Delayed Diagnosis of Dopa-responsive Dystonia in Two Siblings.

Background: Dopa responsive dystonia is characterized by progressive disabling dystonia, diurnal variation and a dramatic response to Levodopa. Case characteristics: Two siblings presented with regression of motor milestones and hypertonia in lower limbs. History of diurnal variation was present in elder sibling. Outcome: Both responded dramatically to Levodopa. The genomic DNA analysis of elder sibling revealed a novel mutation. Message: A trial of Levodopa should be considered in a child with motor regression with diurnal variation, in the presence of extrapyramidal features.