Shuddering attacks in children: an early clinical manifestation of essential tremor.

Six infants and children presenting with shuddering attacks had evidence and a family history of essential tremor. Although this association had not been recognized, the shuddering spells caused considerable concern and led to a wide range of diagnoses. The attacks start in infancy or early childhood, are brief, often associated with some posturing, and may be very frequent. They are benign and tend to become less frequent or to remit during the latter part of the first decade. The recognition of this syndrome should avoid unnecessary investigation and concern. The pathophysiology of shuddering attacks seems to represent an expression of the mechanism of essential tremor in the immature brain. The ultimate nature of these attacks will undoubtedly be clarified when a neurochemical basis for essential tremor is found.