Sneddon syndrome without antiphospholipid antibodies: a possible link to rheumatic fever—a case report

Sneddon Syndrome (SS) is a rare medium-vessel vasculopathy characterized by livedo reticularis and ischemic cerebrovascular events. In some cases, it is associated with antiphospholipid antibodies (aPL), suggesting an autoimmune mechanism. However, SS can occur without aPL, representing an idiopathic variant with poorly understood pathophysiology. This report presents a case of SS without aPL, highlighting diagnostic challenges and potential links to prior inflammatory processes, such as rheumatic fever. A 35-year-old white woman with a history of childhood rheumatic fever presented with progressive livedo reticularis over 11 years, initially without associated symptoms. Five years prior, she developed tonic–clonic seizures and transient right upper limb motor deficits. Imaging revealed cerebral white matter ischemic lesions consistent with microangiopathy. Skin biopsy showed no thrombi, and aPL serology was negative. Management included antiplatelet therapy and adjusted anticonvulsants, leading to partial neurological improvement. This case underscores the diagnostic challenges of SS without aPL, often leading to delayed recognition and delayed ischemic event prevention. The patient’s rheumatic fever history raises an underexplored question: could prior inflammatory processes trigger endothelial dysfunction and microangiopathy in SS? While no direct evidence exists, a potential underlying autoimmune component warrants further investigation. Idiopathic SS treatment lacks consensus, though anticoagulation and anticonvulsants may reduce symptoms. However, no therapies are proven to alter disease outcomes. SS without aPL lacks established guidelines, complicating diagnosis and management. This case emphasizes the need for individualized approaches beyond aPL status. The patient’s rheumatic fever history may hint at an unexplored inflammatory mechanism in SS pathophysiology, meriting future study.