Acute Renal Failure

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This topic provides information about sudden kidney failure. If you are looking for information about long-term kidney disease, see the topic Chronic Kidney Disease.

What is acute renal failure?

Acute renal failure means that your kidneys have suddenly stopped working. Your kidneys remove waste products and help balance water and salt and other minerals (electrolytes) in your blood. When your kidneys stop working, waste products, fluids, and electrolytes build up in your body. This can cause problems that can be deadly.

What causes acute renal failure?

Acute renal failure has three main causes:

• A sudden, serious drop in blood flow to the kidneys. Heavy blood loss, an injury, or a bad infection called sepsis can reduce blood flow to the kidneys. Not enough fluid in the body (dehydration) also can harm the kidneys.
• Damage from some medicines, poisons, or infections. Most people do not have any kidney problems from taking medicines. People who have serious, long-term health problems are more likely than other people to have a kidney problem from medicines. The medicines that can sometimes harm the kidneys include:
  • Antibiotics, such as gentamicin and streptomycin.
  • Pain medicines, such as aspirin and ibuprofen.
  • Some blood pressure medicines, such as ACE inhibitors.
  • The dyes used in some X-ray tests.
• A sudden blockage that stops urine from flowing out of the kidneys. Kidney stones, a tumor, an injury, or an enlarged prostate gland can cause a blockage.

You have a greater chance of getting acute renal failure if:

• You are an older adult.
• You have a long-term health problem such as kidney or liver disease, diabetes, high blood pressure, heart failure, or obesity.
• You are already very ill and are in the hospital or intensive care (ICU). Heart surgery or belly surgery or a bone marrow transplant can make you more likely to have kidney failure.

What are the symptoms?

Symptoms of acute renal failure may include:

• Little or no urine when you urinate.
• Swelling, especially in your legs and feet.
• Not feeling like eating.
• Nausea and vomiting.
• Feeling confused, anxious and restless, or sleepy.
• Pain in the back just below the rib cage. This is called flank pain.

Some people may not have any symptoms.

How is acute renal failure diagnosed?

Your doctor will ask about symptoms you may have, what medicines you take, and what tests you have had. Your symptoms can help point to the cause of your kidney problem.

Blood and urine tests can check how well your kidneys are working. A chemistry screen can show if you have normal levels of sodium (salt), potassium, and calcium. You may also have an ultrasound. This imaging test lets your doctor see your kidneys.

If you are already in the hospital, tests done for other problems also may find kidney failure.

How is it treated?

Your doctor or a kidney specialist (nephrologist) will try to treat the problem that is causing your kidneys to fail. At the same time, the doctor will try to:

• Help your kidneys rest. You may have dialysis. This treatment uses a machine to do the work of your kidneys until they recover. It will help you feel better.
• Prevent other problems. You may take antibiotics to prevent or treat infections. You also may take other medicines to get rid of extra fluid and keep your body’s minerals in balance.

You can help yourself heal by taking your medicines as your doctor tells you to. You also may need to follow a special diet to keep your kidneys from working too hard. You may need to limit sodium, potassium, and phosphorus. A dietitian can help you plan meals.

Does acute renal failure cause lasting problems?

About half the time, doctors can fix the problems that cause kidney failure in a few days or weeks. These people’s kidneys will work well enough for them to live normal lives.

But other people may have permanent kidney damage that leads to chronic kidney disease. Older people and those who are very sick from other health problems may not get better. People who die usually do so because of the health problem that caused their kidneys to fail.

Frequently Asked Questions

A number of serious conditions or diseases can cause the kidneys to stop working properly. You may develop acute renal failure if:

• You have lost a lot of blood. This can occur because of a serious injury or major surgery.
• You become severely dehydrated because of vomiting or overuse of diuretics.
• You have a serious heart problem, such as heart failure, heart attack, abnormal heart rhythms (arrhythmia), high blood pressure, endocarditis, heart valve disease, or cardiac tamponade.
• You have a disease that causes kidney or liver damage, such as nephrotic syndrome, cirrhosis, lupus, or another disease that causes inflammation of the blood vessels (vasculitis).
• You have another serious condition, such as severe malnutrition, burns, a severe or crushing injury, or severe infection (sepsis).
• You have used medicines that can affect the kidneys, including antibiotics such as gentamicin and streptomycin, ACE inhibitors for high blood pressure, anti-inflammatory drugs such as aspirin and ibuprofen, or the dyes (contrast agents) used in certain X-ray tests.
• You have a sudden blockage that prevents urine from flowing out of the kidneys. Kidney stones, a tumor, an injury, or an enlarged prostate gland can cause a blockage.

