renal system disease
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What is the renal system?
The renal system, also known as the urinary system, consists of the kidneys, ureters, bladder, and urethra. The kidneys filter blood to eliminate waste and control the electrolyte composition of the blood, forming urine. Urine passes through the ureters to the bladder, where it is stored until it is eliminated via the urethra.
When the kidneys cannot conserve water or are not stimulated by the pituitary gland's ADH (antidiuretic hormone) to do so, the body loses water, leading to increased osmolality of body fluid. The kidneys are also involved in excreting hydrogen ions, and impaired function can cause their retention, resulting in renal acidosis.
Kidney failure, whether acute or chronic, refers to the partial or complete loss of kidney function. Kidney disease in children can include urinary tract infections, glomerulonephritis, and nephrotic syndrome.
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What is a renal system disease?
Renal system diseases are diseases and disorders that affect the human urinary system. These include infections, inflammations, benign and malignant tumors, and obstruction by calculi.
These disorders impact the elimination of waste and the conservation of the appropriate amount and quality of body fluid. Disturbances of the lower urinary tract can cause pain and distress, especially during pregnancy and in older adults. It can also cause progressive damage to the kidneys by interfering with the drainage of urine or by allowing bacterial infection to have access to the kidney.
Some nonexcretory functions that the kidneys perform include secreting renin, which helps control blood pressure and electrolyte balance; erythropoietin, which is important for the formation of red blood cells; and 1,25-dihydroxycholecalciferol, the active form of vitamin D.
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What are some common types of renal system diseases?
The renal system, or urinary system, can be affected by various diseases and disorders that impact waste elimination and fluid conservation.
Common types of renal system diseases:
* Kidney stones Solid particles that form in the kidneys from an excessive concentration of mineral salts. Large stones can cause severe pain, obstruction, and infection.
* Glomerulonephritis Also known as nephritis or Bright’s disease, this condition involves inflammation of the glomeruli, often following a streptococcal infection. It can lead to kidney damage and renal failure.
* Pyelonephritis An infection and inflammation of the kidney tissue and renal pelvis, typically caused by bacteria. It can be acute or chronic, leading to tissue damage and impaired kidney function.
* Diabetic nephropathy Deterioration of kidney function as a complication of diabetes mellitus. It is characterized by increased protein excretion, high blood pressure, and reduced filtration rate.
* Polycystic kidney disease A hereditary disorder marked by the growth of cysts in the kidneys, leading to reduced kidney function or renal failure.
* Renal cell carcinoma A type of kidney cancer that appears to be caused by both genetic and environmental factors.
* Vascular disease Primary vascular disease can cause kidney damage. Malignant hypertension can cause rapid destruction of renal substance.7 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How do renal system diseases affect the body?
Renal system diseases disrupt the body's waste elimination and fluid balance, leading to various complications. Chronic renal failure, often stemming from conditions like pyelonephritis or glomerulonephritis, results in progressive nephron damage, impairing the kidney's filtration capabilities.
Uremia, or increased urea concentration in the blood, can occur, causing symptoms from thirst to coma. The retention of toxins and imbalances in electrolytes, such as salt, potassium, and calcium, can lead to acidosis, bone disease, and cardiovascular issues like hypertension. Severe hypertension can further damage the kidneys, creating a destructive cycle. Anemia, caused by reduced erythropoietin production, is also common.
In advanced stages, treatment includes strict diets, dialysis, or kidney transplantation.
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What are some symptoms of renal system diseases?
Symptoms of renal system diseases vary widely based on the specific condition but often include changes in urination, such as increased frequency, pain, or blood in the urine. Other common symptoms include swelling (edema) in the face and ankles, particularly in the case of glomerulonephritis.
Additional signs can be:
* Pain in the loins
* High blood pressure
* Loss of appetite, nausea, vomiting, and diarrheaIn severe cases, renal failure can lead to confusion, muscle twitching, or even coma. Kidney stones may cause intense pain in the abdomen and groin. Some individuals, however, might experience no obvious symptoms, highlighting the importance of regular medical checkups for early detection and management.
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How can renal system diseases be diagnosed and treated?
