Kidney stones or
renal calculi (from
LatinLatin is an Italic language originally spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe...
ren, renes, "kidney" and
calculi, "pebbles") are solid concretions or
calculiA calculus is a stone that forms in an organ or duct of the body. Formation of calculi is known as lithiasis...
(
crystalA crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is crystallography...
aggregations) formed in the
kidneyThe kidneys are paired organs, which have the production of urine as their primary function. Kidneys are seen in many types of animals, including vertebrates and some invertebrates. They are part of the urinary system, but have several secondary functions concerned with homeostatic functions. ...
s from dissolved
urinaryUrine is a liquid waste product of the body secreted by the kidneys by a process of filtration from blood called urination and excreted through the urethra. Cellular metabolism generates numerous waste compounds, many rich in nitrogen, that require elimination from the bloodstream...
mineralsDietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules...
.
Nephrolithiasis (from
GreekGreek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical...
nephros, "kidney" and λιθoς (
lithos, "stone")) refers to the condition of having kidney stones.
UrolithiasisUrolithiasis is the condition where urinary calculi are formed in the urinary tract....
refers to the condition of having calculi in the urinary tract (which also includes the kidneys), which may form or pass into the
urinary bladderIn anatomy, the urinary bladder is the organ that collects urine excreted by the kidneys prior to disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
. Ureterolithiasis is the condition of having a calculus in the
ureterIn human anatomy, the ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually long....
, the tube connecting the kidneys and the bladder. The term
bladder stonesBladder stones or uroliths are a common occurrence in animals, especially in domestic animals such as dogs and cats. Occurrence in other species, including tortoises, have been reported as well. The stones form in the urinary bladder in varying size and numbers secondary to infection, dietary...
usually applies to urolithiasis of the bladder in non-human animals such as dogs and cats.
Kidney stones typically leave the body by passage in the urine stream, and many stones are formed and passed without causing symptoms. If stones grow to sufficient size before passage—on the order of at least 2-3 millimeters—they can cause obstruction of the ureter. The resulting obstruction causes dilation or stretching of the upper ureter and
renal pelvisThe renal pelvis is the funnel-like dilated proximal part of the ureter in the kidney.It is the point of convergence of two or three major calyces...
(the part of the kidney where the urine collects before entering the ureter) as well as muscle spasm of the ureter, trying to move the stone. This leads to
painPhysical Pain is the unpleasant feeling common to a headache and a stubbed toe. It typically consists of negative affect and aversion, and has location, duration, intensity and a distinctive quality...
, most commonly felt in the
flankFlank may refer to:* Flank, the side of either a horse or a military unit*Flanking maneuver in military tactics* Flank , the waveform edge formed when a signal goes high or low...
, lower abdomen and
groinIn human anatomy, the groin areas are the two creases at the junction of the torso with the legs, on either side of the pubic area. A pulled groin muscle usually refers to a painful injury sustained by straining the hip adduction muscle....
(a condition called
renal colicRenal colic is a type of pain commonly caused by kidney stones.-Presentation:The pain typically begins in the loin region and often radiates to the hypochondrium or the groin. The pain is often colicky due to ureteric peristalsis, but may be constant...
). Renal colic can be associated with
nauseaNausea is the sensation of unease and discomfort in the stomach with an urge to vomit.-Causes:...
and
vomitingVomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Undesired vomiting may result from many causes, ranging from gastritis or poisoning to brain tumors, or elevated intracranial pressure...
. There can be blood in the urine, visible with the naked eye or under the microscope (macroscopic or
microscopic hematuriaMicroscopic hematuria is a medical condition in which urine contains small amounts of blood. Blood quantity is too low to change the color of the urine . While not dangerous in itself, it can be a symptom of a chronic kidney disease, such as IgA nephropathy, which should be monitored by a doctor....
) due to damage to the
lining of the urinary tractThe urothelium is the tissue layer that lines much of the urinary tract, including the renal pelvis, the ureters, the bladder, and parts of the urethra.-Functions:...
.
There are several types of kidney stones based on the type of crystals of which they consist. The majority are
calcium oxalateCalcium oxalate is a chemical compound that forms needle-shaped crystals. Its chemical formula is CaC
2O
4 or Ca
2.-Occurrence:...
stones, followed by
calcium phosphateCalcium phosphate is the name given to a family of minerals containing calcium ions together with orthophosphates , metaphosphates or pyrophosphates and occasionally hydrogen or hydroxide ions.It is the principal form of calcium found in bovine milk...
stones. More rarely,
struviteStruvite is a phosphate mineral with formula: . Struvite crystallizes in the orthorhombic system as white to yellowish or brownish-white pyramidal crystals or in platey mica-like forms. It is a soft mineral with Mohs hardness of 1.5 to 2 and has a low specific gravity of 1.7...
stones are produced by
ureaUrea or carbamide is an organic compound with the chemical formula
2CO. The molecule has two amine residues joined by a carbonyl functional group....
-splitting
bacteriaThe bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
in people with
urinary tract infectionA urinary tract infection is a bacterial infection that affects any part of the urinary tract.The main causitive agent is:Escherichia coli. Although urine contains a variety of fluids, salts, and waste products, it usually does not have bacteria in it. When bacteria get into the bladder or kidney...
s, and people with certain metabolic abnormalities may produce
uric acidUric acid is an organic compound of carbon, nitrogen, oxygen and hydrogen with the formula C
5H
4N
4O
3.-Biology:...
stones or
cystineCystine is a dimeric amino acid formed by the oxidation of two cysteine residues which covalently link to make a disulfide bond. This organosulfur compound has the formula
2. It is a colorless solid, and melts at 247-249 °C...
stones.
