A calculus (plural calculi), often called a stone, is a

concretion A concretion is a hard, compact mass of matter formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary rock or soil. Concretions are often ovoid or spherical in shape, although irregular ...

of material, usually mineral salts, that forms in an organ or duct of the body. Formation of calculi is known as lithiasis (). 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

urinary system The urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, co ...

are called urinary calculi and include

kidney stone Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine ...

s (also called renal calculi or nephroliths) and

bladder stone A bladder stone is a stone found in the urinary bladder. Signs and symptoms Bladder stones are small mineral deposits that can form in the bladder. In most cases bladder stones develop when the urine becomes very concentrated or when one is d ...

s (also called vesical calculi or cystoliths). They can have any of several compositions, including mixed. Principal compositions include oxalate and urate. * Calculi of the

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, altho ...

and

bile duct A bile duct is any of a number of long tube-like structures that carry bile, and is present in most vertebrates. Bile is required for the digestion of food and is secreted by the liver into passages that carry bile toward the hepatic duct. ...

s are called gallstones and are primarily developed from

bile salts Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts. Primary b ...

and cholesterol derivatives. * Calculi in the nasal passages (

rhinolith A rhinolith is a stone present in the nasal cavity. The word is derived from the roots ''rhino-'' and '' -lith'', literally meaning "nose stone". It is an uncommon medical phenomenon, not to be confused with dried nasal mucus. A rhinolith usually ...

s) are rare. * Calculi in the gastrointestinal tract (

enterolith An enterolith is a mineral concretion or calculus formed anywhere in the gastrointestinal system. Enteroliths are uncommon and usually incidental findings but, once found, they require at a minimum watchful waiting. If there is evidence of comp ...

s) can be enormous. Individual enteroliths weighing many pounds have been reported in horses. * Calculi in the

stomach The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...

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

tonsil The tonsils are a set of lymphoid organs facing into the aerodigestive tract, which is known as Waldeyer's tonsillar ring and consists of the adenoid tonsil, two tubal tonsils, two palatine tonsils, and the lingual tonsils. These organs play a ...

s are called tonsillar calculi (

tonsillolith Tonsil stones, also known as tonsilloliths, are mineralizations of debris within the crevices of the tonsils. When not mineralized, the presence of debris is known as chronic caseous tonsillitis (CCT). Symptoms may include bad breath. General ...

s). * Calculi in the

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated ...

s are called venous calculi (

phlebolith A phlebolith is a small local, usually rounded, calcification within a vein. These are very common in the veins of the lower part of the pelvis, and they are generally of no clinical importance. When located in the pelvis they are sometimes difficu ...

s). * Calculi in the skin, such as in

sweat gland Sweat glands, also known as sudoriferous or sudoriparous glands, , are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial su ...

s, are not common but occasionally occur. * Calculi in the navel are called

omphalolith An omphalolith or umbolith or omphalith or navel stone or umbilical concretion is a periumbilical mass that may form due to the accumulation of sebum and keratin. The colour is black or brown, and may be related to the skin type of the patient. It ...

s. 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

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar ...

( hypercalcaemia) that may cause

s, 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 The submandibular ganglion (or submaxillary ganglion in older texts) is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck. (The others are the otic ganglion, pterygopalatine ganglion, and ci ...

salivary gland. *

Enterolith An enterolith is a mineral concretion or calculus formed anywhere in the gastrointestinal system. Enteroliths are uncommon and usually incidental findings but, once found, they require at a minimum watchful waiting. If there is evidence of comp ...

s are a type of calculus found in the intestines of

animal Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in ...

s (mostly ruminants) and humans, and may be composed of

inorganic In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistr ...

organic Organic may refer to: * Organic, of or relating to an organism, a living entity * Organic, of or relating to an anatomical organ Chemistry * Organic matter, matter that has come from a once-living organism, is capable of decay or is the product ...

constituents. *

Bezoar A bezoar is a mass often found trapped in the gastrointestinal system, though it can occur in other locations. A pseudobezoar is an indigestible object introduced intentionally into the digestive system. There are several varieties of bezoar, s ...

s are lumps of indigestible material in the

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 kidney stones,

calcium oxalate Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydrate ...

is the most common mineral type (see

Nephrolithiasis Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine ...

