelinating leukodystrophy caused by pathogenic variants in the tubulin beta-4A gene (TUBB4A). Some patients exhibit clinical symptoms suggestive of spinal cord involvement; however, spinal cord magnetic resonance imaging (MRI) findings have rarely been described. CASE PRESENTATION: We performed spinal cord MRI in an 11-year-old boy carrying the most common, prototypical H-ABC-associated TUBB4A variant (p.D249N) and identified hypomyelinating changes in the spinal cord. In addition to the typical motor symptoms, he exhibited impaired vibration and joint position sense in the lower limbs, suggestive of posterior column involvement of the spinal cord. On somatosensory evoked potential (SEP) testing, spinal segmental responses were preserved, whereas the more rostral components were absent. DISCUSSION/CONCLUSION: Our case indicates that spinal hypomyelination can also be present in H-ABC. The concordant clinical findings, spinal MRI abnormalities, and SEP results in our patient suggest involvement of the dorsal column pathways and indicate that spinal cord pathology could contribute to the clinical manifestations and disease severity.