The three main types of acute renal failure are:

• Prerenal acute renal failure, which is caused by a sudden serious drop in blood flow to the kidneys.
• Intrinsic acute renal failure, which is the result of damage to the kidneys.
• Postrenal acute renal failure, which is caused by a sudden blockage that prevents urine from flowing out of the kidneys.

Acute renal failure often does not cause symptoms that you notice. If you are already in the hospital, tests done for other problems may also detect your kidney failure. When symptoms do appear, they may include:

• Swelling, especially of the legs and feet.
• Little or no urine output.
• Thirst and a dry mouth.
• Rapid heart rate.
• Feeling dizzy when you stand up.
• Loss of appetite, nausea, and vomiting.
• Feeling confused, anxious and restless, or sleepy.
• Pain on one side of the back, just below the rib cage and above the waist (flank pain).

The symptoms can help your doctor find out what type of kidney failure is present.

• Severe dehydration, a common cause of prerenal acute renal failure, may cause extreme thirst, lightheadedness or faintness, and a weak, rapid pulse.
• A blockage in the urinary tract, which causes postrenal acute renal failure, may cause pain in the side or lower back, blood in the urine (hematuria), or reduced urine output (oliguria).

Uremic syndrome (uremia) is a serious complication of severe or prolonged acute renal failure. It can cause severe nausea, confusion, seizures, irregular heart rhythm, and fluid in the lungs (pulmonary edema).

Acute renal failure occurs within hours to days when the kidneys lose their ability to remove waste products and excess fluids from the body. The most common cause of this is reduced blood flow to the kidneys, either from dehydration, surgery, a severe infection, or injury. When blood flow to the kidneys decreases, waste products and excess fluids are not adequately removed from the body.

Treatment can usually reverse acute renal failure in a few days or weeks. But in some people it causes permanent kidney damage that leads to chronic kidney disease. A small percentage of them will need to have regular dialysis or a kidney transplant.

If acute renal failure is not treated, complications can develop that affect the entire body. These may include:

• Infection. This is one of the most common complications, because the body's immune system may stop working properly.
• Uremic syndrome (uremia). It can cause severe nausea, confusion, seizures, irregular heart rhythm, and fluid in the lungs (pulmonary edema).
• Increased potassium in the blood (hyperkalemia). This can lead to dangerous heart problems.

About half of people who develop acute renal failure recover, and most of those who recover have enough kidney function to live normal lives. Older adults and people who have other serious medical problems are less likely to regain their health. Those who die usually die from the problem that caused their kidney failure, not from the kidney failure itself.

You are more likely to develop acute renal failure if you have certain conditions or diseases, especially if you are an older adult. Conditions that increase your risk include:

• Existing kidney disease or liver disease such as nephrotic syndrome or cirrhosis.
• Diabetes.
• Heart failure.
• High blood pressure.
• Obesity.

Acute renal failure usually occurs in people who are already seriously ill and are in the hospital or intensive care. People who have heart or abdominal surgery or bone marrow transplant have a higher risk.

Acute renal failure is usually diagnosed during a hospitalization for another cause. About 30% of people diagnosed with acute renal failure are in an intensive care unit (ICU).¹

Call your doctor immediately if you have not urinated at all in the last 24 hours.

Call your doctor to schedule an appointment if you:

• Are having trouble urinating.
• Have blood in your urine.
• Are consistently urinating much less than normal.
• Have signs of chronic kidney disease, such as weight loss, nausea and vomiting, swelling, or feeling very tired.

Watchful Waiting

A wait-and-see approach is not appropriate for acute renal failure. If you have been diagnosed with or could have acute renal failure, you need to be treated. Your doctor will take steps to increase blood flow to your kidneys and support the kidneys until they begin working normally.

Who To See

The following health professionals can diagnose acute renal failure:

• Family medicine physician
• Internist
• Pediatrician
• Kidney specialist (nephrologist)
• Nurse practitioner
• Physician assistant

Depending on how bad your acute renal failure is, you may be treated by a nephrologist or an internist. If you are in an intensive care unit (ICU) when renal failure is diagnosed, you will probably be treated by a nephrologist.

