Kidney failure

Kidney failure
Other names	Renal failure, end-stage renal disease (ESRD), stage 5 chronic kidney disease[1]
A hemodialysis machine which is used to replace the function of the kidneys
Specialty	Nephrology
Symptoms	Leg swelling, feeling tired, loss of appetite, confusion[2]
Complications	Acute: Uremia, high blood potassium, volume overload[3] Chronic: Heart disease, high blood pressure, anemia[4][5]
Types	Acute kidney failure, chronic kidney failure[6]
Causes	Acute: Low blood pressure blockage of the urinary tract certain medications muscle breakdown hemolytic uremic syndrome [6] Chronic: Diabetes high blood pressure nephrotic syndrome polycystic kidney disease [6]
Diagnostic method	Acute: Decreased urine production increased serum creatinine[3] Chronic: Glomerular filtration rate (GFR < 15[1]
Treatment	Acute: Depends on the cause[7] Chronic: Hemodialysis, peritoneal dialysis, kidney transplant[2]
Frequency	Acute: 3 per 1,000 per year[8] Chronic: 1 per 1,000 (US)[1]

Kidney failure, also known as end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels.^[2] Kidney failure is classified as either acute kidney failure, which develops rapidly and may resolve; and chronic kidney failure, which develops slowly and can often be irreversible.^[6] Symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion.^[2] Complications of acute and chronic failure include uremia, hyperkalemia, and volume overload.^[3] Complications of chronic failure also include heart disease, high blood pressure, and anaemia.^[4][5]

Causes of acute kidney failure include low blood pressure, blockage of the urinary tract, certain medications, muscle breakdown, and hemolytic uremic syndrome.^[6] Causes of chronic kidney failure include diabetes, high blood pressure, nephrotic syndrome, and polycystic kidney disease.^[6] Diagnosis of acute failure is often based on a combination of factors such as decreased urine production or increased serum creatinine.^[3] Diagnosis of chronic failure is based on a glomerular filtration rate (GFR) of less than 15 or the need for renal replacement therapy.^[1] It is also equivalent to stage 5 chronic kidney disease.^[1]

Treatment of acute failure depends on the underlying cause.^[7] Treatment of chronic failure may include hemodialysis, peritoneal dialysis, or a kidney transplant.^[2] Hemodialysis uses a machine to filter the blood outside the body.^[2] In peritoneal dialysis specific fluid is placed into the abdominal cavity and then drained, with this process being repeated multiple times per day.^[2] Kidney transplantation involves surgically placing a kidney from someone else and then taking immunosuppressant medication to prevent rejection.^[2] Other recommended measures from chronic disease include staying active and specific dietary changes.^[2] Depression is also common among patients with kidney failure, and is associated with poor outcomes including higher risk of kidney function decline, hospitalization, and death. A recent PCORI-funded study of patients with kidney failure receiving outpatient hemodialysis found similar effectiveness between nonpharmacological and pharmacological treatments for depression.^[9]

In the United States, acute failure affects about 3 per 1,000 people a year.^[8] Chronic failure affects about 1 in 1,000 people with 3 per 10,000 people newly developing the condition each year.^[1][10] Acute failure is often reversible while chronic failure often is not.^[6] With appropriate treatment many with chronic disease can continue working.^[2]