Familial paroxysmal exercise-induced dyskinesia and benign epilepsy: a clinical and neurophysiological study of an uncommon disorder.

We report a family with 6 members affected by a long-lasting paroxysmal exertion-induced dyskinesia. Fasting and stress were precipitating factors. All the patients of this family had also epileptic seizures mainly of generalised type with a favourable outcome. All patients were submitted to a neurophysiological study which included somatosensory evoked potentials by median nerve stimulation (MN-SEPs), somatosensory evoked potentials by posterior tibial nerve stimulation (PTN-SEPs), brainstem auditory evoked potentials (BAEPs), visual evoked potentials (VEPs), motor evoked potentials (MEPs) by magnetic transcranial cortical stimulation (TCS) and electromyography (EMG). The neurophysiological findings suggest a hyperexcitability at the muscular and brain membrane levels, probably due to an ion channel disorder.

A case of Landau-Kleffner syndrome secondary to inflammatory demyelinating disease.

A 6-year old girl developed acquired aphasia with epilepsy and a paroxysmal EEG (Landau-Kleffner syndrome). Isoelectric CSF focusing showed oligoclonal IgG bands. Small lesions were visualized in periventricular left frontal white matter and right parietal lobe centrum semiovale with magnetic resonance imaging (MRI). After a week of ACTH therapy, the EEG paroxysmal activity disappeared; during the next few months, the language disorder improved. Further MRI examination showed a decrease in size and signal of the left frontal lesions, with localized white matter atrophy, dilatation of the subarachnoidal spaces, and disappearance of the right parietal lesion. The clinical and neuroradiologic features and the laboratory data suggest an acute disseminated encephalomyelitis.

Vasovagal reactions induced by head-up tilt and tests of vagal cardiac function.

The vagal cardiac activity was compared in two groups of patients with a history of syncope. Sixty-one patients (Group A) experienced vasovagal reactions induced by head-up tilt, 61 sex and age-matched patients (Group B) did not. No significant differences in vagal cardiac activity between two groups were found. Group A was further subdivided into two subgroups: A1 (14 patients) with stronger, and A2 (47 patients) with smaller cardioinhibition. Again, vagal cardiac activity was not different between two subgroups. Thus, the baseline vagal cardiac activity ('tone') seemed not to be helpful in predicting the susceptibility to vasovagal orthostatic syncope and in discriminating the patients with stronger cardioinhibition.

Electroencephalographic and electrocardiographic features of vasovagal syncope induced by head-up tilt.

Two hundred and seventy-nine consecutive patients referred for transient loss of consciousness, compatible with syncope, underwent head-up tilt to 70 degrees during polygraphic (EEG, ECG, pneumographic) and blood pressure monitorings. Vasovagal syncopes occurred in 28 patients with the following EEG changes: progressive slowing until the appearance of middle or high amplitude delta waves generalized and synchronous in 9 patients; delta waves suddenly followed by transient flattening of EEG activity in 16 patients. In 2 patients EEG could not be interpreted because of muscle and/or movement artifacts. Fifteen out of 28 patients exhibited a marked cardioinhibition, expressed by long-lasting cardiac pauses; a relationship between duration of EEG flat and duration of asystole was not found.

Head-up tilt for triggering and diagnosing syncope.

Head-up tilt to 70 degrees lasting for 30 min is a further useful test for studying syncope. In 26.69% of 109 consecutive out-patients referred for loss of consciousness, it induced vasodepressor and/or cardioinhibitory reactions. All symptomatic patients had similar EEG changes and blood pressure fall during symptoms: by contrast, ECG features, due to vagal activation, were different. The pathogenetic mechanism of vasovagal or vasodepressor syncope is an abrupt sympathetic cardiovascular inhibition with more or less marked vagal cardiac activation. This cardiovascular pattern is due to a cardiac reflex in orthostatic syncope or, probably, to a central activation in emotional fainting.