The
diagnosisDiagnosis is the identification of the nature of anything, either by process of elimination or other analytical methods...
of a kidney stone can be confirmed by
radiologicalRadiology is the branch or specialty of medicine that deals with the study and application of imaging technology like x-ray and radiation to diagnosing and treating disease....
studies or ultrasound examination; urine tests and
blood testA blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a needle, or via fingerprick....
s are also commonly performed. When a stone causes no symptoms,
watchful waitingWatchful waiting is an approach to a medical problem in which time is allowed to pass before medical intervention or therapy is used. During this time, repeated testing may be performed....
is a valid option. In other cases, pain control is the first measure, using for example non-steroidal anti-inflammatory drugs or opioids. Using soundwaves, some stones can be shattered into smaller fragments (this is called extracorporeal shock wave lithotripsy). Sometimes a procedure is required, which can be through a tube into the
urethraIn anatomy, the urethra is a tube which connects the urinary bladder to the outside of the body. The urethra has an excretory function in both sexes to pass urine to the outside, and also a reproductive function in the male, as a passage for semen.The external urethral sphincter is a striated...
, bladder and ureter (
ureteroscopyUreteroscopy is an examination of the upper urinary tract, usually performed with an endoscope that is passed through the urethra, bladder, and then directly into the ureter...
), or a keyhole or open surgical approach from the kidney's side. Sometimes, a tube may be left in the ureter (a
ureteric stentA ureteral stent, sometimes as well called ureteric stent, is a thin tube inserted into the ureter to prevent or treat obstruction of the urine flow from the kidney. The length of the stents used in adult patients varies between 24 to 30 cm. Additionally, stents come in differing diameters or...
) to prevent the recurrence of pain. Preventive measures are often advised such as drinking sufficient amounts of water, although the effect of many dietary interventions has not been rigorously studied.
Causes
Kidney stones can be due to underlying metabolic conditions, such as
renal tubular acidosisRenal tubular acidosis is a medical condition that involves an accumulation of acid in the body due to a failure of the kidneys to appropriately acidify the urine. When blood is filtered by the kidney, the filtrate passes through the tubules of the nephron, allowing for exchange of salts, acid...
,
Dent's diseaseDent's disease is a rare X-linked recessive inherited condition that affects the kidney. It is one cause of Fanconi syndrome, and is characterized by tubular proteinuria, hypercalciuria, calcium nephrolithiasis, nephrocalcinosis and chronic renal failure."Dent's disease" is often used to describe...
,
hyperparathyroidismHyperparathyroidism is overactivity of the parathyroid glands resulting in excess production of parathyroid hormone . The parathyroid hormone regulates calcium and phosphate levels and helps to maintain these levels...
and
medullary sponge kidneyAlso known as Cacchi-Ricci disease, Medullary sponge kidney is a congenital disorder of the kidneys characterized by a cystic dilatation of the collecting tubules in one or both kidneys. It has been estimated to occur with a prevalence of between 1 in every 5,000-10,000 individuals in a population...
. Many health facilities will screen for such problems in patients with recurrent kidney stones. This is typically done with a 24 hour urine collection that is chemically analyzed for deficiencies and excesses that promote stone formation. Kidney stones are also more common in patients with
Crohn's diseaseCrohn's disease is an inflammatory disease of the intestines that may affect any part of the gastrointestinal tract from anus to mouth, causing a wide variety of symptoms...
.
There has been some evidence that
water fluoridationWater fluoridation is the controlled addition of fluoride to a public water supply to reduce tooth decay. Fluoridated water has fluoride at a level that is effective for preventing cavities; this can occur naturally or by adding fluoride...
may increase the risk of kidney stone formation. In one study, patients with symptoms of
skeletal fluorosisSkeletal fluorosis is a bone disease caused by excessive consumption of fluoride. In advanced cases, skeletal fluorosis causes pain and damage to bones and joints.-Causes:...
were 4.6 times as likely to develop kidney stones. However,
fluorideFluoride is the anion F
−, the reduced form of fluorine. Both organic and inorganic compounds containing the element fluorine are sometimes called fluorides. Fluoride, like other halides, is a monovalent ion . Its compounds often have properties that are distinct relative to other...
may also be an
inhibitor of urinary stone formation.
A 1998 paper in the
Archives of Internal MedicineThe Archives of Internal Medicine is an international peer-reviewed professional medical journal published twice a month by the American Medical Association...
examined the sources of a widely-held belief in the medical community that
vitamin CVitamin C or L-ascorbic acid is an essential nutrient for humans, in which it functions as a vitamin. Ascorbate is required for a range of essential metabolic reactions in all animals and plants...
can cause kidney stones, and found it to be based on several circular references, ultimately attributing the belief to a wider pattern of skepticism regarding efficacy of vitamin supplements. A more recent study suggested a causal relationship may exist, but it was not conclusive.
The American Urological Association has projected that increasing global temperatures will lead to greater future prevalence of kidney stones, notably by expanding the "kidney stone belt" of the southern United States
AstronautAn astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....
s seem to show a higher risk of developing kidney stones during or after long duration space flights.
Calcium oxalate stones
The most common type of kidney stone is composed of
calcium oxalateCalcium oxalate is a chemical compound that forms needle-shaped crystals. Its chemical formula is CaC
2O
4 or Ca
2.-Occurrence:...
crystals, occurring in about 80% of cases, and the factors that promote the precipitation of crystals in the urine are associated with the development of these stones.
