An Unusual Case of Thromboangiitis Obliterans With Concurrent Deep Vein Thrombosis and Pulmonary Embolism

Buerger's disease (thromboangiitis obliterans (TAO)) is a rare, smoking-related vasculitis that primarily affects distal extremity vessels but can occasionally involve the venous system. We report a 45-year-old heavy smoker with chronic obstructive pulmonary disease (COPD), Raynaud phenomenon, prior digital autoamputation, and necrotic fingertip lesions who presented with dyspnea, hemoptysis, rib pain, and thigh discomfort. He was tachycardic, tachypneic, and hypoxic, with digital gangrene and synovitis. Laboratory studies showed leukocytosis, elevated inflammatory markers, and positive antinuclear antibody (ANA). Duplex ultrasound revealed extensive bilateral deep vein thrombosis (DVT), and CT angiography confirmed acute pulmonary embolism (PE) with right heart strain. The patient was diagnosed with TAO complicated by systemic thromboembolic disease and treated with anticoagulation alongside strict smoking cessation counseling. This case underscores that although TAO is classically a peripheral arterial disease, venous involvement can predispose patients to DVT and PE, especially in the setting of systemic inflammation. Clinicians should maintain suspicion for PE in TAO patients with unexplained respiratory symptoms and emphasize tobacco cessation as essential for preventing recurrence and progression.