Biotinidase Deficiency

Biotinidase deficiency is an autosomal recessive disorder characterized by central nervous system and skin manifestations. Individuals with profound deficiency usually present around 3 months of age, but may present as early as the first week of life and as late as 10 years of age. If untreated, the patient may experience seizures, developmental delay, skin lesions, and irreversible sensorineural deafness. Patients are treated successfully with oral doses of free biotin, a water-soluble form of vitamin B. Biotin is routinely recycled in the body when the enzyme biotinidase liberates biotin from endogenous and dietary proteins. Biotin acts as a coenzyme in gluconeogenesis, fatty acid synthesis, and branched chain amino acid catabolism. Biotinidase deficiency diminishes or prevents biotin recycling and coenzyme function.