Outcome of maple syrup urine disease.

The outcome of 12 children with classical maple syrup urine disease is reviewed. All patients presented in the neonatal period at ages varying from 5 to 21 (median 8) days. The time taken to make the diagnosis ranged from 1 day to longer than 9 months (median 7 days). Each survived his initial illness but 3 died later after apparently mild infections. Three of the 12 patients had a spastic quadriplegia and 6 others abnormal neurological signs without clear cerebral palsy. The single most important factor determining the outcome appears to be the time taken to make the diagnosis after the first symptoms. Two patients were diagnosed within 24 hours of the first symptoms and one is of above average ability. The other is mildly retarded but control of the disease was poor in his first 4 years of life. Outcome is unpredictable if the delay is between 3 and 14 days. Two children are of normal ability but 6 others are retarded. A delay longer than 14 days is invariably associated with mental retardation and cerebral palsy. We conclude that early diagnosis is essential to improve the outcome of this condition.