Common sense has long held that consumption of too much
calciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust...
could promote the development of calcium kidney stones. However, current evidence suggests that the consumption of low-calcium diets is actually associated with a higher overall risk for the development of kidney stones. This is perhaps related to the role of calcium in binding ingested
oxalateAn oxalate is the deprotonated, charged form of oxalic acid or an ester of oxalic acid. The oxalate anion has the chemical formula C2O42−, also written...
in the gastrointestinal tract. As the amount of calcium intake decreases, the amount of oxalate available for absorption into the bloodstream increases; this oxalate is then excreted in greater amounts into the urine by the kidneys. In the urine, oxalate is a very strong promoter of calcium oxalate precipitation, about 15 times stronger than calcium.
Uric acid (urate)
About 5–10% of all stones are formed from
uric acidUric acid is an organic compound of carbon, nitrogen, oxygen and hydrogen with the formula C
5H
4N
4O
3.-Biology:...
.
Uric acid stones form in association with conditions that cause
hyperuricosuriaHyperuricosuria is a medical term referring to the presence of excessive amounts of uric acid in the urine. Notable direct causes of hyperuricosuria are dissolution of uric acid crystals in the kidneys or urinary bladder, and hyperuricemia...
with or without high
blood serumIn blood, the serum is the component that is neither a blood cell nor a clotting factor; it is the blood plasma with the fibrinogens removed. Serum includes all proteins not used in blood clotting and all the electrolytes, antibodies, antigens, hormones, and any exogenous substances .The study of...
uric acid levels (
hyperuricemiaHyperuricemia is a level of uric acid in the blood that is abnormally high. In humans, the upper end of the normal range is 360 µmol/L for women and 400 µmol/L for men.-Causes:...
); and with acid/base
metabolismMetabolism is the set of chemical reactions that occur in living organisms to maintain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories. Catabolism breaks down organic matter,...
disorders where the urine is excessively acidic (low
pHpH is a measure of the acidity or basicity of a solution. It is defined as the cologarithm of the activity of dissolved hydrogen ions . Hydrogen ion activity coefficients cannot be measured experimentally, so they are based on theoretical calculations...
) resulting in uric acid precipitation. A diagnosis of uric acid nephrolithiasis is supported if there is a radiolucent stone, a persistent undue urine acidity, and uric acid crystals in fresh urine samples.
Other types
Other types of kidney stones are composed of
struviteStruvite is a phosphate mineral with formula: . Struvite crystallizes in the orthorhombic system as white to yellowish or brownish-white pyramidal crystals or in platey mica-like forms. It is a soft mineral with Mohs hardness of 1.5 to 2 and has a low specific gravity of 1.7...
(
magnesiumMagnesium is a chemical element with the symbol Mg, atomic number 12 and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the earth's crust by mass, although ninth in the Universe as a whole...
,
ammoniumThe ammonium cation is a positively charged polyatomic cation of the chemical formula NH. It has a formula weight of 18.05 and is formed by the protonation of ammonia...
and
phosphateA phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...
);
calcium phosphateCalcium phosphate is the name given to a family of minerals containing calcium ions together with orthophosphates , metaphosphates or pyrophosphates and occasionally hydrogen or hydroxide ions.It is the principal form of calcium found in bovine milk...
; and
cystineCystine is a dimeric amino acid formed by the oxidation of two cysteine residues which covalently link to make a disulfide bond. This organosulfur compound has the formula
2. It is a colorless solid, and melts at 247-249 °C...
.
The formation of struvite stones is associated with the presence of
ureaUrea or carbamide is an organic compound with the chemical formula
2CO. The molecule has two amine residues joined by a carbonyl functional group....
-splitting bacteria, most commonly
Proteus mirabilisProteus mirabilis is a Gram-negative, facultatively anaerobic bacterium. It shows swarming motility, and urease activity. P. mirabilis causes 90% of all 'Proteus' infections in humans.-Diagnosis:...
(but also
Klebsiella,
Serratia,
Providencia species). These organisms are capable of splitting urea into
ammoniaAmmonia is a compound of nitrogen and hydrogen with the formula NH
3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers...
, decreasing the acidity of the urine and resulting in favorable conditions for the formation of struvite stones. Struvite stones are always associated with urinary tract infections.
The formation of
calcium phosphateCalcium phosphate is the name given to a family of minerals containing calcium ions together with orthophosphates , metaphosphates or pyrophosphates and occasionally hydrogen or hydroxide ions.It is the principal form of calcium found in bovine milk...
stones is associated with conditions such as
hyperparathyroidismHyperparathyroidism is overactivity of the parathyroid glands resulting in excess production of parathyroid hormone . The parathyroid hormone regulates calcium and phosphate levels and helps to maintain these levels...
and renal tubular acidosis.
Formation of cystine stones is uniquely associated with people suffering from
cystinuriaCystinuria is an inherited autosomal recessive metabolic disorder that is characterized by the formation of cystine stones in the kidneys, ureter, and bladder.-Signs and symptoms:In acidic pH, cystine crystals are formed in the urine....
, who accumulate
cystineCystine is a dimeric amino acid formed by the oxidation of two cysteine residues which covalently link to make a disulfide bond. This organosulfur compound has the formula
2. It is a colorless solid, and melts at 247-249 °C...
in their urine. Cystinuria can be caused by Fanconi's syndrome.
Urolithiasis has also been noted to occur in the setting of therapeutic drug use, with crystals of drug forming within the renal tract in some patients currently being treated with
IndinavirIndinavir is a protease inhibitor used as a component of highly active antiretroviral therapy to treat HIV infection and AIDS.-History:...
