This article needs additional citations for verification .(May 2024) |
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:
Chronic: [6] |
Diagnostic method | Acute:
Chronic:
|
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] In Canada, the lifetime risk of kidney failure or end-stage renal disease (ESRD) was estimated to be 2.66% for men and 1.76% for women. [11] Acute failure is often reversible while chronic failure often is not. [6] With appropriate treatment many with chronic disease can continue working. [2]
Kidney failure can be divided into two categories: acute kidney failure or chronic kidney failure. The type of renal failure is differentiated by the trend in the serum creatinine; other factors that may help differentiate acute kidney failure from chronic kidney failure include anemia and the kidney size on sonography as chronic kidney disease generally leads to anemia and small kidney size.[ citation needed ]
Acute kidney injury (AKI), previously called acute renal failure (ARF), [12] [13] is a rapidly progressive loss of renal function, [14] generally characterized by oliguria (decreased urine production, quantified as less than 400 mL per day in adults, [15] less than 0.5 mL/kg/h in children or less than 1 mL/kg/h in infants); and fluid and electrolyte imbalance. AKI can result from a variety of causes, generally classified as prerenal, intrinsic, and postrenal. Many people diagnosed with paraquat intoxication experience AKI, sometimes requiring hemodialysis.[ citation needed ] The underlying cause must be identified and treated to arrest the progress, and dialysis may be necessary to bridge the time gap required for treating these fundamental causes.[ citation needed ]
Chronic kidney disease (CKD) can also develop slowly and, initially, show few symptoms. [16] CKD can be the long term consequence of irreversible acute disease or part of a disease progression.[ citation needed ] CKD is divided into 5 different stages (1–5) according to the estimated glomerular filtration rate (eGFR). In CKD1 eGFR is normal and in CKD5 eGFR has decreased to less than 15 ml/min. [17]
Acute kidney injuries can be present on top of chronic kidney disease, a condition called acute-on-chronic kidney failure (AoCRF). The acute part of AoCRF may be reversible, and the goal of treatment, as with AKI, is to return the person to baseline kidney function, typically measured by serum creatinine. Like AKI, AoCRF can be difficult to distinguish from chronic kidney disease if the person has not been monitored by a physician and no baseline (i.e., past) blood work is available for comparison.[ citation needed ]
Symptoms can vary from person to person. Someone in early stage kidney disease may not feel sick or notice symptoms as they occur. When the kidneys fail to filter properly, waste accumulates in the blood and the body, a condition called azotemia. Very low levels of azotemia may produce few, if any, symptoms. If the disease progresses, symptoms become noticeable (if the failure is of sufficient degree to cause symptoms). Kidney failure accompanied by noticeable symptoms is termed uraemia. [18]
Symptoms of kidney failure include the following: [18] [19] [20] [21]
Acute kidney injury (previously known as acute renal failure) – or AKI – usually occurs when the blood supply to the kidneys is suddenly interrupted or when the kidneys become overloaded with toxins. Causes of acute kidney injury include accidents, injuries, or complications from surgeries in which the kidneys are deprived of normal blood flow for extended periods of time. Heart-bypass surgery is an example of one such procedure.[ citation needed ]
Drug overdoses, accidental or from chemical overloads of drugs such as antibiotics or chemotherapy, along with bee stings [25] may also cause the onset of acute kidney injury. Unlike chronic kidney disease, however, the kidneys can often recover from acute kidney injury, allowing the person with AKI to resume a normal life. People with acute kidney injury require supportive treatment until their kidneys recover function, and they often remain at increased risk of developing future kidney failure. [26]
Among the accidental causes of renal failure is the crush syndrome, when large amounts of toxins are suddenly released in the blood circulation after a long compressed limb is suddenly relieved from the pressure obstructing the blood flow through its tissues, causing ischemia. The resulting overload can lead to the clogging and the destruction of the kidneys. It is a reperfusion injury that appears after the release of the crushing pressure. The mechanism is believed to be the release into the bloodstream of muscle breakdown products – notably myoglobin, potassium, and phosphorus – that are the products of rhabdomyolysis (the breakdown of skeletal muscle damaged by ischemic conditions). The specific action on the kidneys is not fully understood, but may be due in part to nephrotoxic metabolites of myoglobin.[ citation needed ]
