Proteinuria is an excess of protein in the blood. When there has been damage to the kidneys, depending on the cause, you may develop protein in your urine. With Systemic lupus erythematosis (SLE), we generally develop a "glomerulonephritis", or lupus nephritis, which causes proteinuria.
In some people, proteinuria may persist or even worsen over time. It is for this reason that you will need additional tests to assess the extent of your proteinuria in order to determine the best treatment for controlling it.
Because Lupus is a disease that is constantly changing, which means that it usually has chronic histological changes, it follows that glomerulonephritis will also change during the course of the disease. It is for this reason that regular tests are done to assess proteinuria and to determine the function of the kidneys and the severity of glomerulonephritis.
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