Introduction: Biotin-thiamine-responsive basal ganglia disease is a rare treatable autosomal recessive neurometabolic disorder

Case Presentation: A  4-month-old baby presented with irritability, and excessive crying. She is born to consanguineous parents (first cousins from the maternal side) with no family history of inherited disorders. Physical examination showed her to be extremelyirritable, with inconsolable crying and macrocephaly; neurological assessment revealed cerebral hypotonia. Brain magnetic resonance imaging showed multiple areas of abnormal signal intensity, which was high on the fluid-attenuated inversion recovery and T2 images noted in the cerebral gray white matter junction as well as the basal ganglia bilaterally. The presentation with the MRI finding  led to the suspicion of biotin-thiamine-responsive basal ganglia disease. She was treated  oral biotin (5 mg/kg/d) and oral thiamine(20 mg/kg/d). genetic testing confirmed homozygous mutation in SLC19A3 gene (c.116T A>C [p.L39S]) The patient showed marked improvement during follow-up; however, 2 months later she has experienced drug resistant epileptic spasms that stopped with tetracosactide acetate. Curently, she is 8-month-old and  suffering dystonia, yet ceased with oral valproic acid (15 mg/kg/d).

Conclusion: The present case illustrates that patients with biotin-thiamine-responsive basal ganglia disease may suffer from various problems, such as seizure and dystonia, during illness course regardless of the early diagnosis and associated treatment.