Chronic kidney failure has numerous causes. The most common causes of chronic failure are diabetes mellitus and long-term, uncontrolled hypertension. [27] Polycystic kidney disease is another well-known cause of chronic failure. The majority of people affected with polycystic kidney disease have a family history of the disease. Systemic lupus erythematosus (SLE) is also a known cause of chronic kidney failure. Other genetic illnesses cause kidney failure, as well.[ citation needed ]
Overuse of common drugs such as ibuprofen, and acetaminophen (paracetamol) can also cause chronic kidney failure. [28]
Some infectious disease agents, such as hantavirus, can attack the kidneys, causing kidney failure. [29]
The APOL1 gene has been proposed as a major genetic risk locus for a spectrum of nondiabetic renal failure in individuals of African origin, these include HIV-associated nephropathy (HIVAN), primary nonmonogenic forms of focal segmental glomerulosclerosis, and hypertension affiliated chronic kidney disease not attributed to other etiologies. [30] Two western African variants in APOL1 have been shown to be associated with end stage kidney disease in African Americans and Hispanic Americans. [31] [32]
Chronic kidney failure is measured in five stages, which are calculated using the person's GFR, or glomerular filtration rate. Stage 1 CKD is mildly diminished renal function, with few overt symptoms. Stages 2 and 3 need increasing levels of supportive care from their medical providers to slow and treat their renal dysfunction. People with stage 4 and 5 kidney failure usually require preparation towards active treatment in order to survive. Stage 5 CKD is considered a severe illness and requires some form of renal replacement therapy (dialysis) or kidney transplant whenever feasible.[ citation needed ]
A normal GFR varies according to many factors, including sex, age, body size and ethnic background. Renal professionals consider the glomerular filtration rate (GFR) to be the best overall index of kidney function. [33] The National Kidney Foundation offers an easy to use on-line GFR calculator [34] for anyone who is interested in knowing their glomerular filtration rate. (A serum creatinine level, a simple blood test, is needed to use the calculator.)
Before the advancement of modern medicine, renal failure was often referred to as uremic poisoning. Uremia was the term for the contamination of the blood with urea. It is the presence of an excessive amount of urea in blood. Starting around 1847, this included reduced urine output, which was thought to be caused by the urine mixing with the blood instead of being voided through the urethra.[ citation needed ] The term uremia is now used for the illness accompanying kidney failure. [35]
Two other urinary indices, are the fractional sodium excretion (FENa) index and the renal failure index (RFI). [36] The renal failure index is equal to urine sodium times plasma creatinine divided by urine creatinine. [36] A FENa score greater than 3% or a renal failure index (RFI) greater than 3 are helpful in confirming acute renal failure. [37]
Those with end stage renal failure who undergo haemodialysis have higher risk of spontaneous intra-abdominal bleeding than the general population (21.2%) and non-occlusive mesenteric ischemia (18.1%). Meanwhile, those undergoing peritoneal dialysis have a higher chance of developing peritonitis and gastrointestinal perforation. However, the rate of acute pancreatitis does not differ from the general population. [38]
The treatment of acute kidney injury depends on the cause. [7] The treatment of chronic kidney failure may include renal replacement therapy: hemodialysis, peritoneal dialysis, or kidney transplant. [2]
In non-diabetics and people with type 1 diabetes, a low protein diet is found to have a preventive effect on progression of chronic kidney disease. However, this effect does not apply to people with type 2 diabetes. [39] A whole food, plant-based diet may help some people with kidney disease. [40] A high protein diet from either animal or plant sources appears to have negative effects on kidney function at least in the short term. [41]
People who receive earlier referrals to a nephrology specialist, meaning a longer time before they must start dialysis, have a shorter initial hospitalization and reduced risk of death after the start of dialysis. [42] Other methods of reducing disease progression include minimizing exposure to nephrotoxins such as NSAIDs and intravenous contrast. [43]
Nephrology is a specialty for both adult internal medicine and pediatric medicine that concerns the study of the kidneys, specifically normal kidney function and kidney disease, the preservation of kidney health, and the treatment of kidney disease, from diet and medication to renal replacement therapy. The word "renal" is an adjective meaning "relating to the kidneys", and its roots are French or late Latin. Whereas according to some opinions, "renal" and "nephro" should be replaced with "kidney" in scientific writings such as "kidney medicine" or "kidney replacement therapy", other experts have advocated preserving the use of renal and nephro as appropriate including in "nephrology" and "renal replacement therapy", respectively.