To prepare for your appointment, see the topic Making the Most of Your Appointment

Your doctor will begin to evaluate your acute renal failure with a medical history and physical exam. Your doctor will review your health history and hospital chart (if you are currently in the hospital), check all the medicines you are taking, and ask about any other illnesses you have. A complete evaluation is needed to:

• Find the cause of kidney failure. This is an extremely important part of the diagnosis. Identifying the cause is sometimes difficult and may require many tests.
• Know how to treat your condition. How it will be treated and your chances for recovery usually depend on what is causing your acute renal failure.
• Learn how much kidney function remains.
• Detect and treat any complications that may have developed.

Lab tests

Doctors routinely use blood and urine tests to evaluate acute renal failure. These tests can detect a buildup of waste products in the blood and chemical imbalances in the body and may help diagnose another disease or infection you may have.

Blood and urine tests may include:

• Serum creatinine. An increase in the amount of creatinine in the blood (serum creatinine) is usually the first sign of acute renal failure. Repeated tests of serum creatinine can help monitor the progress of renal failure and can help determine whether treatment has been successful. In cases caused by reduced blood flow (prerenal acute renal failure), serum creatinine levels will rapidly return to normal after blood flow or fluid volume is restored.
• Blood urea nitrogen (BUN). BUN measures the amount of nitrogen in your blood that comes from the waste product urea. If your kidneys are not able to remove urea from the blood normally, your BUN level increases.
• Blood electrolyte tests, such as calcium, phosphate (phosphorus), potassium, and sodium.
• Complete blood count (CBC). A CBC provides important information about the red blood cells, white blood cells, and platelets. It can be used to check for diseases or infections that could be causing renal failure.
• Other blood tests, such as an erythrocyte sedimentation rate (ESR, or sed rate) or antinuclear antibodies (ANA) test. These may be used to screen for infection, autoimmune disease, and other disorders, if your medical history and symptoms suggest that one of these conditions might be present.
• Urinalysis, which examines a sample of your urine. The results can provide information about urine sediment, which is useful for evaluating kidney damage (intrinsic acute renal failure). It also looks for:
  • Urine eosinophils (a type of white blood cell). The presence of eosinophils in the urine may be a sign that an allergic reaction is damaging the kidneys. Often the allergic reaction is caused by a medication.
  • Fractional excretion of sodium (Fe_Na) in the urine. It measures how well the kidneys can process sodium (Na), based on the levels of sodium and creatinine in both the urine and the blood. This test can help distinguish prerenal acute renal failure, where there has been no damage to the kidney itself, from intrinsic acute renal failure, caused by damage to the kidneys.
• 24-hour urine collection. Urine output is measured over a 24-hour period. You may have a small tube (catheter) inserted into your bladder to collect all of the urine you produce. Reduced urine output may or may not occur with acute renal failure, depending on the cause. Careful measurement of urine output over time can also help monitor fluid balance in a person who has renal failure.

Imaging tests

Imaging tests provide pictures of your kidneys. They can help your doctor find out whether kidney failure is acute or chronic and check for a blockage in the urinary tract. The imaging tests most commonly used for these purposes are:

• Abdominal ultrasound.
• Computed tomography (CT) scan.
• Abdominal X-ray or a spiral CT scan, which may be used if a kidney stone is suspected.

If a blockage is believed to be causing acute renal failure (postrenal acute renal failure), you may need more extensive tests to determine the location and cause of the obstruction. These tests may include the imaging tests listed above, as well as:

• Retrograde pyelography. During this test, the doctor inserts a thin, lighted tube (cystoscope) into your urethra. A catheter is then put through the cystoscope and into a ureter. Dye is injected through the catheter and X-rays are taken.
• Magnetic resonance imaging (MRI). For this type of MRI, your abdomen is positioned inside a strong magnetic field. The MRI can detect changes in the structure of the kidneys and urinary tract.
• Kidney scan (renal scintigraphy). A kidney scan may also help evaluate whether blood flow to the kidney is normal or whether a blockage is present.

The goals of treatment for acute renal failure are to:

• Correct or treat the cause of kidney failure.
• Support the kidneys until they have healed and can work properly.
• Prevent or treat any complications caused by acute renal failure.

