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.