,
SulfadiazineSulfadiazine is a sulfonamide antibiotic.-Uses:It eliminates bacteria that cause infections by stopping the production of folic acid inside the bacterial cell, and is commonly used to treat urinary tract infections ....
or
TriamtereneTriamterene is a potassium-sparing diuretic used in combination with thiazide diuretics for the treatment of hypertension and edema.- Mechanism of action :...
.
Symptoms
Symptoms of kidney stones include:
- Colicky pain
Renal colic is a type of pain commonly caused by kidney stones.-Presentation:The pain typically begins in the loin region and often radiates to the hypochondrium or the groin. The pain is often colicky due to ureteric peristalsis, but may be constant...
: "loin to groin". Often described as "the worst pain [...] ever experienced".
- Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
: blood in the urine, due to minor damage to inside wall of kidney, ureter and/or urethra.
- Pyuria
In medicine, Pyuria refers to urine which contains pus. Defined as the presence of 4 or more neutrophils per high power field of unspun, voided mid-stream urine. It can be sign of a bacterial urinary tract infection...
: pus in the urine.
- Dysuria
In medicine, specifically urology, dysuria refers to painful urination.Difficult urination is also sometimes described as dysuria.It is one of a constellation of irritative bladder symptoms, which includes urinary frequency and haematuria.-Causes:...
: burning on urination when passing stones (rare). More typical of infection.
- Oliguria
Oliguria is the decreased production of urine. The decreased production of urine may be a sign of dehydration, renal failure, hypovolemic shock or urinary obstruction/urinary retention....
: reduced urinary volume caused by obstruction of the bladder or urethra by stone, or extremely rarely, simultaneous obstruction of both ureters by a stone.
- Abdominal distension
Abdominal distension can be a sign of many other conditions, including:* Coeliac disease* Refractory sprue* Tropical sprue* Small bowel bacterial overgrowth syndrome* Kwashiorkor* Eosinophilic gastroenteritis* Giardiasis...
.
- Nausea
Nausea is the sensation of unease and discomfort in the stomach with an urge to vomit.-Causes:...
/vomitingVomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Undesired vomiting may result from many causes, ranging from gastritis or poisoning to brain tumors, or elevated intracranial pressure...
: embryological link with intestine stimulates the vomiting centerThe area postrema is a part of the brain that controls vomiting. It was discovered in 1953 by Utah Pharmacologists Herbert L. Borison and S. C. Wang .-Location:It is located in the lateral reticular formation of the medulla oblongata...
.
- Fever and chills.
- Hydronephrosis
Hydronephrosis is distension and dilation of the renal pelvis and calyces, usually caused by obstruction of the free flow of urine from the kidney, leading to progressive atrophy of the kidney.-Signs and symptoms:...
- Postrenal azotemia: when kidney stone blocks ureter
- Frequency in micturition: Defined as an increase in number of voids per day (>than 5 times), but not polyuria
In medicine, polyuria is a condition characterized by the passage of large volumes of urine .Polyuria often appears in conjunction with polydipsia , though it is possible to have one without the other, and the latter may be a cause or an effect...
, an increase of total urine output per day (2500 ml).
- Loss of appetite
- Loss of weight
Weight loss, in the context of medicine, health or physical fitness, is a reduction of the total body mass, due to a mean loss of fluid, body fat or adipose tissue and/or lean mass, namely bone mineral deposits, muscle, tendon and other connective tissue...
Diagnosis
Clinical diagnosis is usually made on the basis of the location and severity of the pain, which is typically
colickyRenal colic is a type of pain commonly caused by kidney stones.-Presentation:The pain typically begins in the loin region and often radiates to the hypochondrium or the groin. The pain is often colicky due to ureteric peristalsis, but may be constant...
in nature (comes and goes in spasmodic waves). Pain in the back occurs when calculi produce an obstruction in the kidney.
Imaging is used to confirm the diagnosis and a number of other tests can be undertaken to help establish both the possible cause and consequences of the stone.
X-rays
The relatively dense calcium renders these stones radio-opaque and they can be detected by a traditional
X-rayX-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays...
of the abdomen that includes the Kidneys, Ureters and Bladder—KUB. This may be followed by an
IVPAn intravenous pyelogram is a radiological procedure used to visualize abnormalities of the urinary system, including the kidneys, ureters, and bladder.-Procedure:...
(Intravenous Pyelogram; (IntraVenous Urogram (IVU) is the same test by another name)) which requires about 50 ml of a special dye to be injected into the bloodstream that is excreted by the kidneys and by its density helps outline any stone on a repeated X-ray. These can also be detected by a
Retrograde pyelogramRetrograde Pyelogram is a urologic procedure where the physician injects contrast into the ureter in order to visualize the ureter and kidney. The flow of contrast is opposite the usual flow of urine, hence the retrograde name.Reasons for performing a retrograde pyelogram include identification of...
where similar "dye" is injected directly into the ureteral opening in the bladder by a surgeon, usually a urologist.
About 10% of stones do not
have enough calcium to be seen on standard x-rays (radiolucent stones).
Computed tomography
Computed tomographyComputed tomography is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.CT...
without contrast is considered the gold-standard diagnostic test for the detection of kidney stones. All stones are detectable by CT except very rare stones composed of certain drug residues in the urine. If positive for stones, a single standard x-ray of the abdomen (KUB) is recommended. This gives a clearer idea of the exact size and shape of the stone as well as its surgical orientation. Further, it makes it simple to follow the progress of the stone by doing another x-ray in the future.
Draw back of CT scans include radiation exposure and cost.