Treating the cause

Because treatment for acute renal failure (ARF) depends on what caused it, treatment can vary widely. Your doctor may need to:

• Replace lost fluids, such as water, blood, and plasma, and restore blood flow to the kidneys. In cases of prerenal ARF caused by dehydration or blood loss, for example, kidney function may quickly return to normal after fluid and blood levels are corrected.
• Discontinue any medications that may be causing the problem. These may include some antibiotics, common pain medicines (nonsteroidal anti-inflammatory drugs) such as aspirin or ibuprofen, blood pressure medicines, and medicines used to treat cancer (chemotherapy).
• Treat kidney disease that is causing damage to the kidneys (intrinsic ARF) by using plasma exchange, glucocorticoids (such as cortisol), or other medicines, depending on the specific disease.
• Use medicines to stop the immune system from working (immunosuppressants), such as cyclophosphamide, when an autoimmune disorder is causing acute renal failure. These disorders include lupus and other diseases that cause inflammation of the blood vessels (vasculitis).
• Remove or bypass a blockage in the urinary tract (postrenal ARF). Kidney function often rapidly returns to normal after a blockage is removed and urine can flow out of the kidneys. Some blockages, such as kidney stones, can be removed. If the blockage cannot be removed, urine flow may be rerouted around the blockage using a catheter or another method. If the bladder is not emptying properly, placing a catheter in the bladder to empty it can quickly relieve symptoms and allow kidney function to return to normal.

Supporting your kidneys

Supporting your kidneys when you have acute renal failure can be complicated. Most people who develop acute renal failure are already in a hospital being treated for another medical problem and already may be critically ill before acute renal failure develops. Treating the primary medical problem may make acute renal failure worse.

As fluid and waste build up in the blood, acute renal failure can lead to severe, life-threatening complications, such as uremic syndrome (uremia) and infection (sepsis). It is important to control early complications, such as fluid overload, chemical imbalances, and anemia, so that more serious complications are less likely to develop.

Support for your kidneys so they can heal will include close management of:

• Fluid intake. Fluids lost because of dehydration or blood loss must be restored, but fluid intake might also be limited, to avoid fluid buildup.
• Nutrition. A specialized diet with restricted fluid intake may be used to meet nutritional needs without putting too much stress on failing kidneys.
• Medications. Several medications are used to help relieve the fluid buildup that can occur in acute renal failure. Your doctor may adjust the dose of your medicines so that they work well for you. Many doctors use diuretics to improve urine output and remove excess water from the body. But some experts feel that they may not be helpful and may actually be harmful to people who are very ill.² Depending on the cause and severity of your acute renal failure, your doctor may choose another method to get rid of extra fluids.
• Causes of urinary blockage, if a blockage is present. If the blockage cannot be removed, urine flow may be rerouted around the blockage using a catheter or a small, flexible tube called a stent.

You may need dialysis daily or every other day to support the kidneys until they recover. Dialysis uses a machine to filter wastes and remove extra fluid from the blood. Hemodialysis is the most common treatment for acute renal failure. It does not shorten or reverse acute renal failure, but it controls blood pressure and corrects life-threatening fluid and electrolyte imbalances that occur when the kidneys are not working properly. Peritoneal dialysis may also be used.¹

Before you start dialysis, your doctor will need to create a dialysis access. The access is the site where the dialysis needles can be inserted to send the blood to and from the dialysis machine. For example, you might have a small tube (catheter) placed in a vein in your arm, leg, chest, or neck. The type of access will depend on the type of dialysis you have.

Recovery

Kidney function may quickly return to normal if the cause of acute renal failure is diagnosed and corrected. Acute renal failure may be corrected within a few days, or it may last for more than a month. Chances of recovery depend on many factors, including what caused the kidneys to fail, how severe the failure was and how long it lasted, how quickly the problem was found and treated, and what other medical conditions you have. For example, acute renal failure caused by dehydration, blood loss, or a blockage in the urinary system often can be reversed quickly without any permanent kidney damage.

About half of people who develop acute renal failure recover. Of those who recover, many have normal kidney function and do not need further treatment. But a few do not regain kidney function and need long-term dialysis or a kidney transplant.¹

What To Think About

Palliative care

If your condition gets worse, you may want to think about palliative care. Palliative care is a kind of care for people who have illnesses that do not go away and often get worse over time. It is different than care to cure your illness, called curative treatment. Palliative care focuses on improving your quality of life—not just in your body, but also in your mind and spirit. Some people combine palliative care with curative care.

Palliative care may help you manage symptoms or side effects from treatment. It could also help you cope with your feelings about living with a long-term illness, make future plans around your medical care, or help your family better understand your illness and how to support you.

