Renal vein thrombosis

Renal vein thrombosis is a vascular disease, has in which a blood clot (thrombus ) in the renal vein ( renal vein ) is formed. Symptoms are flank pain and bloody urine ( hematuria ). Triggering causes are usually a cancer or a nephrotic syndrome. The diagnosis is made by computed tomography, Doppler ultrasonography or magnetic resonance imaging. Treatment is with anticoagulants heparin and warfarin.

Triggering causes

Most can be a triggering cause be demonstrated. The most common cause (66 % of cases) are cancers, predominantly renal cell carcinoma followed by nephrotic syndrome (20 % of cases), mostly due to membranous glomerulonephritis. Renal vein thrombosis without apparent cause (idiopathic renal vein thrombosis) are rare. In contrast to the deep leg vein thrombosis, the risk of renal vein thrombosis is not increased in familial burden of venous thromboembolism or injury. After surgery, the risk of renal vein thrombosis is increased only when previous kidney transplant.

The age distribution is bimodal with a small increased incidence in the first two decades of life and a significant increase in the disease beyond the age of 70. The causes in the first month of life sepsis, dehydration, and kidney cyst have been described; Causes in the first two decades of life were nephroblastoma, nephrotic syndrome, protein C deficiency, kidney transplantation, sepsis and dehydration.

In 43% of cases, the left renal vein is affected in 33% of the right renal vein and in 21 % both renal veins. In 43 % of cases, the thrombus extending into the inferior vena cava ( inferior vena cava ).

Clinic

The most common symptoms are flank pain in 73 % of cases and bloody urine ( hematuria ) in 36 % of cases. Non-specific symptoms such as anorexia, nausea and fever are common (> 40 % of cases). In half of the cases is found on physical examination, a tremor of the hands ( asterixis ).

Laboratory

In about half the cases, there are limited kidney function and increased protein excretion in the urine. In 5 percent of cases, there is a requiring dialysis renal failure and in 20 percent of cases of nephrotic syndrome.

In some cases, a protein S deficiency, or antithrombin deficiency have been described in the context of an enlarged coagulation diagnostics.

Diagnosis

Diagnosis is made by imaging methods such as computed tomography, Doppler sonography, magnetic resonance imaging with gadolinium as a contrast agent and arterio - or venography.

Therapy

Treatment is usually with the anticoagulant drugs heparin and warfarin. The treatment is carried out usually at least 6 months, possibly throughout life. Rarely come acetylsalicylic acid, fibrinolysis or Cavaschirm used.

Forecast

Older works report after gone renal vein thrombosis on recurrence rates of 8.5 % to 27 %. In a recent study repeated thromboembolic events were rare (1 in 100 patient-years). These were mostly deep vein thrombosis; the recurrence of renal vein thrombosis was not described.

If the renal vein thrombosis cancer or an infection based on the life expectancy is reduced. In patients with renal vein thrombosis due to the nephrotic syndrome there is no limitation of life expectancy. Therapy with warfarin ( in Germany is instead usually used warfarin ) improves the prognosis.