Azotemia is a medical condition characterized by abnormally high levels of nitrogen-containing compounds in the blood. It is largely related to insufficient or dysfunctional filtering of blood by the kidneys. It can lead to uremia and acute kidney injury if not controlled.
Kidney dialysis is the process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally. Along with kidney transplantation, it is a type of renal replacement therapy.
Uremia is the condition of having high levels of urea in the blood. Urea is one of the primary components of urine. It can be defined as an excess in the blood of amino acid and protein metabolism end products, such as urea and creatinine, which would normally be excreted in the urine. Uremic syndrome can be defined as the terminal clinical manifestation of kidney failure. It is the signs, symptoms and results from laboratory tests which result from inadequate excretory, regulatory, and endocrine function of the kidneys. Both uremia and uremic syndrome have been used interchangeably to denote a very high plasma urea concentration that is the result of renal failure. The former denotation will be used for the rest of the article.
Renal functions include maintaining an acid–base balance; regulating fluid balance; regulating sodium, potassium, and other electrolytes; clearing toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pressure; production of various hormones, such as erythropoietin; and activation of vitamin D.
Assessment of kidney function occurs in different ways, using the presence of symptoms and signs, as well as measurements using urine tests, blood tests, and medical imaging.
Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both.
Chronic kidney disease (CKD) is a type of long-term kidney disease, in which either there is a gradual loss of kidney function occurs over a period of months to years, or abnormal kidney structure. Initially generally no symptoms are seen, but later symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications can relate to hormonal dysfunction of the kidneys and include high blood pressure, bone disease, and anemia. Additionally CKD patients have markedly increased cardiovascular complications with increased risks of death and hospitalization. CKD can lead to kidney failure requiring kidney dialysis or kidney transplantation.
Diabetic nephropathy, also known as diabetic kidney disease, is the chronic loss of kidney function occurring in those with diabetes mellitus. Diabetic nephropathy is the leading causes of chronic kidney disease (CKD) and end-stage renal disease (ESRD) globally. The triad of protein leaking into the urine, rising blood pressure with hypertension and then falling renal function is common to many forms of CKD. Protein loss in the urine due to damage of the glomeruli may become massive, and cause a low serum albumin with resulting generalized body swelling (edema) so called nephrotic syndrome. Likewise, the estimated glomerular filtration rate (eGFR) may progressively fall from a normal of over 90 ml/min/1.73m2 to less than 15, at which point the patient is said to have end-stage renal disease. It usually is slowly progressive over years.
Hypertensive kidney disease is a medical condition referring to damage to the kidney due to chronic high blood pressure. It manifests as hypertensive nephrosclerosis. It should be distinguished from renovascular hypertension, which is a form of secondary hypertension, and thus has opposite direction of causation.
Protein toxicity is the effect of the buildup of protein metabolic waste compounds, like urea, uric acid, ammonia, and creatinine. Protein toxicity has many causes, including urea cycle disorders, genetic mutations, excessive protein intake, and insufficient kidney function, such as chronic kidney disease and acute kidney injury. Symptoms of protein toxicity include unexplained vomiting and loss of appetite. Untreated protein toxicity can lead to serious complications such as seizures, encephalopathy, further kidney damage, and even death.
