Kidney Failure (Renal Failure)
by Diane SavitskyEn Espaol (Spanish Version)More InDepth Information on This Condition DefinitionKidney failure occurs when one or both kidneys are not able to perform their usual functions. The kidneys are two bean-shaped organs in the lower back. Their main function is to remove waste from the body and to balance the water and electrolyte content of the blood by filtering the salt and water in the blood. The waste and water excreted by the kidneys combine to form urine. Kidney failure is divided into acute and chronic. Acute kidney failure sudden loss of kidney function Chronic kidney failure slow, gradual loss of kidney function If kidney function is reduced to 20% of normal function, serious health problems develop. When kidney function decreases to 10%-15% of normal, dialysis or a transplant is needed to maintain life. CausesKidney diseases cause the tiny filters in the kidneys (called nephrons) to lose their filtering ability. Damage to the nephrons may occur suddenly after an injury or poisoning. However, many kidney diseases take years or even decades to cause damage that is noticeable. The two most commons causes of kidney failure are:
- Diabetes Longstanding high blood sugar that results from diabetes damages the nephrons.
- High blood pressure Longstanding, severe high blood pressure damages the capillaries in the kidneys
Others causes of kidney failure may include:
- Polycystic kidney disease
- Birth defects
- Bilateral renal artery stenosis
- Severe trauma
- Viral infections: hepatitis B , hepatitis C , HIV/AIDS
- Long-term use of medicines that contain:
- Abnormal build-up of substances within the kidneys, such as:
- Protein build-up
- Toxic reaction to drugs or x-ray dyes
- Systemic diseases, including:
- Conditions that severely decrease circulating fluid/blood volume, such as:
- Conditions that causes obstruction of the flow of urine, such as:
- Enlarged Prostate
- Large kidney stones
- Abdominal tumors blocking the ureters
A blockage from kidney stones has caused renal failure.
2008 Nucleus Medical Art, Inc. Risk FactorsA risk factor is something that increases your chance of getting a disease or condition. Risk factors for kidney failure include: Diabetes Genetics: polycystic kidney disease, type 1 diabetesRace: African AmericansHigh blood pressureLupus or other inflammatory/auto-immune diseases Long-term use of painkillers containing aspirin or NSAIDs in high doses Liver failure, jaundiceRespiratory failureHIVCancerRecent open heart surgery Recent surgery on an abdominal aortic aneurysmCondition that obstructs urine flowEnlargement of the prostate gland Symptoms Some kidney diseases begin without any symptoms at all. As kidney failure progresses, some of the following symptoms may develop: Fluid retentionSwollen hands and feetNumbness of hands and feetItchy skinFatigueLow urine outputFrequent urinationInsomniaAltered consciousnessLoss of appetite, malnutritionSores, bad taste in the mouthNauseaVomitingMuscle cramps and twitchesShortness of breathPericarditisSwelling throughout the bodyHigh blood pressureLow temperatureSeizuresComaBreath smelling like urine (uremic fetor)Yellowish-brownish skin tone DiagnosisThe doctor will ask about your symptoms and medical history, and perform a physical exam.
Tests may include: Blood TestsBlood tests are done to see if the kidneys are working properly. If they are not working properly, blood levels of potassium, phosphorus, parathyroid hormone, and creatinine, as well as blood urea nitrogen will increase. Serum calcium level will decrease. Urine TestsThese tests are also done to see if the kidneys are working properly. If they are not working properly, urine may contain elevated amounts of protein. You may be asked to collect urine in a special container over a 24-hour period. In addition to finding out if you are losing protein in your urine, your doctor can determine how your kidneys are functioning by measuring if your kidneys are clearing creatinine at a normal rate. In severe kidney failure, the amount of urine produced may be quite low and can even be completely absent. Renal imaging This involves use of ultrasound to take a picture of the kidneys. These pictures will show whether there is a blockage in the flow of urine or a growth on the kidney. Biopsy A biopsy involves removing a tiny piece of kidney tissue to see how kidney cells are functioning. TreatmentMost chronic kidney diseases are not reversible, but the following are treatments that may be recommended to help preserve as much kidney function as possible. These treatments will also be use to try to reverse some of the ill effects of kidney failure.
