Dihydrolipoyl dehydrogenase deficiency: a therapeutic trial with branched-chain amino acid restriction.

A patient with a deficiency of dihydrolipoyl dehydrogenase and neurological disease is described. The patient was placed on a branched-chain amino acid-restricted regimen. After the introduction of the regimen, there were some biochemical improvements and he achieved some developmental milestones, in contrast to previously reported patients whose neurological disease was progressive. Restriction of the branched-chain amino acids is worth trying among therapeutic measures for this disease, although restriction of the amino acids alone may not totally prevent progression of neurological disease.