Rapidly Progressive Cardiac Tamponade in Uncontrolled Rheumatoid Arthritis Complicated by Diabetic Ketoacidosis.

Rheumatoid arthritis (RA) can involve extra-articular organs, including the heart, with pericardial effusions being common but rarely progressing to cardiac tamponade. We report a 42-year-old female with uncontrolled RA, markedly elevated anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF), and type 2 diabetes mellitus, who presented with severe chest pain, shortness of breath, and diabetic ketoacidosis. Rapid accumulation of a large pericardial effusion led to cardiac tamponade, requiring emergency pericardial drainage during a peri-arrest state. Despite aggressive critical care, she developed hypoxic brain injury and multi-organ dysfunction, ultimately leading to death. This case highlights the importance of early recognition of cardiac involvement in RA, the potential severity of extra-articular manifestations even in the absence of active joint disease, and the need for prompt intervention in life-threatening complications.