The anti-Hu syndrome: a clinical and immunological study of 7 cases.

The authors describe the clinical and biological data of seven patients with anti-Hu antibodies. Six of them displayed a small cell lung carcinoma (SCLC), but no cancer was detected in the 7th patient in spite of an extensive workup. The clinical heterogeneity of the anti-Hu syndrome is emphasized. The major symptoms were linked to a severe sensory neuropathy in three cases, to cerebellitis in two cases, to dysautonomia in one case, and to gastro-intestinal pseudo-obstruction in one case. One patient also displayed EMG abnormalities characteristic of the Lambert-Eaton myasthenic syndrome. Two patients developed opsoclonus or ocular flutter associated with severe confusion in the late stage of their disease. In four patients, the neurological signs and symptoms preceded the discovery of the SCLC, and in two cases the initial detection of anti-Hu antibodies prompted the successful search for this tumor. Immunopathological events injuring the peripheral and central nervous system are briefly discussed.

Somatosensory evoked potentials and jerk-locked EEG back-averaging in myoclonic epilepsy.

Median nerve somatosensory evoked potentials (SEPs) and jerk-locked EEG back-averaging (JLA) were performed in 2 patients with left-hand myoclonus. Both SEPs were characterized by a normal parietal N20 and an enhanced N27-P27 fronto-parietal complex, but the giant central N40 described by most authors was only observed in case 1. Similarily, the aspect of JLA clearly differed in both patients. We hypothetize that both patients exhibited signs of an increased drive of the motor cortex by inputs coming from the sensory cortex. This increased drive could be mediated by the cortico-cortical connexions from areas 1-3 to area 4. In contrast, we suggest that signs of primary hyperexcitability of the motor cortex were only present in case 1, as suggested by the presence of an enhanced N40 in SEPs and the results of JLA studies.