D-Dimer for Pulmonary Embolism

An 82-year-old woman with bladder cancer and treated hypertension was referred by her family physician after she reported experiencing a few days’ history of mild fever, cough, limited deep inspiration, and left-sided pleuritic chest pain. She had no personal or family history of venous thrombosis and did not have any recent surgery, trauma, or admission to hospital. Her long-term medications included fluoxetine, vitamin D, and hydrochlorothiazide. On examination, temperature was 38.3°C (101°F), blood pressure was 157/78 mm Hg, pulse rate was 82 beats per minute, and respiratory rate was 20 breaths per minute. Oxygen saturation was 97% in room air. She had a regular heart rate with a mild systolic murmur; her jugular venous pressure was normal; and lung auscultation revealed reduced air entry at the left base. She had no leg swelling and no pain on calf palpation. Laboratory testing results are reported in Table 1. The attending physician raised the diagnosis of a pulmonary embolism (PE) among the differentials. The clinical probability of PE was unlikely (Wells score).