Beyond the Kidneys: Multisystem Systemic Lupus Erythematosus Presenting With Cardiac Tamponade, Class V Lupus...

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by immune dysregulation, immune complex deposition, and multisystem inflammation with highly variable clinical manifestations. Although lupus nephritis and serositis are common complications, the simultaneous occurrence of biopsy-proven membranous lupus nephritis, cardiac tamponade, polyserositis, dysphagia, and peripheral neurologic manifestations is uncommon and presents significant diagnostic and therapeutic challenges. We present the case of a 37-year-old Hispanic woman with newly diagnosed SLE who developed progressive dysphagia, peripheral sensory deficits, pleural and pericardial involvement complicated by cardiac tamponade, ascites, and biopsy-proven International Society of Nephrology/Renal Pathology Society (ISN/RPS) Class V lupus nephritis. Laboratory evaluation demonstrated a homogeneous antinuclear antibody titer greater than 1:2560, elevated anti-double-stranded DNA antibodies, hypocomplementemia, and approximately 2 g/day of proteinuria. Cross-sectional imaging demonstrated extensive serosal involvement, including bilateral pleural effusions, a large pericardial effusion, pelvic ascites, and perihepatic free fluid. Renal biopsy demonstrated ISN/RPS Class V membranous lupus nephritis with subepithelial, intramembranous, and mesangial immune-type electron-dense deposits and near-global podocyte foot process effacement on electron microscopy. The patient required urgent pericardiocentesis and multidisciplinary management with pulse corticosteroids, hydroxychloroquine, mycophenolate mofetil, and belimumab. Following treatment, her clinical condition improved with resolution of cardiac tamponade and stabilization of her multisystem disease. This case highlights the protean nature of SLE and emphasizes the importance of recognizing simultaneous renal, cardiac, neurologic, gastrointestinal, and serosal involvement. Early multidisciplinary evaluation and prompt immunosuppressive therapy are essential to preventing irreversible organ damage and improving clinical outcomes.