A Rare Case of Superior Vena Cava Syndrome in a Patient With Rheumatoid Arthritis and IgA Nephropathy.

Superior vena cava syndrome (SVCS) is a vascular condition resulting from an impaired venous return to the right atrium. The majority of SVCS cases are caused by mass effect in which extrinsic compression of the vessel leads to obstruction of blood flow. In less common cases of SVCS, thrombus formation and luminal narrowing can result in poor return through the SVC. Inflammatory causes of SVCS are even rarer and poorly documented. IgA nephropathy and rheumatoid arthritis (RA) are two autoimmune diseases with the potential to cause vasculitis, thus increasing the likelihood of intraluminal vessel occlusion. We report a rare case of SVCS in a 65-year-old female with a past medical history significant for atrial fibrillation, IgA nephropathy, chronic kidney disease stage IIIA, and RA who presented with headache, dizziness, and neck pain and swelling extending down the left upper extremity for three days. Inflammatory SVCS is uncommon and cases of SVCS secondary to RA and IgA nephropathy are underreported in the literature thus far. Our hope in presenting this case is to encourage a greater degree of suspicion for vascular complications, such as SVCS, in patients with autoimmune and inflammatory conditions.