Labrune Syndrome: A Rare Leukodystrophy

Abstract

Labrune syndrome is a rare neurological disorder, with less than 100 reported cases since its identification. This disorder causes progressive cerebral degeneration. This case report describes a 21-year-old male patient who presented with tonic-clonic seizures. Upon examination, he was found to have symmetrical dense calcifications in the bilateral basal ganglia, thalami, and dentate nuclei, as well as in the white matter of both hemispheres, accompanied by cysts. MRI brain revealed confluent areas of T2/FLAIR hyperintensities involving the deep periventricular white matter in both cerebral hemispheres with sparing of subcortical U-fibres and two cysts in the left frontal and right posterior temporal region. No serologic evidence of a parasitic infection was found. Treatment was directed at addressing symptoms, and surgery was not required as the cysts were not causing a mass effect. The condition is the result of an autosomal mutation in the SNORD118 gene, a non-protein encoding gene that mediates rRNA synthesis.

Keywords: cerebral calcifications; cysts; labrune syndrome; leukodystrophy; snord118 gene mutation.

Figure 1. Axial sections of CT brain showing multiple calcific foci in bilateral dentate nuclei (a), basal ganglia (b), and bilateral cerebral white matter (c and d). Also, note the white matter cysts and diffuse white matter hypodensity.

Figure 2. MRI of the brain done at the presentation: axial T2-weighted images (a and b) and coronal T2-FLAIR image (c) show confluent periventricular and deep white matter hyperintensity in both cerebral hemispheres suggestive of leukoencephalopathy (solid arrows) with cystic lesions (arrowheads) and T2 dark foci (hollow arrows). Gradient recalled echo images (d, e, and f) show near symmetric foci of blooming in bilateral dentate nuclei (d), bilateral basal ganglia (e), the white matter of both cerebral hemispheres and along the cyst walls (f).

FLAIR: Fluid-attenuated inversion recovery.