Dancing with disorder: chorea - an unusual and neglected manifestation of antiphospholipid syndrome

Chorea, characterised by involuntary, irregular movements, is a rare neurological manifestation of antiphospholipid syndrome (APS). The specific clinical features remain unclear. This study aimed to summarise the available evidence on antiphospholipid antibody (aPL)-associated chorea.

We used a mixed-methods approach, combining data from patients with chorea with aPL positivity admitted to Peking Union Medical College Hospital (PUMCH) from 2014 to 2024, with cases identified in public databases since 1983. We collected and analysed clinical, laboratory, and imaging results, along with their treatments and outcomes.

A total of 180 patients with incident aPL-associated chorea were included (13 from PUMCH and 167 from the literature). The majority (81.7%) were female, with a mean age of chorea onset 22.8 years (SD=16.0). Chorea was the initial symptom in 87.9% of cases and often occurred as a single episode (67%), involving bilateral limbs (58.8%) and both upper and lower limbs (87.2%). 43.3% met the 2023 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) APS classification criteria. Thrombocytopenia (30.0%) and arterial thrombosis (29.1%) were the most common manifestations. Lupus anticoagulant was positive in 84.2% of patients, anticardiolipin IgG in 70.8%, and anti-β2 glycoprotein I IgG in 52.9%. Among those who had results available for the three tests, 57.6% were triple-positive. ANAs were positive in 63.6%. MRI revealed basal ganglia lesions in only 14.8% of patients, whereas all positron emission tomography (PET) scans showed contralateral striatal hypermetabolism. Treatment varied, with most receiving combination therapies of neuroleptics, anticoagulants, antiplatelets, steroids and immunosuppressants. Chorea completely or partially improved in 95.5% of patients.

Chorea is a significant but under-recognised manifestation of APS, predominantly affecting young women and often presenting as the initial symptom. Characteristic PET findings of contralateral striatal hypermetabolism can assist in diagnosis. Treatments with glucocorticoids and immunosuppressive therapies appear beneficial. Further research is needed to understand the pathophysiology and optimise management strategies for aPL-associated chorea.