renal vein thrombosis

Renal vein thrombosis (plural: renal vein thromboses) can be either from "bland" thrombus or tumor thrombus (extension of tumor into the vein). There are numerous etiologies for bland thrombus, but it most commonly occurs in the hypercoagulable nephrotic syndrome. Renal vein thrombus is commoner on the left side, presumably due to the left renal vein being considerably longer than the right.

Pathology

• in children, renal vein thrombosis is the most common vascular condition in the neonatal kidney
  • dehydration and sepsis are common underlying factors for renal vein thrombosis
  • sickle cell disease 
  • polycythemia
  • maternal diabetes
  • indwelling umbilical venous catheters
• in adults, renal vein thrombosis can result from a variety of disorders, including:
  • nephrotic syndrome
  • systemic lupus erythematosus
  • amyloidosis
  • glomerulonephritis
  • collagen vascular disease
  • diabetes mellitus
  • renal sepsis (thrombophlebitis)
  • tumor thrombus, e.g.
    • renal cell carcinoma
    • lymphoma
    • in rare cases, adrenal carcinoma
  • urinary obstruction (rare) 

• trauma is another potential cause of renal vein thrombosis

Complications include pulmonary embolism, renal atrophy, and papillary necrosis. Bland thrombus can coexist with tumor thrombus.

Radiographic features

Ultrasound

Grayscale ultrasound findings include:

• renal enlargement with hypoechoic cortex from edema (early phase)
• decreasing size and increased echogenicity (late)

Doppler findings include:

• reversal of arterial diastolic flow
• absent venous flow
• visualization of thrombus within the lumen
• high resistance in the renal artery with elevated resistive index

 CT

• as with venous thrombosis elsewhere, the thrombosis is observed as a filling defect during venous phase imaging following intravenous contrast
• enlarged kidney may reach to a very large size
• persistent cortical enhancement and lack of parenchymal enhancement
• changes in attenuation, either focal or diffuse, may be present due to perfusion abnormalities
• collateral vessels may appear around the kidney in chronic cases

MRI

MR renal venography may be performed, especially if the patient has renal impairment which does not permit the use of intravenous contrast medium .

Treatment and prognosis

• treatment of nephrotic syndrome: steroids and immune-suppression therapy
• treatment of underlying renal cell cancer includes surgery for early-stage disease
• anticoagulation therapy

Complications

Recognized complications of renal vein thrombosis include:

• pulmonary embolism
• renal atrophy
• renal papillary necrosis

Siehe auch:

• Lungenarterienembolie
• Diabetes mellitus
• Nierenzellkarzinom
• systemischer Lupus Erythematodes
• Amyloidose
• Nebennierenrindenkarzinom
• Glomerulonephritis
• collagen vascular disease
• Papillennekrose der Niere
• Nierenvenenthrombose bei Kindern
• renal vein thrombosis and adrenal hemorrhage
• Nephrotisches Syndrom
• doppler findings in renal vein thrombosis

und weiter:

• Nussknacker-Syndrom
• striated nephrogram
• renal papillary necrosis (mnemonic)
• papillary necrosis (mnemonic)
• posterior nutcracker phenomenon
• low signal intensity renal parenchyma
• Komplikationen nach Nierentransplantation
• Pyelonephritis mit Nierenvenenthrombose
• Varizen der Vena renalis