Antiphospholipid‐related chorea: two case reports and role of metabolic imaging

Crossed-reflex in antiphospholipid chorea

Chorea is a hyperkinetic movement disorder associated with various underlyingconditions, including autoimmune diseases such as antiphospholipid syndrome (APS). APS can manifest with a wide range of neurological symptoms, including chorea. We present a case of a 77-year-old man with subacute generalized chorea secondary to primary APS. Notably, the patient exhibited a left patellar crossed-reflex, a phenomenon rarely documented in chorea cases, the pathophysiology of which has not yet been elucidated. In summary, this case challenges the traditional demographics of antiphospholipid syndrome (APS) by suggesting a potential link between APS and late-age patients. It emphasizes the importance of considering APS in late-onset chorea cases.

Neuropsychiatric Systemic Lupus Erythematosus: Molecules Involved in Its Imunopathogenesis, Clinical Features, and Treatment

Systemic lupus erythematosus (SLE) is an idiopathic chronic autoimmune disease that can affect any organ in the body, including the neurological system. Multiple factors, such as environmental (infections), genetic (many HLA alleles including DR2 and DR3, and genes including C4), and immunological influences on self-antigens, such as nuclear antigens, lead to the formation of multiple autoantibodies that cause deleterious damage to bodily tissues and organs. The production of autoantibodies, such as anti-dsDNA, anti-SS(A), anti-SS(B), anti-Smith, and anti-neuronal DNA are characteristic features of this disease. This autoimmune disease results from a failure of the mechanisms responsible for maintaining self-tolerance in T cells, B cells, or both. Immune complexes, circulating antibodies, cytokines, and autoreactive T lymphocytes are responsible for tissue injury in this autoimmune disease. The diagnosis of SLE is a rheumatological challenge despite the availability of clinical criteria. NPSLE was previously referred to as lupus cerebritis or lupus sclerosis. However, these terms are no longer recommended because there is no definitive pathological cause for the neuropsychiatric manifestations of SLE. Currently, the treatment options are primarily based on symptomatic presentations. These include the use of antipsychotics, antidepressants, and anxiolytic medications for the treatment of psychiatric and mood disorders. Antiepileptic drugs to treat seizures, and immunosuppressants (e.g., corticosteroids, azathioprine, and mycophenolate mofetil), are directed against inflammatory responses along with non-pharmacological interventions.

Antiphospholipid-related chorea

Chorea can be associated with autoimmune diseases such as antiphospholipid syndrome and has been associated with the isolated presence of antiphospholipid antibodies (aPL). Chorea is a rare neurological manifestation of antiphospholipid syndrome. The pathophysiological mechanisms underlying aPL-related chorea are still debated. One postulated mechanism is aPL or other autoantibody binding to brain-blood vessel endothelium, resulting in endothelial dysfunction secondary to a proinflammatory cascade, with sequalae of inflammation and local microthrombosis. Another postulated mechanism considers immune-mediated attack (aPL or antibasal ganglia antibodies) against specific basal ganglia epitopes. Here, we report a patient with isolated aPL-related chorea that followed a relapsing-remitting course. We highlight the role of brain metabolic imaging with fluorodeoxy glucose positron-emission tomography in the diagnostic workup of chorea and the challenges in the practical management of aPL-related chorea with symptomatic treatments.