Acute liver or kidney failure happens in cases of hepatorenal syndrome, which is caused by loss of function in the kidneys due to end-stage liver disease. A damaged liver carries a lot of nitrogen in the waste and reduces blood supply to the kidneys over time. In response, the blood vessels of the kidneys become narrow and hamper the functioning of previously healthy kidneys. This results in acute kidney failure. In most cases of hepatorenal syndrome, the only treatment is a liver transplant.