A case of biotinidase deficiency with unchanged basal ganglia lesions in MRI during an eight year follow-up

Biotinidase deficiency is an autosomal recessive disorder that is presented with dermatitis and neurologic manifestations such as seizure, ataxia, hypotonia, mental retardation and autistic behavior. Basal ganglia lesions in magnetic resonance imaging (MRI) in biotin deficiency was reported and we report a ten year old girl with biotinidase deficiency and basal ganglia lesions in MRI. She is a 10-year-old girl with attacks of seizure from the age of two years. In the first admission, she had mild metabolic acidosis and her brain MRI showed multiple lesions in the basal ganglia and enzyme assay revealed partial biotinidase enzyme deficiency. Treatment with 10 mg daily biotin was started and rapid and good control over seizures was seen. She had episodes of seizure at the ages of four, six and nine years with fever and upper respiratory infection for which biotin dosage was increased. Now and in the last follow up, she is a student of fourth grade of primary school and academic performance is partially favorable and has some residual neurological dysfunction on examination such as dysarthria, ataxia ,and tremor, dystonia of the left hand and mild stiffness of lower extremities. The new brain MRI showed severe degeneration of the caudate nucleus and the putamen that unchanged during the eight year follow-up.