Biotinidase deficiency is a rare potentially treatable cause of peripheral neuropathy with or without optic neuropathy in adults

摘要

We describe two adult brothers with lower limb neuropathy and one with progressive optic neuropathy. One brother was found to have profound biotinidase deficiency by identifying biallelic pathogenic variants of the BTD gene by whole exome sequencing, which was confirmed by markedly decreased serum biotinidase activity.