Pulmonary Infarction Due to Direct-acting Oral Anticoagulant Malabsorption

A man in his 50s with a history of sleeve gastrectomy and rivaroxaban use for multiple venous thromboembolic events presented with subacute progressive cough. Axial images of a computerized tomography (CT) scan of the chest showed ground glass and consolidations within the right middle and right lower lobes, and he was treated for presumed community-acquired pneumonia. Given continued symptoms despite 7 days of antibiotics, his CT images were re-reviewed. Wedge shaped airspace disease more recognizable in sagittal views prompted concern for pulmonary infarction, and acquisition of a contrast-enhanced chest CT revealed interval increase of a prior pulmonary embolism and findings of acute on chronic thrombosis. Given the patient was adherent to rivaroxaban and had a negative hypercoagulable work-up, rivaroxaban malabsorption related to the patient's sleeve gastrectomy was invoked as the cause of anticoagulant failure, and the patient was successfully transitioned to warfarin therapy, highlighting malabsorption as a cause of recurrent VTE in patients who have received bariatric surgery and who take direct-acting oral anticoagulants.