What is the key symptom of deep vein thrombosis (DVT)?

The key symptom of deep vein thrombosis (DVT) is unilateral leg swelling and pain. DVT occurs when a blood clot forms in one of the deep veins, typically in the legs. The clot can cause inflammation, leading to swelling in the affected leg. Patients often report pain in the calf or thigh, which may worsen with activity or prolonged sitting.

The unilateral aspect is particularly important; DVT typically affects only one leg, distinguishing it from other conditions that may cause bilateral symptoms. Recognizing these symptoms is crucial for early diagnosis and treatment to prevent complications, such as pulmonary embolism, where the clot travels to the lungs. Understanding how DVT manifests with these specific symptoms helps healthcare providers identify, manage, and mitigate risks associated with this condition effectively.