Novel imaging findings in two cases of biotinidase deficiency-a treatable metabolic disorder

Abstract

Biotinidase deficiency is one of the few treatable inborn errors of metabolism. We describe unique MRI features in two patients with biotinidase deficiency. Brain MRI in case one demonstrated symmetrical diffusion restriction in bilateral hippocampi, parahippocampal gyri, central tegmental tracts, and cerebellar white matter besides other structures that have been reported previously. The second patient was noted to have bilateral symmetrical T2 hyperintensities involving the anterior, lateral and posterior columns of the entire spinal cord on MRI. Knowledge of the varied MRI features of biotinidase deficiency will aid the prompt diagnosis and treatment of a potentially disabling illness, especially in countries where newborn screening is not routinely performed.

Severe Distal Motor Involvement in a Non-compliant Adult With Biotinidase Deficiency: The Necessity of Life-Long Biotin Therapy

“…Late-onset manifestations in BD have been described in individuals before newborn screening was available and currently in countries where newborn screening is still not implemented. Several individuals between the age of 22 months and 22 years have been reported with spinal cord involvement as initial manifestations (5,7,11,18,(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33). This complication seems to affect predominantly children or young adults with profound BD, often triggered by intercurrent illness, and manifests as spastic tetra-, or more frequently, paraparesis.…”

Neuroimaging Findings of Organic Acidemias and Aminoacidopathies

“…Cerebral cortex and white matter atrophy with secondary enlargement of the ventricular system and extra-axial CSF spaces is the most common finding (27,28). Diffuse or patchy signal intensity abnormalities of the cerebral white matter (frontoparietal region in particular) and cerebellar white matter in association with restricted diffusion and subcortical cyst formation may be seen (28,29). In some children, a Leigh disease-like neuroimaging pattern with symmetric signal intensity abnormalities in the basal ganglia, medial thalami, dorsal midbrain, pons, and medulla may been seen (30).…”

“…In some children, a Leigh disease-like neuroimaging pattern with symmetric signal intensity abnormalities in the basal ganglia, medial thalami, dorsal midbrain, pons, and medulla may been seen (30). Signal intensity abnormality of the entire spinal cord at T2-weighted MR imaging, representing edema and/or demyelination and mimicking neuromyelitis optica, also may be seen (29)(30)(31). Finally, 1 H MR spectroscopy may reveal a lactate concentration peak and decreased NAA level (28).…”

Owl's Eye Sign in a Reversible Etiology of Spastic Quadriparesis

“…1 Spinal involvement may be diffuse 1 or may have selective tract involvement. 4 Bhat et al have described a child with myelopathy and selective involvement of anterior, lateral, and posterior columns. 4 Honavar et al have described selective involvement of anterior and posterior column on neuropathology.…”

“…4 Bhat et al have described a child with myelopathy and selective involvement of anterior, lateral, and posterior columns. 4 Honavar et al have described selective involvement of anterior and posterior column on neuropathology. 2 The spinal involvement of the index child with selective tract involvement has been radiological described as "Owl's eye appearance", which is typically seen in anterior horn cell myelitis but also described with respect to spinal cord infarction, radiation myelopathy, and fibrocartilaginous emboli.…”