Uric acid Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown o ...

is the second most common mineral type, but an '' in vitro'' study showed uric acid stones and crystals can promote the formation of calcium oxalate stones.

Pathophysiology

Stones can cause disease by several mechanisms: * 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: *

( kidney stones) ** Can cause hydronephrosis (swollen kidneys) and kidney failure ** Can predispose to pyelonephritis (kidney infections) ** Can progress to

urolithiasis Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urin ...

Urolithiasis Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urin ...

(

urinary bladder The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...

stones) ** Can progress to

bladder outlet obstruction Bladder outlet obstruction (or obstructive uropathy) occurs when urine is unable to flow from the kidneys through the ureters and out of the bladder through the urethra. Decreased flow of urine leads to swelling of the urinary tract, called hydron ...

Cholelithiasis A gallstone is a stone formed within the gallbladder from precipitated bile components. The term cholelithiasis may refer to the presence of gallstones or to any disease caused by gallstones, and choledocholithiasis refers to the presence of mig ...

(gallstones) ** Can predispose to

cholecystitis Cholecystitis is inflammation of the gallbladder. Symptoms include right upper abdominal pain, pain in the right shoulder, nausea, vomiting, and occasionally fever. Often gallbladder attacks (biliary colic) precede acute cholecystitis. The pain l ...

( gall bladder infections) and

ascending cholangitis Ascending cholangitis, also known as acute cholangitis or simply cholangitis, is inflammation of the bile duct, usually caused by bacteria ascending from its junction with the duodenum (first part of the small intestine). It tends to occur if t ...

(

biliary tree The biliary tract, (biliary tree or biliary system) refers to the liver, gallbladder and bile ducts, and how they work together to make, store and secrete bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids and co ...

infection) ** Can progress to

choledocholithiasis Common bile duct stone, also known as choledocholithiasis, is the presence of gallstones in the common bile duct (CBD) (thus '' choledocho-'' + ''lithiasis''). This condition can cause jaundice and liver cell damage. Treatments include choledochol ...

(gallstones in the bile duct) and gallstone pancreatitis (inflammation of the

pancreas The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine gland, i.e. it has both an ...

) * Gastric calculi can cause colic, obstruction, torsion, and necrosis.

Diagnosis

Diagnostic workup Medical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as diagnosis with the medical context being implicit. The information req ...

varies by the stone type, but in general: * Clinical history and physical examination * Imaging studies ** Some stone types (mainly those with substantial calcium content) can be detected on

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30 ...

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: * Healthy diet & exercise (promotes flow of energy & nutrition) * Drinking fluids (water &

electrolytes An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dis ...

like lemon juice, diluted vinegar eg. in pickles, salad dressings, sauces, soups, shrubs cocktail) * Surgery (

lithotomy Lithotomy from Greek for "lithos" (stone) and "tomos" ( cut), is a surgical method for removal of calculi, stones formed inside certain organs, such as the urinary tract (kidney stones), bladder (bladder stones), and gallbladder (gallstones), th ...

) * Medication / Antibiotics *

Extracorporeal shock wave lithotripsy Extracorporeal shockwave therapy (ESWT) is a non-invasive, out-patient alternative to surgery for those with many joint and tendon disorders. ESWT sends acoustic shock waves into bone or soft tissue, in effect reinjuring the area on a cellular l ...

(ESWL) for removal of calculi

History

The earliest operation for curing stones is given in the '' Sushruta Samhita'' (6th century BCE). The operation involved exposure and going up through the floor of the bladder.Lock, Stephen etc. (2001). ''The Oxford Illustrated Companion to Medicine''. USA: Oxford University Press. 836. . The care of this disease was forbidden to the

physicians A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

that had taken the

Hippocratic Oath The Hippocratic Oath is an oath of ethics historically taken by physicians. It is one of the most widely known of Greek medical texts. In its original form, it requires a new physician to swear, by a number of healing gods, to uphold specific e ...

because: * There was a high probability of intraoperative and postoperative surgical complication like infection or bleeding * The physicians would not perform surgery as in ancient cultures they were two different professions

Etymology

The word comes from Latin ''calculus'' "small stone", from ''calx'' "limestone, lime", probably related to Greek ''chalix'' "small stone, pebble, rubble",. which many trace to a Proto-Indo-European root for "split, break up". ''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.

References

External links

"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 {{Authority control Symptoms and signs Medical terminology