Ultrasound
UltrasoundUltrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Although this limit varies from person to person, it is approximately 20 kilohertz in healthy, young adults and thus, 20 kHz serves as a useful lower limit in describing ultrasound...
imaging is useful as it gives details about the presence of
hydronephrosisHydronephrosis is distension and dilation of the renal pelvis and calyces, usually caused by obstruction of the free flow of urine from the kidney, leading to progressive atrophy of the kidney.-Signs and symptoms:...
(swelling of the kidney—suggesting the stone is blocking the outflow of urine). It can also be used to detect stones during pregnancy when x-rays or CT are discouraged. Radiolucent stones may show up on ultrasound however they are also typically seen on
CT scansComputed tomography is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.CT...
.
Some recommend that US be used as the primary diagnostic technique with CT being reserved for those with negative US result and continued suspicion of a kidney stone. This is due to its lesser cost and lack of radiation exposure.
Other
Other investigations typically carried out include:
- Microscopic study of urine, which may show proteins, red blood cells, bacteria, cellular casts and crystals.
- Culture of a urine sample to exclude urine infection (either as a differential
A differential diagnosis is a systematic method used to identify unknowns. This method, essentially a process of elimination, is used by taxonomists to identify living organisms, and by physicians or other clinicians to diagnose the specific disease in a patient.Not all medical diagnoses are...
cause of the patient's pain, or secondary to the presence of a stone)
- Blood tests: Full blood count for the presence of a raised white cell
White blood cells , or leukocytes , are cells of the immune system defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a...
count (NeutrophiliaNeutrophilia is a condition where a person has a high number of neutrophil granulocytes in their blood.-Causes:...
) suggestive of infection, a check of renal functionRenal function, in nephrology, is an indication of the state of the kidney and its role in renal physiology. Glomerular filtration rate describes the flow rate of filtered fluid through the kidney...
and to look for abnormally high blood calcium blood levels (hypercalcaemiaHypercalcaemia is an elevated calcium level in the blood. . It can be an asymptomatic laboratory finding, but because an elevated calcium level is often indicative of other diseases, a diagnosis should be undertaken if it persists...
).
- 24 hour urine collection to measure total daily urinary volume, magnesium, sodium, uric acid, calcium, citrate, oxalate
An oxalate is the deprotonated, charged form of oxalic acid or an ester of oxalic acid. The oxalate anion has the chemical formula C2O42−, also written...
and phosphateA phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...
.
- Catching of passed stones at home (usually by urinating through a tea strainer
A tea strainer is a type of strainer that is placed over or in a teacup to catch tea leaves.When tea is brewed in the traditional manner in a teapot, the tea leaves are not contained in teabags, but rather are freely suspended in the water. As the leaves themselves may be distasteful, it is usual...
or stonescreen) for later examination and evaluation by a doctor.
Temporizing
About 90% of stones 4 mm or less in size usually will pass spontaneously, however 99% of stones larger than 6 mm will require some form of intervention. There are various measures that can be used to encourage the passage of a stone. These can include increased hydration, medication for treating infection and reducing pain, and diuretics to encourage urine flow and prevent further stone formation. Caution should be exercised in eating certain foods, such as
starfruitCarambola or starfruit is the fruit of Averrhoa carambola, a species of tree native to Indonesia, India and Sri Lanka. The tree and its fruit are popular throughout Southeast Asia, Malaysia, the South Pacific and other parts of East Asia...
, with high concentrations of
oxalateAn oxalate is the deprotonated, charged form of oxalic acid or an ester of oxalic acid. The oxalate anion has the chemical formula C2O42−, also written...
which may precipitate acute renal failure in patients with chronic renal disease.
In most cases, a smaller stone that is not symptomatic is often given up to four weeks to move or pass before consideration is given to any surgical intervention as it has been found that waiting longer tends to lead to additional complications. Immediate surgery may be required in certain situations such as in people with only one working kidney, intractable pain or in the presence of an infected kidney blocked by a stone which can rapidly cause severe
sepsisSepsis is a serious medical condition that is characterized by a whole-body inflammatory state and the presence of a known or suspected infection.
and toxic shockSeptic shock is a serious medical condition caused by decreased tissue perfusion and oxygen delivery as a result of infection and sepsis, though the microbe may be systemic or localized to a particular site. It can cause multiple organ dysfunction syndrome and death...
.
Analgesia
Management of pain from kidney stones varies from country to country and even from physician to physician, but usually requires intravenous administration of opioids in an emergency room setting for acute situations. Similarly, drugs may be reasonably effective orally in an outpatient setting for less severe discomfort where nonsteroidal anti-inflammatories or opioids such as codeine or hydrocodoneHydrocodone or dihydrocodeinone is a semi-synthetic opioid derived from two of the naturally occurring opiates codeine and thebaine. Hydrocodone is an orally active narcotic analgesic and antitussive. It is commonly available in tablet, capsule, and syrup form, and is often compounded with other...
can be prescribed. Some doctors will give patients with recurring passing of small stones a small supply prescription for hydrocodone to avoid a future visit to the ER when the next episode occurs. Taken at the first sign of pain, hydrocodone can eliminate much of the acute pain, nausea and vomiting which necessitates the hospital visit and still facilitate stone passage, although a follow-up with a physician is still necessary.
Patients who are to be treated non-surgically, may also be started on an alpha adrenergic blocking agent (such as Flomax, Uroxatral, terazosinTerazosin is a selective alpha 1 antagonist used for treatment of symptoms of an enlarged prostate . It also acts to lower the blood pressure, and is therefore a drug of choice for men with hypertension and prostate enlargement....
or doxazosinDoxazosin mesylate, a quinazoline compound sold by Pfizer under the brand names Cardura and Carduran, is an alpha blocker used to treat high blood pressure and benign prostatic hyperplasia....
