Thalamic hemi-chorea: a rare complication after receiving the adenoviral vector-based COVID-19 vaccine: a case report

Abstract

Lacunar strokes occur when a branch of a large cerebral artery is blocked. The thalamus is often affected, causing uncontrollable motions. A 72-year-old previously healthy man presented with involuntary motions in the right limbs, which were present at rest, and exacerbated during voluntary actions. He had received the first dose of the adenoviral vector-based coronavirus disease 2019 vaccine (ChAdOx1 nCoV-19) 9 days ago. Severe thrombocytopenia and elevated levels of lactate dehydrogenase, ferritin, C-reactive protein, and D-dimer were found, without any evidence of connective tissue disease. Electromyography demonstrated typical choreiform movements, and the brain magnetic resonance imaging indicated a small high signal lesion on the left side of the thalamus. Detection of the immunoglobulin G antibodies against platelet factor 4 in the blood, negative heparin-induced platelet activation (HIPA) test, and positive modified HIPA test confirmed the thalamic stroke due to the vaccine-induced prothrombotic immune thrombocytopenia (VIPIT). He was admitted to the intensive care unit and received nadroparin, sodium ozagrel, edaravone, methylprednisolone, and haloperidol. His hemi-chorea improved gradually over 2 weeks, and he was discharged after 21 days with rehabilitation advice. VIPIT due to the ChAdOx1 nCoV-19 is a novel immune-mediated response that needs clinicians’ awareness and further investigations.

COVID-19 Vaccine-Related Movement Disorders: A Systematic Review

“…One of the cases reported a vaccine induced thrombocytopenia producing an ischemic infarct in the thalamus. 6 Another case reported presence of voltage-gated potassium channel and glutamic acid decarboxylase serum antibodies possibly explaining an autoimmune mediated movement disorder. 7 The possibility of an autoimmune post vaccine reaction was the proposed pathophysiology for the vaccine related movement disorders.…”

“…Another case reported a vaccine-induced prothrombotic immune thrombocytopenia based on cranial imaging hence was given anticoagulants. 6 The researchers used a standardized tool to assess the methodological quality of the studies (Supplement 1). 5 One case report was determined to be high risk of bias which did not describe any neuroimaging results and other ancillary tests to rule out other differential diagnoses.…”

“…13 In another case, a vaccine-induced prothrombotic thrombocytopenia showed ischemia on cranial MRI strategically located on the thalamus. 6 With the lack of clear identifiable laboratory evidence pointing to a different etiology and the universal response to immunotherapy, an autoimmune cause was the proposed pathomechanism in the identified case reports. An abnormal immunological attack resulting to a neuronal dysfunction and manifesting as movement disorder could be one of the most plausible cause of vaccine-induced movement disorder similar to that of adult-onset autoimmune chorea and hemichorea.…”