In the cases of acute renal failure treatment is targeted to the illness or injury causing the problem and try to reverse it. General MeasuresFluid restrictionDaily weight checksHigh-carbohydrate dietLow-protein diet MedicationsUse of all medications, both prescribed and over-the-counter, should be carefully reviewed. Medications that rely on the kidney for excretion need to be carefully dosed and monitored, or avoided entirely. Medications used in acute or chronic kidney failure may include: Diuretics, such as furosemide or mannitolto flush out the kidneys, increase urine flow, and rid the body of excess sodiumDopamine, atrial natriuretic peptide (ANP)to dilate blood vessels in the kidneys, increase urine flow, flush out sodiumAngiotensin-converting enzyme inhibitorsBlood pressure medicationsSodium polystyrene sulfonate or insulin in dextroseto control high potassium levelsCalcium acetateto control high phosphorus levels DialysisDialysis is a process that takes over for the kidneys and filters potentially toxic waste from the blood. Dialysis may be done temporarily, until kidney function improves, or until a kidney transplant is available. Kidney TransplantFor some people, receiving a kidney transplant may be the right option. Success of a kidney transplant depends on multiple factors, including whether the underlying cause of the kidney damage is still present, and general state of health of the person receiving the transplant.
Electrolytes, Anemia, and Low Platelet Counts The following blood measures should be monitored: SodiumPotassiumCalciumPhosphateRed blood cellsHematocritPlatelets Injections of erythropoietin, a hormone normally produced by the kidney to stimulate production of red blood cells, may be given to manage the anemia of kidney disease. Lifestyle Changes The following are steps to help your kidneys stay healthy longer: Have your blood pressure checked regularly and use appropriate medication to control high blood pressure.If you are diabetic, control your blood sugar carefully. Ask your doctor or dietitian for help.Avoid the chronic use of pain medications.If you have chronic kidney disease, you may need to limit your intake of protein. A dietitian can help you adjust your diet.Limit cholesterol intake. Cholesterol is present in foods that come from animals, such as meat and dairy products, including eggs.Limit sodium intake.If you have severe kidney disease, limit your potassium intake (found in fruits, vegetables, nuts, and seeds). Help from a dietitian is crucial if your kidneys are failing. Prevention In some cases, you cannot prevent kidney failure. But there are some steps you can take that will lower your risk of kidney failure:
Maintain normal blood pressure.If you are diabetic, control your blood sugar.Avoid long-term exposure to toxic substances such as lead and solvents. Do not abuse alcohol or over-the-counter pain medication. Limit the amount of drugs toxic to the kidney.If you have chronic kidney failure, consult your doctor before you become pregnant. RESOURCES: American Foundation for Urologic Diseasehttp://www.afud.org National Kidney Foundationhttp://www.kidney.org National Kidney and Neurologic Disease Information Clearinghousehttp://kidney.niddk.nih.gov/index.htm CANADIAN RESOURCES: Canadian Diabetes Associationhttp://www.diabetes.ca/ The Kidney Foundation of Canadahttp://www.kidney.ab.ca References: Glomerular filtration rate, proteinuria, and other markers. Am Fam Physician. 2004;70:1091-1097. Johnson CA, Levey AS, Coresh J, et al. Clinical practice guidelines for chronic kidney disease in adults: part I. Definition, disease stages, evaluation, treatment, and risk factors. Am Fam Physician. 2004;70:869-876. Kidney Disease Outcomes Quality Initiative. K/DOQI clinical practice guidelines for bone metabolism and disease in chronic kidney disease. Am J Kidney Dis. 2003;42:S1-201.
Kidney Disease Outcomes Quality Initiative.K/DOQI clinical practice guidelines on hypertension and antihypertensive agents in chronic kidney disease. Am J Kidney Dis. 2004;43:S1-S9. Kidney Disease Outcomes Quality Initiative. Kidney disease outcomes quality initiative (K/DOQI) clinical practice guidelines for chronic kidney disease: evaluation, classification, and stratification. Am J Kidney Dis. 2002;39:S1-266. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: http://www2.niddk.nih.gov/ . Snivel CS, Gutierrez C. Chronic kidney disease: prevention and treatment of common complications. Am Fam Physician. 2004; 70:1921-1928. Last reviewed February 2008 by Miguel Antelo, MDPlease be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.