Curious neurologic sequelae in galactosemia.

Two siblings with classic transferase deficiency galactosemia that was detected at birth have been treated with lactose restriction since the neonatal period. Both patients developed a unique and progressive neurologic syndrome of mental retardation, tremor, and ataxia. Careful review of the family history and medical records, the absence of metabolic disturbances other than those related to galactosemia, and the aggregate physical findings and neurodiagnostic studies ruled out other neurologic disorders in these siblings. It is therefore proposed that these patients represent a subgroup of transferase-deficient galactosemic patients, who develop characteristic neurologic sequelae with conventional dietary management. The existence of this subgroup should be considered in evaluations of therapeutic responses in cohorts of patients with galactosemia. Further, galactosemia should be included in the differential diagnosis of tremor and ataxia in the setting of mental retardation.