), which acts to reduce the muscle tone of the ureter and facilitate stone passage. For smaller stones near the bladder, this type of medical treatment can increase the spontaneous stone passage rate by about 30%.
After treatment, the pain may return if the stone moves but re-obstructs in another location. Patients are encouraged to strain their urine so they can collect the stone when it eventually passes and send it for chemical composition analysis which will be used along with a 24 hour urine chemical analysis test to establish preventative options.
Urologic interventions
Most kidney stones do not require surgery and will pass on their own. Surgery is necessary when the pain is persistent and severe, in renal failure and when there is a kidney infection. It may also be advisable if the stone fails to pass or move after 30 days. Finding a significant stone before it passes into the ureter allows physicians to fragment it surgically before it causes any severe problems. In most of these cases, non-invasive extracorporeal shock wave lithotripsy (ESWL) will be used. Otherwise some form of invasive procedure is required; with approaches including ureteroscopic fragmentation (or simple basket extraction if feasible) using laserA laser is a device that emits light through a process called stimulated emission. Laser light is usually spatially coherent, which means that the light either is emitted in a narrow, low-divergence beam, or can be converted into one with the help of optical components such as lenses...
, ultrasonic or mechanical (pneumatic, shock-wave) forms of energy to fragment the larger stones. PercutaneousIn surgery, percutaneous pertains to any medical procedure where access to inner organs or other tissue is done via needle-puncture of the skin, rather than by using an "open" approach where inner organs or tissue are exposed .The percutaneous approach is commonly used in vascular procedures...
nephrolithotomyLithotomy from Greek for "lithos" and "tomos" , is a surgical method for removal of calculi, stones formed inside certain hollow organs, such as the bladder and kidneys and gallbladder , that cannot exit naturally through the urethra, ureter or biliary duct...
or rarely open surgerySurgery is a medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance, or sometimes for some other reason...
may ultimately be necessary for large or complicated stones or stones which fail other less invasive attempts at treatment.
A single retrospective study in the USAThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, at the Mayo ClinicMayo Clinic is a non-profit organization and internationally renowned group medical practice headquartered in Rochester, Minnesota. Its headquarters consist of the Mayo Medical School, the Mayo Graduate School, the Mayo College of Graduate Medical Education, and several other health science schools...
, has suggested that lithotripsy may increase subsequent incidence of diabetes and hypertension,
but it has not been felt warranted to change clinical practice at the clinic. The study reflects early experience with the original lithotripsy machine which had a very large blast path, much larger than what is used on modern machines. Further study is believed necessary to determine how much risk this treatment actually has using modern machines and treatment regimens.
More common complications related to ESWL are bleeding, pain related to passage of stone fragments, failure to fragment the stone, and the possible requirement for additional or alternative interventions ~.
Ureteral (double-J) stents
One modern medical technique uses a ureteral stentA ureteral stent, sometimes as well called ureteric stent, is a thin tube inserted into the ureter to prevent or treat obstruction of the urine flow from the kidney. The length of the stents used in adult patients varies between 24 to 30 cm. Additionally, stents come in differing diameters or...
(a small tube between the bladder and the inside of the kidney) to provide immediate relief of a blocked kidney. This is especially useful in saving a failing kidney due to swelling and infection from the stone. Ureteral stents vary in length and width but most have the same shape usually called a "double-J" or "double pigtail", because of the curl at both ends. They are designed to allow urine to drain around any stone or obstruction. They can be retained for some length of time as infections recede and as stones are dissolved or fragmented with ESWL or other treatment. The stents will gently dilate or stretch the ureters which can facilitate instrumentation and they will also provide a clear landmark to help surgeons see the stones on x-ray. Most stents can be removed easily during a final office visit. Discomfort levels from stents typically range from minimal associated pain to moderate discomfort. However, it isn't uncommon for patients to experience severe discomfort too, especially upon removal of said stent.
Prevention
Preventive strategies include dietary modifications and sometimes also taking drugs with the goal of reducing excretory load on the kidneys:
- Drinking enough water to make 2 to 2.5 liter
s of urine per day.
- A diet low in protein
Proteins are organic compounds made of amino acids arranged in a linear chain and folded into a globular form. The amino acids in a polymer chain are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues...
, nitrogenNitrogen is a chemical element that has the symbol N and atomic number 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless and mostly inert diatomic gas at standard conditions, constituting 78% by volume of Earth's atmosphere.Many industrially important...
and sodiumSodium is a metallic element with a symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals within "group 1"...
intake.
- Restriction of oxalate
An oxalate is the deprotonated, charged form of oxalic acid or an ester of oxalic acid. The oxalate anion has the chemical formula C2O42−, also written...
-rich foods, such as chocolateChocolate comprises a number of raw and processed foods produced from the seed of the tropical cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America, with its earliest documented use around 1100 BC...
, nuts, soybeanThe soybean or soya bean is a species of legume native to East Asia. The plant is classed as an oilseed rather than a pulse. It is an annual plant that has been used in China for 5,000 years to primarily add nitrogen into the soil as part of crop rotation...
s, rhubarbRhubarb is a group of plants that belong to the genus Rheum in the family Polygonaceae. They are herbaceous perennial plants growing from short, thick rhizomes. They have large leaves that are somewhat triangular shaped with long fleshy petioles. They have small flowers grouped in large compound...
and spinachSpinach is an edible flowering plant in the family of Amaranthaceae. It is native to central and southwestern Asia. It is an annual plant , which grows to a height of up to 30 cm. Spinach may survive over winter in temperate regions...
