When you have nephrotic syndrome, you lose protein through your urine. Proteins do many jobs in your body, and everyone needs protein to live. Your body uses protein to build bones, muscles, and other tissues, and fight infections.

When you have nephrotic syndrome, your kidneys may let a protein called albumin escape through your kidneys’ filters into your urine. Albumin helps your body get rid of extra fluid. When you do not have enough albumin in your blood, fluid can build up in your body, causing swelling in your legs, feet and ankles. You can also start to have other problems, such as blood clots and infections.

With nephrotic syndrome, your body may not get rid of cholesterol in the right way, allowing it to build up in your blood. When you have too much cholesterol in your blood, it can stick together and form clumps inside your veins and arteries. This makes it harder for your heart to pump your blood, and can cause a heart attack or a stroke.

Other complications that can be caused by nephrotic syndrome include: