Biotinidase deficiency in childhood.

This study reports the clinical, laboratory profile and outcome in seven patients with biotinidase deficiency. The serum biotinidase activity was assayed using spectrophotometric analysis. The age at presentation varied from day 1 of life to the 5 th month. Seizures were the presenting complaint in six patients and clonic seizures were the predominant seizure type. Sparse hair was seen in four patients, while three did not have any cutaneous manifestation. None of the patients had acidosis or hyperammonemia. The clinical response to biotin was dramatic with seizure control in all patients. One patient had neurological deficit at follow-up, while none had optic atrophy or sensorineural hearing loss. Biotinidase deficiency, a potentially treatable condition, should be thought of in any child presenting with neurological symptoms, especially seizures, even in the absence of cutaneous or laboratory manifestations.