title: Rhythmic cortical myoclonus in a case of HIV-related encephalopathy.
abstract: We describe a 66-year-old, HIV-seropositive patient presenting with ataxia and upper limb rhythmic myoclonus activated by postural maintenance. Electromyograph (EMG) recordings of the forearm muscles showed 50-msec bursts, with a frequency of 10 Hz, concurring with frontocentral electroencephalograph (EEG) rhythmic activity. Autoregressive spectral analysis applied to the EEG-EMG traces made it possible to detect significant coherence between the rhythmic EEG discharges and EMG bursts. The amplitude of the middle-latency somatosensory evoked potentials was increased. Long-latency reflexes were enhanced. On the basis of the electrophysiological findings, the movement disorder should be considered a rhythmic variant of cortical myoclonus. In our patient, HIV infection may have caused a dysfunction in the central nervous system pathways involving the cerebellum and sensorimotor cortex, similar to that occurring in genetically determined conditions characterised by cortical myoclonus.
authors.affiliation: Department of Clinical Neurophysiology; Istituto Nazionale Neurologico Carlo Besta, Milan, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Canafoglia
authors.forename: Ferruccio
authors.initials: F
authors.lastname: Panzica
authors.forename: Silvana
authors.initials: S
authors.lastname: Franceschetti
authors.forename: M Rita
authors.initials: MR
authors.lastname: Carriero
authors.forename: Claudia
authors.initials: C
authors.lastname: Ciano
authors.forename: Vidmer
authors.initials: V
authors.lastname: Scaioli
authors.forename: Luisa
authors.initials: L
authors.lastname: Chiapparini
authors.forename: Elisa
authors.initials: E
authors.lastname: Visani
authors.forename: Giuliano
authors.initials: G
authors.lastname: Avanzini
mesh_terms: D015526:AIDS Dementia Complex / Q000150:complications*; D000368:Aged; D001284:Atrophy / Q000473:pathology; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology*; D004569:Electroencephalography; D004576:Electromyography; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D010507:Periodicity