, plus maintenance of an adequate intake of dietary calcium. There is equivocal evidence that calcium supplements increase the risk of stone formation, though calcium citrate appears to carry the lowest, if any, risk.
- Taking drugs such as thiazides, potassium citrate
Potassium citrate may be used to control kidney stones due to either uric acid or cystine.Chemical Formula: C
6H
5K
3O
7 + H
2O...
, magnesium citrateMagnesium citrate is a chemical agent used medicinally as a saline laxative and to empty the bowel prior to a surgery or colonoscopy. It is available without a prescription, both as a generic brand or under the brand name Citromag or Citroma. It is also used as a magnesium supplement in pills...
and allopurinolAllopurinol is a drug used primarily to treat hyperuricemia and its complications, including chronic gout.- Mechanism of action :...
, depending on the cause of stone formation.
- Some fruit juices, such as orange, blackcurrant, and cranberry, may be useful for lowering the risk factors for specific types of stones. Orange juice may help prevent calcium oxalate stone formation, black currant may help prevent uric acid stones, and cranberry may help with UTI-caused stones.
- Avoidance of cola
Cola is a beverage usually containing caramel coloring, caffeine, and a sweetener such as sugar or high fructose corn syrup.Originally invented by the druggist John Pemberton, it has become popular worldwide. Coca-Cola has become the major international brand, leading to the drink often being seen...
beverages.
- Avoiding large doses of vitamin C
Vitamin C or L-ascorbic acid is an essential nutrient for humans, in which it functions as a vitamin. Ascorbate is required for a range of essential metabolic reactions in all animals and plants...
.
For those patients interested in optimizing their kidney stone prevention options, a 24 hour urine test can be a useful diagnostic.
Restricting oxalate consumption
Calcium plays a vital role in body chemistry so limiting calcium may be unhealthy. Since calcium in the intestinal tract will bind with available oxalate, thereby preventing its absorption into the blood stream, some nephrologists and urologists recommend chewing calcium tablets during meals containing oxalate foods. However, a more reliable approach is to restrict the intake of food that is high in oxalate (see oxalic acidOxalic acid is the chemical compound with the formula C2O22 or HOOCCOOH. This colourless solid is a relatively strong carboxylic acid, being about 3,000 times stronger than acetic acid. The dianion, known as oxalate, is a reducing agent as well as a ligand for...
for a list). This is only helpful in those patients who are absorbing excess oxalate which is a minority of patients as most oxalate excreted in the urine is actually made by the liver.
Diuretics
Although it has been claimed that the diureticA diuretic is any drug that elevates the rate of urination and thus provides a means of forced diuresis. There are several categories of diuretics...
effects of alcohol can result in dehydrationDehydration is defined as excessive loss of body water. It is literally the removal of water from an object. In physiological terms, it entails a relative deficiency of water molecules in relation to other dissolved solutes...
, which is important for kidney stone sufferers to avoid, there are no conclusive data demonstrating any cause and effect regarding kidney stones. However, some have theorized that frequent and binge drinkers create situations that set up dehydration: alcohol consumption, hangovers, and poor sleep and stress habits. In this view, it is not the alcohol that creates a kidney stone but it is the alcohol drinker's associated behavior that sets it up.
One of the recognized medical therapies for prevention of stones is thiazideThiazide is a term used to describe a type of molecule and a class of diuretics often used to treat hypertension and edema ....
s, a class of drugs usually thought of as diuretics. These drugs prevent calcium stones through an effect independent of their diuretic properties: they reduce urinary calcium excretion. Nonetheless, their diuretic property does not preclude their efficacy as stone preventive. Sodium restriction is necessary for clinical effect of thiazides, as sodium excess promotes calcium excretion. Thiazides work best for renal leak hypercalciuria - a condition in which the high urinary calcium levels are from a primary kidney defect. They work well initially for absorptive hypercalciuria - a condition in which high urinary calcium is a result of excess absorption from the GI tract. With this condition they lose effectiveness over time, typically around 2 years, and patients need a period off treatment to regain effectiveness. Thiazides will cause hypokalemiaHypokalemia Hypokalaemia refers to the condition in which the concentration of potassium in the blood is low. The prefix hypo- means low...
and reduced urinary citrate levels so should be given with supplements for each, usually as a potassium citrate preparation.
Allopurinol
AllopurinolAllopurinol is a drug used primarily to treat hyperuricemia and its complications, including chronic gout.- Mechanism of action :...
(Zyloprim) is another drug with proven benefits in some calcium kidney stone formers. Allopurinol interferes with the liver's production of uric acidUric acid is an organic compound of carbon, nitrogen, oxygen and hydrogen with the formula C
5H
4N
4O
3.-Biology:...
. HyperuricosuriaHyperuricosuria is a medical term referring to the presence of excessive amounts of uric acid in the urine. Notable direct causes of hyperuricosuria are dissolution of uric acid crystals in the kidneys or urinary bladder, and hyperuricemia...
, too much uric acid in the urine, is a risk factor for calcium stones. Allopurinol reduces calcium stone formation in such patients. The drug is also used in patients with goutGout is a disease hallmarked by elevated levels of uric acid in the bloodstream. In this condition, crystals of monosodium urate or uric acid are deposited on the articular cartilage of joints, tendons, and surrounding tissues...
or hyperuricemiaHyperuricemia is a level of uric acid in the blood that is abnormally high. In humans, the upper end of the normal range is 360 µmol/L for women and 400 µmol/L for men.-Causes:...
. However, hyperuricemia is not the critical feature of uric acid stones, which can occur in the presence of hypouricemiaHypouricemia is a level of uric acid in blood serum that is below normal. In humans, the normal range of this blood component has a lower threshold set variously in the range of 2 mg/dL to 4 mg/dL, while the upper threshold is 530 micromol/L for women and 619 micromol/L for men...
. Uric acid stones are more often caused by a combination of high urine uric acid and low urine pHpH is a measure of the acidity or basicity of a solution. It is defined as the cologarithm of the activity of dissolved hydrogen ions . Hydrogen ion activity coefficients cannot be measured experimentally, so they are based on theoretical calculations...
. Even relatively high uric acid excretion will not be associated with uric acid stone formation if the urine pH is alkaline. Therefore prevention of uric acid stones relies on alkalinization of the urine with citrateA citrate can refer either to the conjugate base of citric acid, , or to the esters of citric acid...
(in the form of Shohl's solution (sodium citrate), sodium bicarbonateSodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slight alkaline taste resembling that of washing soda . It is a component of the...
, potassium citrate, potassium bicarbonate or acetazolamideAcetazolamide, sold under the trade name Diamox, is a carbonic anhydrase inhibitor that is used to treat glaucoma, epileptic seizures, benign intracranial hypertension , altitude sickness, cystinuria, and dural ectasia...
, a carbonic anhydrase inhibitor).
Allopurinol is reserved for patients in whom alkalinization is difficult. For patients with increased uric acid levels and calcium stones, allopurinol is one of the few treatments that has been shown in double-blinded placebo controlled studies to actually reduce kidney stone recurrences. Dosage is adjusted to maintain a reduced urinary excretion of uric acid. Serum uric acid level at or below 6 mg/dLA gram per litre or liter is a measurement of concentration used to measure the how many grams of a certain substance are present in one litre of liquid.It is not an SI unit because it contains the non-SI unit "litre"...
is often the goal of the drug's use in patients with gout or hyperuricemia.
Decreased protein diet
A high protein dietA high protein diet is often recommended by bodybuilders and nutritionists to help efforts to build muscle and lose fat. It should not be confused with low-carb diets such as the Atkins Diet, which are not calorie-controlled and which often contain large amounts of fat.While adequate protein is...
might be partially to blame. Protein from meat and other animal products is broken down into acids, including uric acid. The most available alkaline baseIn chemistry, a base is most commonly thought of as an aqueous substance that can accept hydrogen ions. Bases are also the oxides or hydroxides of metals. A soluble base is also often referred to as an alkali if hydroxide ions are involved. This refers to the Brønsted-Lowry theory of acids and bases...
to balance the acid from protein is calciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust...
phosphate (hydroxyapatite) from the bones (buffering). The kidney filters the liberated calcium which may then form insoluble crystals (i.e., stones) in urine with available oxalate (partly from metabolic processes, partly from diet) or phosphate ions, depending on conditions. High protein intake is therefore associated with decreased bone density as well as stones. The acid load is associated with decreased urinary citrate excretion; citrate competes with oxalate for calcium and can thereby prevent stones.
In addition to increased fluid intake, one of the simplest fixes is to moderate animal protein consumption. However, despite epidemiologic data showing that greater protein intake is associated with more stones, randomized controlled trials of protein restriction have not shown reduced stone prevalence. In this regard, it is not just dietary calcium per se that may cause stone formation, but rather the leaching of bone calcium. Some diseases (e.g., distal renal tubular acidosisRenal tubular acidosis is a medical condition that involves an accumulation of acid in the body due to a failure of the kidneys to appropriately acidify the urine. When blood is filtered by the kidney, the filtrate passes through the tubules of the nephron, allowing for exchange of salts, acid...
) which cause a chronically acidic state also decrease urinary citrate levels; since citrates are normally present as potent inhibitors of stone formation, these patients are prone to frequent stone formation.
Other modifications
Potassium citratePotassium citrate may be used to control kidney stones due to either uric acid or cystine.Chemical Formula: C
6H
5K
3O
7 + H
2O...
is also used in kidney stone prevention. This is available as both a tablet and liquid preparation. The medication increases urinary pH (makes it more alkaline), as well as increases the urinary citrate level, which helps reduce calcium oxalate crystal aggregation. Optimal 24 hour urine levels of citrate are thought to be over 320 mg/liter of urine or over 600 mg per day. There are urinary dipsticks available that allow patients to monitor and measure urinary pH so patients can optimize their urinary citrate level.
Though caffeineCaffeine is a bitter, white crystalline xanthine alkaloid that is a psychoactive stimulant drug. Caffeine was discovered by a German chemist, Friedrich Ferdinand Runge, in 1819. He coined the term kaffein, a chemical compound in coffee, which in English became caffeine...
does acutely increase urinary calcium excretion, several independent epidemiologic studies have shown that coffee intake overall is protective against the formation of stones.
Measurements of food oxalate content have been difficult and issues remain about the proportion of oxalate that is bio-available, versus a proportion that is not absorbed by the intestine. Oxalate-rich foods are usually restricted to some degree, particularly in patients with high urinary oxalate levels, but no randomized controlled trial of oxalate restriction has been performed to test that hypotheses.
Calgranulin
CrystallizationCrystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas...
of calcium oxalate (CaOx) appears to be reduced by molecules in the urineUrine is a liquid waste product of the body secreted by the kidneys by a process of filtration from blood called urination and excreted through the urethra. