A case report: recurrent ischemic stroke in a young male patient with isolated positive antiphospholipid igm antibodies

Background: Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by vascular thrombosis and the persistence of antiphospholipid antibodies (aPL). Although aPL have been associated with ischemic stroke in young adults, the optimal antithrombotic strategy to prevent recurrent ischemic stroke remains debated, particularly regarding the efficacy of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs). Case summary: A 41-year-old male with no prior cardiovascular risk factors presented with sudden-onset expressive dysphasia and left hemiparesis. Comprehensive neuroimaging and cardiac evaluations (including 48-hour Holter ECG showing no arrhythmia, ambulatory blood pressure monitoring, and transesophageal echocardiography with saline contrast) did not identify a cardioembolic source or conventional vascular risk factors. Brain MRI demonstrated acute right occipital infarctions, and CT angiography showed narrowing of the distal M1 segment of the right middle cerebral artery (MCA); thrombus could not be distinguished from other causes of stenosis. He was initially discharged on rivaroxaban and rosuvastatin. He suffered a recurrent ischemic stroke involving the right parieto-occipital region despite good adherence to rivaroxaban. Subsequent autoimmune screening revealed isolated positive antiphospholipid IgM antibodies (23.3 U/mL; positive cut-off >10), which remained elevated at a similar level on repeat testing after 12 weeks, with negative anti-cardiolipin, anti-β2-glycoprotein I, p-ANCA and c-ANCA antibodies; lupus anticoagulant results were not available. Treatment was escalated to a VKA (target INR 2.0–3.0) along with hydroxychloroquine and methylprednisolone. At the 1-year follow-up, no recurrent stroke was recorded with good treatment adherence; however, as this is a single case treated with several drugs concurrently, no conclusion can be drawn about the efficacy of the regimen. Conclusion: Screening for antiphospholipid antibodies should be considered in young stroke patients without conventional cardiovascular risk factors, and the diagnosis of APS should be confirmed with standard laboratory tests, including repeat testing after at least 12 weeks. Secondary antithrombotic prevention should be chosen according to the established etiology; although aPL IgM positivity was persistent at 12 weeks, it was isolated and lupus anticoagulant was unavailable, so the evidence from this single case is insufficient to establish APS as the direct cause of the recurrent stroke.