Casts Health Dictionary

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Casts: From 1 Different Sources

Casts of hollow organs are found in various diseases. Membraneous casts of the air passages are found in diphtheria and in one form of bronchitis, and are sometimes coughed up entire. Casts of the interior of the bowels are passed in cases of mucous colitis associated with constipation, and casts of the microscopic tubules in the kidneys passed in the urine form one of the surest signs of glomerulonephritis. (See KIDNEYS, DISEASES OF.)
Health Source: Medical Dictionary
Author: Health Dictionary

Plaster Of Paris

A form of calcium sulphate, which, after soaking in water, sets ?rmly. For this reason it is widely used as a form of splinting in the treatment of fractures, for producing casts to immobilise parts of the body, and for dental models. Splints are made with bandages impregnated with plaster and a suitable adhesive. Its great advantage, compared with an ordinary splint, is that it can be moulded to the shape of the limb.... plaster of paris

Cast

A rigid casing applied to a limb or other part of the body to hold a broken bone or dislocated joint in position as it heals.

Most casts are made of bandages, impregnated with plaster of Paris, which are applied wet and harden as they dry.... cast

Crush Syndrome

A condition in which kidney failure occurs in patients who have been the victims of severe crushing accidents (see also KIDNEYS). The fundamental injury is damage to muscle. The limb swells. The blood volume falls. Blood UREA rises; there is also a rise in the POTASSIUM content of the blood. Urgent treatment in an intensive therapy unit is required and renal dialysis may well be necessary. The patient may survive; or die with renal failure. Post-mortem examination shows degeneration of the tubules of the kidney, and the presence in them of pigment casts.... crush syndrome

Urine

Waste substances resulting from the body’s metabolic processes, selected by the KIDNEYS from the blood, dissolved in water, and excreted. Urine is around 96 per cent water, the chief waste substances being UREA (approximately 25 g/1), common salt (approximately 9 g/l), and phosphates and sulphates of potassium, sodium, calcium, and magnesium. There are also small amounts of URIC ACID, ammonia, creatinine, and various pigments. Poisons, such as MORPHINE, may be excreted in the urine; and in many infections, such as typhoid fever (see ENTERIC FEVER), the causative organism may be excreted.

The daily urine output varies, but averages around 1,500 ml in adults, less in children. The ?uid intake and ?uid output (urine and PERSPIRATION) are interdependent, so as to maintain a relatively constant ?uid balance. Urine output is increased in certain diseases, notably DIABETES MELLITUS; it is diminished (or even temporarily stopped) in acute glomerulonephritis (see under KIDNEYS, DISEASES OF), heart failure, and fevers generally. Failure of the kidneys to secrete any urine is known as anuria, while stoppage due to obstruction of the ureters (see URETER) by stones, or of the URETHRA by a stricture, despite normal urinary secretion, is known as urinary retention.

Normal urine is described as straw- to amber-coloured, but may be changed by various diseases or drugs. Chronic glomerulonephritis or poorly controlled diabetes may lead to a watery appearance, as may drinking large amounts of water. Consumption of beetroot or rhubarb may lead to an orange or red colour, while passage of blood in the urine (haematuria) results in a pink or bright red appearance, or a smoky tint if just small amounts are passed. A greenish urine is usually due to BILE, or may be produced by taking QUININE.

Healthy urine has a faint aroma, but gives o? an unpleasant ammoniacal smell when it begins to decompose, as may occur in urinary infections. Many foods and additives give urine a distinctive odour; garlic is particularly characteristic. The density or speci?c gravity of urine varies normally from 1,015 to 1,025: a low value suggests chronic glomerulonephritis, while a high value may occur in uncontrolled diabetes or during fevers. Urine is normally acidic, which has an important antiseptic action; it may at times become alkaline, however, and in vegetarians, owing to the large dietary consumption of alkaline salts, it is permanently alkaline.

Chemical or microscopical examination of the urine is necessary to reveal abnormal drugs, poisons, or micro-organisms. There are six substances which must be easily detectable for diagnostic purposes: these are ALBUMINS, blood, GLUCOSE, bile, ACETONE, and PUS and tube-casts (casts from the lining of the tubules in the kidneys). Easily used strip tests are available for all of these, except the last.

Excess of urine It is important to distinguish urinary frequency from increase in the total amount of urine passed. Frequency may be due to reduced bladder capacity, such as may be caused by an enlarged PROSTATE GLAND, or due to any irritation or infection of the kidneys or bladder, such as CYSTITIS or the formation of a stone. Increased total urinary output, on the other hand, is often a diagnostic feature of diabetes mellitus. Involuntary passage of urine at night may result, leading to bed wetting, or NOCTURNAL ENURESIS in children. Diagnosis of either condition, therefore, means that the urine should be tested for glucose, albumin, gravel (fragments of urinary calculi), and pus, with appropriate treatment.... urine

Biomechanical Engineering

A discipline that applies engineering methods and principles to the body to explain how it functions and to treat disorders. Practical applications include the design of

artificial joints and heart valves, plaster casts, and kidney dialysis machines.... biomechanical engineering

Kidney Function Tests

Tests performed to investigate kidney disorders.

