Calculus (medicine)

A calculus (pl.: calculi), often called a stone, is a concretion of material, usually mineral salts, that forms in an organ or duct of the body. Formation of calculi is known as lithiasis (/ˌlɪˈθaɪəsɪs/). Stones can cause a number of medical conditions.

Some common principles (below) apply to stones at any location, but for specifics see the particular stone type in question.

Calculi are not to be confused with gastroliths.

Types

• Calculi in the inner ear are called otoliths
• Calculi in the
  urate
  .
• Calculi of the gallbladder and bile ducts are called gallstones and are primarily developed from bile salts and cholesterol derivatives.
• Calculi in the nasal passages (rhinoliths) are rare.
• Calculi in the
  gastrointestinal tract (enteroliths
  ) can be enormous. Individual enteroliths weighing many pounds have been reported in horses.
• Calculi in the stomach are called gastric calculi (not to be confused with gastroliths which are exogenous in nature).
• Calculi in the salivary glands are called salivary calculi (sialoliths).
• Calculi in the
  tonsilloliths
  ).
• Calculi in the veins are called venous calculi (phleboliths).
• Calculi in the skin, such as in sweat glands, are not common but occasionally occur.
• Calculi in the navel are called omphaloliths.

Calculi are usually asymptomatic, and large calculi may have required many years to grow to their large size.

Cause

• From an underlying abnormal excess of the mineral, e.g., with elevated levels of
  kidney stones, dietary factors for gallstones
  .
• Local conditions at the site in question that promote their formation, e.g., local bacteria action (in kidney stones) or slower fluid flow rates, a possible explanation of the majority of
  salivary duct calculus occurring in the submandibular salivary gland
  .
• inorganic or organic
  constituents.
• Bezoars are lumps of indigestible material in the stomach and/or intestines; most commonly, they consist of hair (in which case they are also known as hairballs). A bezoar may form the nidus of an enterolith.

In

Stones can cause disease by several mechanisms:^[citation needed]

• Irritation of nearby tissues, causing pain, swelling, and inflammation
• Obstruction of an opening or duct, interfering with normal flow and disrupting the function of the organ in question
• Predisposition to infection (often due to disruption of normal flow)

A number of important medical conditions are caused by stones:^{[citation needed]}

• Nephrolithiasis (kidney
  stones)
  • Can cause hydronephrosis (swollen kidneys) and kidney failure
  • Can predispose to pyelonephritis (kidney infections)
  • Can progress to
    urolithiasis
• urinary bladder
  stones)
  • Can progress to bladder outlet obstruction
• Cholelithiasis
  (gallstones)
  • Can predispose to
    biliary tree
    infection)
  • Can progress to
    gallstone pancreatitis (inflammation of the pancreas
    )
• Gastric calculi can cause colic, obstruction, torsion, and necrosis.

Diagnosis

• Clinical history and physical examination
• Imaging studies:
  • Some stone types (mainly those with substantial calcium content) can be detected on X-ray and CT scan
  • Many stone types can be detected by
    ultrasound
• Factors contributing to stone formation (as in #Etiology) are often tested:
  • Laboratory testing can give levels of relevant substances in blood or urine
  • Some stones can be directly recovered (at surgery, or when they leave the body spontaneously) and sent to a laboratory for analysis of content

Treatment

Modification of predisposing factors can sometimes slow or reverse stone formation. Treatment varies by stone type, but, in general:^{[citation needed]}

• Healthy diet and exercise (promotes flow of energy and nutrition)
• Drinking fluids (water and
  electrolytes like lemon juice, diluted vinegar e.g. in pickles, salad dressings, sauces, soups, shrubs
  cocktail)
• Surgery (lithotomy)
• Medication / antibiotics
• Extracorporeal shock wave lithotripsy
  (ESWL) for removal of calculi

History

The earliest operation for curing stones is given in the Sushruta Samhita (6th century BCE).^[2] The operation involved exposure and going up through the floor of the bladder.^[2]

The care of this disease was forbidden to the

The word comes from Latin calculus "small stone", from calx "limestone, lime",^[3] probably related to Greek χάλιξ chalix "small stone, pebble, rubble",^[4] which many trace to a Proto-Indo-European language root for "split, break up".^[5] Calculus was a term used for various kinds of stones. In the 18th century it came to be used for accidental or incidental mineral buildups in human and animal bodies, like kidney stones and minerals on teeth.^[5]

See also

• Bezoar
• Calculus (dental)
• Lithotomy

References

External links

Wikimedia Commons has media related to Lithiasis.

• "The Little Treatise on the Medical Treatment of the Back and of Hemorrhoids" is a manuscript, from the 18th-century, in Arabic, which discusses the treatment of calculi