Biotin-responsive basal ganglia disease (BBGD) is a recessive disorder with childhood onset that presents as a subacute encephalopathy, with confusion, dysarthria, and dysphagia, and that progresses to severe cogwheel rigidity, dystonia, quadriparesis, and eventual death, if left untreated.

BBGD symptoms disappear within a few days with the administration of high doses of biotin (5-10 mg/kg/d). On brain magnetic resonance imaging examination, patients display central bilateral necrosis in the head of the caudate, with complete or partial involvement of the putamen.

Etiology

 missense mutations in gene SLC19A3 coding for a transporter related to the reduced-folate transporter (encoded by SLC19A1) and thiamin transporter (encoded by SLC19A2) (#15871139#)