LATE PRESENTATION OF BIOTINIDASE DEFICIENCY WITH ACUTE VISUAL-LOSS AND GAIT DISTURBANCE

An unusual presentation of biotinidase deficiency is described, The di sorder classically presents in infancy or early childhood with intract able seizures, hypotonia, ataxia, hearing loss, dermatitis, and alopec ia, A 5-year-old girl developed acute visual loss associated with opti c atrophy, and disturbance of gait with predominantly lower-limb pyram idal signs. She had no seizures, and skin, hair, hearing; and intellec t were normal. Biotinidase deficiency was confirmed biochemically and she responded well to biotin therapy, A diagnosis of biotinidase defic iency should be considered in children with unexplained bilateral opti c neuropathy, particularly when there is accompanying gait disorder.