Urinalysis is a simple test in which a urine sample is examined under a microscope for blood cells, pus cells, and casts (cells and mucous material that accumulate in the tubules of the kidneys and pass into the urine).

Urine may be tested for substances, such as proteins, that leak into the urine when the kidneys are damaged.

Kidney function can be assessed by measuring the concentration in the blood of substances, such as urea and creatinine, that the kidneys normally excrete.

Kidney function may also be assessed by kidney imaging techniques.... kidney function tests

Orthopaedics

The branch of surgery concerned with disorders of the bones and joints and their associated muscles, tendons, and ligaments. Procedures include setting broken bones and applying casts; treating dislocations, slipped discs, arthritis, and back problems; treating bone tumours and birth defects of the skeleton; and repairing or replacing hip, knee, or finger joints.... orthopaedics

Cast Nephropathy

(myeloma kidney) a complication of multiple myeloma seen in approximately half of those who have renal disease. The casts typically involve the distal convoluted and collecting tubules and often have a fractured or crystalline appearance. They are frequently surrounded by multinucleate giant cells. Deposition of the casts is associated with progressive renal failure.... cast nephropathy

Compartment Syndrome

the condition that results from swelling of the muscles in a *compartment of a limb, which raises the pressure within the compartment so that the blood supply to the muscle is cut off, causing *ischaemia and further swelling. If it persists, the muscles and nerves within the compartment die, leading to *Volkmann’s contracture (when the forearm is affected). Causes are trauma, damage to blood vessels, reperfusion after ischaemia, and tight casts or bandages. Treatment is to release any tight dressings and to divide the fascia surrounding the compartment to relieve the pressure (see fasciotomy). This should be performed urgently, within six hours from the onset of symptoms, to prevent permanent damage.... compartment syndrome

Curschmann’s Spirals

elongated *casts of the smaller bronchi, which are coughed up in bronchial asthma. They unroll to a length of 2 cm or more and have a central core ensheathed in mucus and cell debris. [H. Curschmann (1846–1910), German physician]... curschmann’s spirals

Glomerulonephritis

(glomerular nephritis, GN) n. inflammation of the glomeruli, although in practice the term is used for a number of glomerular conditions lacking microscopical signs of inflammation. For instance, *membranous nephropathy is often referred to as membranous glomerulonephritis. GN may be a primary disease, restricted in its clinical manifestations to the kidney, or part of a multisystem disorder, such as systemic *lupus erythematosus or *vasculitis. Its presentation may be acute, with a *nephritic or *nephrotic syndrome; subacute, with rapidly declining renal function over a period of days or weeks; or chronic, with signs of the disease picked up on routine medical examination. Abnormalities of urine analysis are to be expected, with blood, protein, and casts present in variable amounts. Arterial hypertension is a common associated finding. GN is classified according to the different patterns of histological injury seen on renal biopsy specimens; these are examined by light and electron microscopy and by immunofluorescent studies.... glomerulonephritis

Granular Cast

a cellular *cast derived from a kidney tubule. In certain kidney diseases, notably acute *glomerulonephritis, abnormal collections of renal tubular cells are shed from the kidney, often as a cast of the tubule. The casts can be observed on microscopic examination of the centrifuged deposit of a specimen of urine. Their presence in the urine indicates continued activity of the disease.... granular cast

Nephritic Syndrome

generalized inflammation of the glomeruli of the kidneys resulting in a reduction in *glomerular filtration rate, with mild oedema and hypertension resulting from renal salt and water retention. Urine analysis shows the presence of proteinuria and microscopic haematuria with red cell casts. Common and usually self-limiting causes are *Berger’s nephropathy and poststreptococcal glomerulonephritis. Less common but more serious causes of the nephritic syndrome are the vasculitides (see vasculitis) and *Goodpasture’s disease, which, untreated, usually prove fatal.... nephritic syndrome

Retinoscope

n. an instrument used to determine the power of spectacle lens required to correct *refractive errors of the eye. It is held in the hand and casts a beam of light into the subject’s eye. The examiner looks along the beam and sees the reflection in the subject’s pupil. By interpreting the way the reflection moves as the instrument is moved, and by altering this by lenses held in the other hand near the subject’s eye, the examiner is able to determine the degree of refractive error. —retinoscopy n.... retinoscope

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