Venous thrombosis

Hypovolaemia and a hypercoagulable state predispose to venous thrombosis. The hypercoagulable state is due to loss of clotting factors (e.g. antithrombin) in the urine and an increased hepatic production of fibrinogen. Prolonged bed rest should therefore be avoided.

Once renal vein thrombosis has occurred, prolonged anticoagulation is required. Thromboembolism is exceptionally common in nephrotic syndrome due to membranous glomerulonephritis, and in the absence of any contraindication, long-term prophylactic anticoagulation is indicated.

Risks include prolonged sitting, bedrest or immobilization (such as on long plane or car trips), recent surgery or trauma (especially hip, knee or gynecological surgery), fractures, childbirth within the last 6 months and the use of medications such as estrogen and birth control pills.

Deep venous thrombosis is more commonly seen in adults over age 60 but can occur in any age group.

Doctors use several strategies to diagnose DVT. They may also do additional tests, such as venography, in patients with positive D -dimer test results. While all of these strategies seem to be reasonably accurate and safe, we do not know whether some are better than others.