In patients with nephrotic syndrome, the presence of a hypercoagulable state is thought to give rise to a high incidence of thromboembolic phenomena. Renal vein thrombosis is a common complication in nephrotic patients, mainly in those with membranous nephropathy, and many other types of thromboembolic complications also occur. The mortality rate in nephrotic patients with thromboembolic complications may be significantly increased, with pulmonary emboli likely being the most common cause of death.