Hypomyelinating leukodystrophy type 6. Clinical and neuroimaging key features in the detection of a new case
Introduction. Hypomyelinating leukodystrophy-6 is a rare and early onset neurodegenerative disease which entails a clinical pattern of pyramidal-extrapyramidal and cerebellar involvement and it comes with a neuroimaging consisting of hypomielination, cerebellar hypoplasia and specific abnormalities in basal ganglia, particularly the absence or nearly absence of putamen and the possible loss of caudate’s volume. It is due to an alteration in tubulin and it is determined by mutations in heterocygosis in TUBB4A gene, showing complete penetrance.
Case report. An 8-year-old child with history of delayed motor development, tremor, dysathria, ataxia, nystagmus, cognitive deficit and dystonia with pattern of hypomielination, vermis hypoplasia and absence of putamen. These findings, although distinctive, had been underestimated in previous evaluations and their detection determined the analyse and identification of a pathogenic variant in TUBB4A gene.
Conclusions. Progressive deterioration leads the patient to total dependence or death in infancy or youth and there is no specific treatment capable of modifying its natural course.
Key words. Ataxia. Dystonia. Hypomyelinating leukodystrophy type 6. Hypomyelination. TUBB4A.