If you are interested in palliative care, talk to your doctor. He or she may be able to manage your care or refer you to a doctor who specializes in this type of care.

For more information, see the topic Palliative Care.

End-of-life issues

Acute renal failure is often progressive. After it has developed, you have a greater risk for developing serious problems with infection and heart disease. If you become dependent on dialysis to treat your kidney failure, you may wish to talk to your family and your doctor about health care and other legal issues that arise near the end of life.

You may find it helpful and comforting to state your health care choices in writing (with an advance directive such as a living will) while you are still able to make and communicate these decisions. Think about your treatment options and which would be best for you. You may wish to choose a health care agent to make and carry out decisions about your care if you become unable to speak for yourself. For more information, see the topics Writing an Advance Directive, Choosing a Health Care Agent, or Care at the End of Life.

A time may come when your goals or the goals of your loved ones may change from treating or curing an illness to maintaining comfort and dignity. Your nephrologist will be able to answer questions about your choices when cure is no longer an option. Hospice services focus on providing care and support to you and your loved ones. Hospice caregivers can help you stay as alert and comfortable as possible in a familiar place with family and friends. For more information, see the topic Hospice Care.

Most cases of acute renal failure occur in people who are already hospitalized for another serious injury or illness. Doctors may be able to prevent kidney failure by identifying patients who are at high risk and avoiding medications and other situations that may cause acute renal failure.

Diseases that increase your chance of developing kidney failure are diabetes, high blood pressure, heart failure, obesity, and long-term kidney disease (chronic renal insufficiency). If you have any of these conditions, take extra precautions when starting new medicines. Commonly used medicines, such as aspirin and ibuprofen (nonsteroidal anti-inflammatory drugs), can make kidney function worse in people who already have impaired kidney function, diabetes, high blood pressure, or heart failure.

If you are in the hospital and have a higher risk for developing acute renal failure because of surgery, another medical condition, or a severe injury, your doctor may take precautions to help you avoid acute renal failure:

• Fluid balances will be carefully monitored.
  • Your intake and output will be measured, and you may be weighed every day.
  • Your blood pressure will be checked frequently. You may be given IV fluids to help maintain normal blood pressure.
• You will have frequent blood tests to make sure your electrolytes are in the proper balance.
• Your diet will be managed to make sure that you receive at least 100 grams of carbohydrates each day. The amount of protein in your diet may be restricted.³
• Your medicines will be carefully checked. Medicines that contain magnesium may be stopped. The dosages of your other medicines may be adjusted.

If you have had acute renal failure (ARF) and your kidneys have not recovered fully, you may need to follow a special diet that keeps your kidneys from having to work too hard. A dietitian will work with you to plan a diet that best fits your needs.

Depending on the extent of your kidney damage, other diseases you may have, and whether you are receiving dialysis, you may need to control your intake of minerals (electrolytes) and fluids. You may also have to limit how much protein you eat. In general, you may need to:

• Limit your salt intake. Eating too much salt (sodium) can cause you to retain water, and it increases your risk of heart failure, pulmonary edema, and high blood pressure. It can be hard to avoid sodium. To reduce the amount of salt in your diet, learn to look for hidden sodium in foods, and choose fewer processed foods.
• Watch your potassium intake. Potassium is found in salt substitutes, potassium supplements, and some fruits and vegetables. Too much potassium in your bloodstream (hyperkalemia) can cause muscle weakness and irregular heart rhythms.
• Watch your phosphorus intake. Phosphorus is found in milk, cheese, meat, chicken, and fish. Too much phosphorus in your blood (hyperphosphatemia) can cause calcium to be pulled from your bones, leading to bone problems.

Being on dialysis creates some very special needs. It is important to eat the right number of calories and nutrients to stay as healthy as you can. A nutritionist or dietitian can help you design an appropriate meal plan.

You may be given medicines to treat the underlying cause of your acute renal failure or to prevent complications. For instance, you may take antibiotics to prevent or treat infections, and you may take other medicines to get rid of extra fluid and prevent electrolyte imbalances, which can be dangerous. Your doctor may adjust the dose of your medicines so that they work well for you.

Diuretic medications, such as Lasix, have traditionally been used to treat acute renal failure because they quickly increase urine output. But many experts now feel that they may not be helpful and may actually be harmful to people who are very ill.⁴ Depending on the cause and severity of your acute renal failure, your doctor may choose another method to get rid of extra fluids.

