Kidney failure is a condition that affects more than 200,000 people in the United States. Kidney failure can cause a variety of medical problems, including low blood pressure, swelling of the extremities, and muscle paralysis that can eventually lead to death. Kidney failure can also have a significant impact on other diseases, most notably the cardiovascular diseases. There are two different types of kidney failure: acute and chronic. Acute kidney failure is characterized by a rapid loss of kidney function. Acute kidney failure is typically caused by low blood volume due to the loss of blood from an injury, obstruction of the urinary tract, or the kidney being exposed to a substance that is harmful to its normal function. In most cases, acute kidney failure is treated by providing treatment for the underlying cause of the kidney failure, with dialysis sometimes being used as a bridge to help the kidney function while the patient is being treated. Chronic kidney failure typically develops slowly over time, and is usually the result of disease progression or an irreversible acute disease. Kidney function may be replaced with dialysis, but many sufferers of chronic kidney failure require a kidney transplant at some point in their treatment. There are a variety of different symptoms of kidney failure, and there may be few, if any, symptoms in the early stages of kidney failure. Vomiting, diarrhea, and dizziness are common symptoms of the early stages of kidney failure. As the condition progresses and the kidneys weaken, other more severe symptoms begin to appear. Swelling of the legs, arms, and other extremities begins to appear as the kidneys struggle to remove excess fluid from the body. The final stages of kidney failure bring severe pain in the back and sides, bloody urine, and difficulty breathing due to extra fluid on the lungs. Patients at this stage of the condition need dialysis to replace the kidney function; untreated kidney failure will eventually lead to the death of the patient.