Lupus causes chronic renal failure by weakening the kidneys. Kidneys are the key organs of the renal system, and they remove waste from the urine and blood and balance body fluids. Lupus frequently leads to Lupus nephritis, a condition when lupus causes kidney tissue to inflame, leaving the kidneys unable to perform waste removal from the urine or blood or to regulate the fluid volumes of the body. This can result in chronic renal failure.
High blood pressure, or hypertension, can also cause kidneys to fail by causing the blood vessels and arteries leading to the kidneys to degenerate. When the blood vessels are no longer able to deliver enough blood to the kidneys for them to efficiently filter waste or to regulate fluid volume in the body, this also results in chronic renal failure.