Isolated generalized myoclonus immune-mediated by SARS-CoV-2: an illustrative videotaped case.

Myoclonus in the context of COVID-19 is an increasingly recognized condition. The occurrence in an ICU context in hypoxic patients, with metabolic disorders, taking several types of medication, makes difficult to establish a precise cause. Also, the implication of SARS-CoV-2 by direct invasion of the CNS or by immune-mediated phenomena is not yet clear. Currently, a dozen of cases of myoclonus as a predominant clinical manifestation, immune-mediated by SARS-Cov-2 are published. In all these cases, myoclonus was preceded by respiratory or other suggestive symptoms (e.g., anosmia) for this infection making straightforward the causal link. We describe a case of an isolated generalized myoclonus without other clinical complaints nor chest CT scan abnormalities nor SARS-CoV-2 RNA detection on nasopharyngeal swabs and on the CSF, as a para-infectious phenomenon of COVID-19 infection with excellent response to steroids perfusion. This challenging diagnosis was made upon confirmation of seroconversion (serology was negative at admission, then positive for IgM at day 6, then for both IgM and IgG at day 10) underlying that repeating serology is a diagnostic key to capture a similar findings.

Chorea paralytica: a videotape case with rapid recovery and good long-term outcome.

Chorea paralytica (or chorea mollis) is a very rare variant of Sydenham's chorea, characterized by a profound hypotonia, resulting in severe disability. Given the rarity of this condition, data on its prognosis are lacking. Most reports suggest that the delay from onset to recover total autonomy is long, usually several weeks to months which strongly affects the quality of life of these children. We report a videotape case of a 14-year-old girl, who became rapidly bedridden because of severe generalized chorea paralytica. Her clinical picture was totally improved 7 days only after initiation of an "aggressive" treatment, combining steroid pulse, haloperidol and long-term penicillin G, with no relapse after 4-year follow-up. We believe that the best care of this rare and severe form of Sydenham's chorea, should combine pathophysiological treatment with corticosteroids, preferably by pulse-therapy, symptomatic antichoreic treatment by neuroleptics, associated with a long-term antibiotic use to reduce recurrence risk.

Benign myoclonic epilepsy of infancy evolving to Jeavons syndrome.

Benign myoclonic epilepsy of infancy is a rare idiopathic generalized epileptic syndrome occurring below the age of 3 years. Although benign outcome is presumed, some recent studies suggest less favorable outcome. A 14-year-old boy had a history of repeated episodes of myoclonic jerks of the shoulders and upper limbs in infancy (age 5 months). An ictal electroencephalogram indicated generalized spike-wave discharges associated with the myoclonic seizures, and the diagnosis of benign myoclonic epilepsy of infancy was made. Valproate treatment resulted in control of the myoclonic seizures, and the drug was withdrawn when the patient was 5 years of age. At the age of 10, he presented with episodes of eyelid jerks associated with brief lapses in concentration triggered by sunlight. Electroencephalography revealed photosensitivity and a pattern of eye-closure sensitivity. These features were compatible with the diagnosis of eyelid myoclonia with absences, or Jeavons syndrome. Lamotrigine eliminated the seizures. The evolution of benign myoclonic epilepsy of infancy to eyelid myoclonia with absences has been reported in one other case. A possible continuum of myoclonic epileptic syndromes, mediated by a common genetic abnormality, suggests the need for longer monitoring of patients with benign myoclonic epilepsy of infancy.