A venous thrombosis can form anywhere in the body, and symptoms depend on the site of the clot.
The legs are one of the more common sites. Signs and symptoms include pain or stiffness, swelling and redness in the affected leg. The discomfort may start anywhere from the upper thigh to the ankle. All of these signs and symptoms do not need to be present if you have a blood clot in your leg. Often, patients experience only swelling and some discomfort. If the clot or part of the clot travels to the lungs — a pulmonary embolism — you can experience chest pain, shortness of breath or lightheadedness.
Some patients receive drugs or fluids via catheters placed into veins. Catheters can stimulate thrombus formation in the vein near and around the catheter, called a catheter-associated DVT. Because the catheters are usually located in an arm or in the chest, such a thrombus can lead to arm or neck swelling, with or without pain.
Patients with inflammatory bowel disease and patients with certain blood disorders, including myeloproliferative neoplasms and paroxysmal nocturnal hemoglobinuria, sometimes develop thrombosis in veins in the abdomen. This is called a mesenteric venous thrombosis. Mesenteric venous thrombosis sometimes causes abdominal discomfort, but may have no associated symptoms.
Reviewed by health care specialists at UCSF Medical Center.