D-Dimer must be ordered alongside which of the following tests?

D-Dimer is a blood test that measures the presence of fibrin degradation products, which can indicate the presence of an abnormal blood clot in the body. It is especially useful in the evaluation of conditions such as pulmonary embolism (PE) or deep vein thrombosis (DVT). In clinical practice, when D-Dimer is elevated, it often prompts further diagnostic imaging to confirm or rule out these conditions.

Ordering a CT Angiogram (CTA) of the chest or a Ventilation-Perfusion (VQ) scan after measuring D-Dimer is appropriate because these imaging modalities are designed specifically to visualize potential pulmonary emboli. The CTA provides detailed images of the blood vessels in the lungs, allowing for the identification of clots, while the VQ scan assesses both airflow and blood flow in the lungs, which can also help diagnose PE.

The other options, such as a chest X-ray, urinalysis, and CT abdomen, do not have the same direct relevance to the evaluation of thromboembolic disease as a CTA or VQ scan does when used in conjunction with a D-Dimer test. While a chest X-ray may be used as an initial imaging study for various chest concerns, it does not specifically assess for blood cl