Concomitant Large Loculated Pleural and Pericardial Effusions in a Patient with Rheumatoid Arthritis on Methotrexate.

Rheumatoid arthritis (RA) is the most common multisystemic autoimmune inflammatory joint disorder, affecting nearly 1.3 million adults in the US. RA has high economic and social burdens. Functional disability may arise in RA from the characteristic chronic progressive inflammation and the erosion of multiple joints and cartilage damage. Systemic manifestations of RA include rheumatoid nodules, pleuropulmonary complications, pericarditis, rheumatoid vasculitis, Felty's syndrome (the rare triad of rheumatoid arthritis, splenomegaly, and neutropenia), amyloidosis, and neurological complications. We present the diagnostic challenges of differentiating pleuropulmonary and pericardial complications of rheumatoid arthritis from side effects of therapy (rheumatoid pleural and pericardial effusions vs immune suppression associated side effects and infections). We use the Naranjo score to facilitate this decision-making process. A 52-year-old man with a history of RA, chronic small right pleural effusion, and hypertension on long-term oral methotrexate and corticosteroid therapy presented to the emergency room after 1 week of worsening respiratory symptoms. A chest radiograph demonstrated a large pleural effusion and pneumonia. Intravenous methylprednisolone and antibiotics were administered. A video-assisted thoracoscopic procedure was performed, chest tubes were inserted, and abatacept was eventually initiated as adjunctive therapy to methotrexate and corticosteroid therapy for the rheumatoid arthritis and lung condition. Abatacept is an immunosuppressive fusion protein composed of the Fc region of immunoglobulin G1 fused to the extracellular domain of cytotoxic T-lymphocyte-associated protein 4, which interferes with the immune activity of T cells.