Generalized myoclonus in COVID-19

Area of Science:

• Neurology
• Infectious Diseases
• Immunology

Background:

• Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, causing coronavirus disease 2019 (COVID-19), has been associated with a wide range of neurological manifestations.
• Generalized myoclonus is an uncommon neurological symptom, and its association with COVID-19 requires further investigation.

Observation:

• Three patients (2 male, 1 female; aged 63-88 years) presented with generalized myoclonus and hypersomnia during the inflammatory phase of COVID-19.
• Myoclonus involved facial, trapezius, sternocleidomastoid, and upper extremity muscles, characterized by positive and negative jerks, sensitive to stimuli and voluntary movement, with exaggerated startle.
• Anosmia preceded the onset of myoclonus in all cases. Other causes of myoclonus were excluded, and patients did not experience respiratory arrest or prolonged hypoxia.

Findings:

• The reported cases suggest that generalized myoclonus in the context of COVID-19 may represent a post- or para-infectious immune-mediated neurological disorder.
• The study ruled out other common causes of myoclonus and significant hypoxia, strengthening the link to COVID-19.
• Partial improvement was observed in all three patients following immunotherapy, supporting an immune-mediated etiology.

Implications:

• These findings highlight a potential, albeit rare, neurological complication of COVID-19, expanding the understanding of its clinical spectrum.
• The cases suggest that SARS-CoV-2 might trigger immune responses leading to neurological dysfunction, even without direct viral invasion of the central nervous system.
• Further research is warranted to elucidate the precise mechanisms underlying COVID-19-associated myoclonus and to establish optimal treatment strategies.