Medical Tests & Procedures Archive

Most people don't need to fast before a lipid test because the difference between LDL cholesterol values when fasting or not fasting is very small. But people who have had high triglyceride levels should fast prior to the test.

Leg pain may be caused by deep-vein thrombosis (DVT), a blood clot that forms in a deep vein, usually in the leg. Left untreated, the clot may break off, travel to the lungs, and cause blockage in a lung artery, known as pulmonary embolism (PE), which can be life threatening. Diagnosis of DVT and PE may include a review of symptoms, a D-dimer blood test, a leg ultrasound, or a chest CT scan. Both conditions are most often treated with direct-acting oral anticoagulants.

The approach to certain blood tests appears to be shifting. Doctors might stop ordering routine vitamin D screenings for healthy people younger than 75; they might order a one-time combination of lipoprotein(a), C-reactive protein, and LDL (bad) cholesterol tests as a way to predict future heart problems; and they might rely less on standard ranges designated as "normal" in a complete blood count (CBC) test, and instead focus more on comparing someone's latest CBC results to previous CBC tests.