Paroxysmal nonkinesigenic choreoathetosis or dystonia.
Incidence
Some cases are clearly inherited as autosomal dominant but other has been sporadic. Rarely relatives of patients may have painful cramps.This condition is more rare than the paroxysmal kinesigenic choreoathetosis or dystonia.
Clinical Characteristics
This condition is more rare than the paroxysmal kinesigenic choreoathetosis or dystonia. Onset is usually in childhood but can begin as late as adult years. Some cases are clearly inherited as autosomal dominant but other has been sporadic. Unilateral or bilateral involuntary movements of the dystonic or choreoatetotic type are not triggered by movements. They may be triggered by stress, alcohol or coffee. The attack lasts longer than the kinesigenic type, usually a few minutes (10 minutes) to several hours. They may be preceded by sensory aura. Speech may be arrested. Consciousness is preserved. Paroxysmal episodes are much less frequent than the kinesigenic type and can be separated by intervals of a few days or even months. Treatment is generally disappointing. It does not respond to anticonvulsants but may benefit from acetazolamide, benzodiazepines (clonazepam) or L-triptophan.
Precipitants
They may be triggered by stress, alcohol or coffee.
Provocation Tests
They may be triggered by stress, alcohol or coffee.
Diagnostic Procedures
EEG and brain MRI is normal. It is a clinical diagnosis. Keep in mind that if patient has developmental delay and microcephaly, it may be a GLUT1 gene mutation.