Hepatorenal syndrome (HRS) is a life-threatening medical condition that consists of rapid deterioration in kidney function in individuals with cirrhosis or fulminant liver failure. HRS is usually fatal unless a liver transplant is performed, although various treatments, such as dialysis, can prevent advancement of the condition.
Nephritic syndrome is a syndrome comprising signs of nephritis, which is kidney disease involving inflammation. It often occurs in the glomerulus, where it is called glomerulonephritis. Glomerulonephritis is characterized by inflammation and thinning of the glomerular basement membrane and the occurrence of small pores in the podocytes of the glomerulus. These pores become large enough to permit both proteins and red blood cells to pass into the urine. By contrast, nephrotic syndrome is characterized by proteinuria and a constellation of other symptoms that specifically do not include hematuria. Nephritic syndrome, like nephrotic syndrome, may involve low level of albumin in the blood due to the protein albumin moving from the blood to the urine.
Contrast-induced nephropathy (CIN) is a purported form of kidney damage in which there has been recent exposure to medical imaging contrast material without another clear cause for the acute kidney injury.
Phosphate nephropathy or nephrocalcinosis is an adverse renal condition that arises with a formation of phosphate crystals within the kidney's tubules. This renal insufficiency is associated with the use of oral sodium phosphate (OSP) such as C.B. Fleet's Phospho soda and Salix's Visocol, for bowel cleansing prior to a colonoscopy.
Glomerulonephrosis is a non-inflammatory disease of the kidney (nephrosis) presenting primarily in the glomerulus as nephrotic syndrome. The nephron is the functional unit of the kidney and it contains the glomerulus, which acts as a filter for blood to retain proteins and blood lipids. Damage to these filtration units results in important blood contents being released as waste in urine. This disease can be characterized by symptoms such as fatigue, swelling, and foamy urine, and can lead to chronic kidney disease and ultimately end-stage renal disease, as well as cardiovascular diseases. Glomerulonephrosis can present as either primary glomerulonephrosis or secondary glomerulonephrosis.
Sickle cell nephropathy is a type of kidney disease associated with sickle cell disease which causes kidney complications as a result of sickling of red blood cells in the small blood vessels. The hypertonic and relatively hypoxic environment of the renal medulla, coupled with the slow blood flow in the vasa recta, favors sickling of red blood cells, with resultant local infarction. Functional tubule defects in patients with sickle cell disease are likely the result of partial ischemic injury to the renal tubules.
Renal angina is a clinical methodology to risk stratify patients for the development of persistent and severe acute kidney injury (AKI). The composite of risk factors and early signs of injury for AKI, renal angina is used as a clinical adjunct to help optimize the use of novel AKI biomarker testing. The term angina from Latin and from the Greek ankhone ("strangling") are utilized in the context of AKI to denote the development of injury and the choking off of kidney function. Unlike angina pectoris, commonly caused due to ischemia of the heart muscle secondary to coronary artery occlusion or vasospasm, renal angina carries no obvious physical symptomatology. Renal angina was derived as a conceptual framework to identify evolving AKI. Like acute coronary syndrome which precedes or is a sign of a heart attack, renal angina is used as a herald sign for a kidney attack. Detection of renal angina is performed by calculating the renal angina index.
Andrew S. Levey is an American nephrologist who transformed chronic kidney disease (CKD) clinical practice, research, and public health by developing equations to estimate glomerular filtration rate (GFR), and leading the global standardization of CKD definition and staging.
The chronic kidney disease of the cat – also called chronic renal insufficiency or chronic renal failure (CRF) in the older literature – is an incurable, progressive disease characterized by a gradual decrease in the nephrons and thus to a decreasing function (insufficiency) of the kidneys. It is one of the most common causes of death in older domestic cats. In current literature, the term "kidney disease" is preferred to the term "renal insufficiency" because the disease initially progresses without any measurable decline in kidney function. Due to the different type of diet and the resulting metabolic peculiarities, the clinical picture and treatment sometimes differ significantly from chronic renal failure in humans.