Your nephrologist may talk to you about kidney transplant for acute renal failure if:

• You have severe kidney failure that cannot be reversed by another treatment method.
• You are considered to be a good candidate for surgery. Usually this means that you are in good health other than your kidney problem.

For more information about the issues involved in transplants, see the topic Organ Transplant.

Dialysis

When acute renal failure develops, you may need dialysis. Dialysis is a mechanical process that performs the work of healthy kidneys by:

• Clearing wastes, such as urea, from the blood.
• Restoring the proper balance of certain electrolytes in the blood.
• Getting rid of extra fluid from the body.

Before you start dialysis, your doctor will need to create a dialysis access. The access is the site where the dialysis needles can be inserted to send the blood to and from the dialysis machine. For example, you might have a small tube (catheter) placed in a vein in your arm, leg, chest, or neck. The type of access will depend on the type of dialysis you have.

Two types of dialysis may be used to treat acute renal failure:

• Hemodialysis uses a mechanical membrane (dialyzer) to directly filter wastes and remove extra fluid from the blood. It is the most common treatment for acute renal failure. Hemodialysis is typically done on a daily basis for the best results, especially when a person is critically ill.^{5, 6}
• Peritoneal dialysis uses the lining of the abdominal cavity and a salt solution (dialysate solution) to remove wastes and extra fluid from the body. Peritoneal dialysis is used much less frequently than hemodialysis for the management of acute renal failure.

In order to measure how well dialysis is working, you will have blood samples drawn before and after dialysis. These will be tested to measure the levels of urea (blood urea nitrogen (BUN)) in your blood. By measuring BUN before and after a dialysis treatment, your doctor can learn how well dialysis has removed wastes from your bloodstream.

After severe acute renal failure develops, dialysis is the only way—other than receiving a kidney transplant—to sustain life.

Treatment for blockages

About 5% of acute renal failure cases are caused by a blockage in the urinary tract that causes waste to build up in the kidneys.¹ This is called postrenal acute renal failure. Treatment may be done to remove or bypass the blockage. If a kidney stone is blocking the urinary tract, your doctor can remove or destroy it. The most commonly used medical procedure for kidney stones is extracorporeal shock wave lithotripsy. This treatment uses sound waves that pass easily through the body but are strong enough to break up a kidney stone.

If your doctor cannot remove the blockage, he or she may reroute the urine flow around the blockage using a catheter or another method. Placing a catheter in the bladder to empty it can quickly relieve symptoms and allow kidney function to return to normal.

Organizations

• Chronic Kidney Disease
• Dehydration
• High Blood Pressure (Hypertension)
• Type 1 Diabetes
• Type 2 Diabetes

Citations

1. Brady HR, Brenner BM (2005). Acute renal failure. In DL Kasper et al., eds., Harrison's Principles of Internal Medicine, 16th ed., pp. 1644–1653. New York: McGraw-Hill.

2. Mehta RL, et al. (2002). Diuretics, mortality, and nonrecovery of renal function in acute renal failure. JAMA, 299(20): 2547–2553.

3. Goldfarb DA, et al. (2002). Etiology, pathogenesis, and management of renal failure. In PC Walsh et al., eds., Campbell's Urology, 8th ed., pp. 272–306. Philadelphia: W.B. Saunders.

4. Kellum J, et al. (2006). Acute renal failure, search date January 2007. Online version of Clinical Evidence (15): 1–3.

5. Phu NH, et al. (2002). Hemofiltration and peritoneal dialysis in infection-associated acute renal failure. New England Journal of Medicine, 347(12): 895–902.

6. Schiffl H, et al. (2002). Daily hemodialysis and the outcome of acute renal failure. New England Journal of Medicine, 346(5): 305–310.

Other Works Consulted

• Brady HR, et al. (2004). Acute renal failure. In BM Brenner, ed., Brenner and Rector's The Kidney, 7th ed., vol. 1, pp. 1215–1292. Philadelphia: Saunders.

• Kellum J, et al. (2006). Acute renal failure, search date January 2007. Online version of Clinical Evidence (15): 1–3.

• Shaver MJ, Shah SV (2005). Acute renal failure. In DC Dale, DD Federman, eds., ACP Medicine, section 10, chap. 6. New York: WebMD.

• Singri N, et al. (2003). Acute renal failure. JAMA, 289(6): 747–751.