To diagnose renal system diseases, doctors use imaging techniques like X-rays, ultrasound, and MRI to view the kidneys, pelvis, and ureters. These methods help identify issues such as stones, tumors, or obstructions. Kidney function tests, including urine analysis and clearance tests, assess the kidney's ability to filter and conserve water.
Dialysis and kidney transplantation can help address renal failure. Dialysis involves filtering blood to remove waste, while transplantation replaces the diseased kidney with a healthy one. Treatment for acute renal failure includes managing fluid intake, diet, and electrolyte balance, and addressing the underlying cause.
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renal system disease, any of the diseases or disorders that affect the human urinary system. They include benign and malignant tumours, infections and inflammations, and obstruction by calculi.
Diseases can have an impact on the elimination of wastes and on the conservation of an appropriate amount and quality of body fluid. Many of the manifestations of renal disease can be accounted for in terms of disturbance of these two functions, and the alleviation of symptoms in those renal diseases that cannot be cured depends on knowledge of how these two functions are affected.
The eliminatory process does not, of course, end with the formation of urine; the urine has to pass down the ureters to the bladder, be stored there, and voided, usually under voluntary control. The whole mechanism can be deranged by structural changes in the lower urinary tract, by infection, or by neurological disorders that lead to abnormal emptying of the bladder. Disturbance of the lower urinary tract is an important cause of pain and distress, notably during pregnancy and in the elderly; and it can lead to serious and progressive damage to the kidneys, either by interfering with the drainage of urine or by allowing bacterial infection to have access to the kidney.
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Functional aspects
Effects of abnormal renal function on body fluid
Renal disease in its diverse forms can lead to bodily deficits or excesses of water, sodium, potassium, and magnesium, and also to protein deficits occasioned by great losses of protein in the urine. Inability of the kidney to function normally may lead to retention in the blood of the waste products of protein metabolism, such as urea and uric acid, and of other nitrogenous compounds such as creatinine. There may be abnormally high levels of phosphates in the blood, which in turn can lead (for reasons about which there is still some disagreement) to low blood levels of calcium. The calcium deficiency can cause tetany, a condition marked by muscular spasms and pain, and calcium may be lost from the bones in the process of restoring normal calcium levels in the blood and tissue fluid. For descriptive purposes, changes in volume, changes in composition, and protein depletion of renal origin will be discussed separately, but these disturbances can and often do coexist.
Though body fluid is most readily apparent in the bloodstream, it is present, and in larger amounts, in the tissues, both between the cells (interstitial fluid) and within them (intracellular fluid). Extracellular fluids, which include interstitial fluid and blood plasma, amount to 25 percent of body weight and contain sodium as their predominant cation (positive ion; metals and hydrogen in solution are cations). Intracellular fluids, amounting to 33 percent of body weight, have potassium as their predominant cation. These various “compartments” of body fluid are in osmotic equilibrium, so that if solute (e.g., sodium chloride) is added to the extracellular compartment so as to increase the concentration of the extracellular solution, water will join it to reduce the concentration, and that compartment will increase. An increase in extracellular fluid, if it is considerable, may be clinically apparent as edema, a swelling of the tissues by fluid, which can usually be displaced by firm pressure. Edema is present in acute inflammation of the kidney (nephritis), in protein deficiency of renal origin, and in chronic nephritis complicated by heart failure associated with abnormally high blood pressure; a factor common to all these states is failure of the kidneys to excrete sodium and water in adequate amounts.
The kidneys in such edematous states need not themselves be diseased; for example, normal kidneys, in a patient with heart failure, may retain sodium when handicapped in their function by poor circulation and by abnormal amounts of sodium-retaining hormones, such as aldosterone. Increase in extracellular fluids is the only volume change that is both common and easily discernible in renal disease, but the opposite condition, sodium depletion or clinical dehydration, is more commonly the result of vomiting and diarrhea when they are complications of terminal renal disease. Sodium and water depletion can be recognized by a lack of elasticity in the superficial tissues and by poor filling of the blood vessels, as well as by signs of impaired circulation, including a fall in blood pressure and an increase in pulse rate. Though changes in intracellular fluid volume occur in some diseases, especially when the potassium content of the body is affected, there is no easy way of detecting them.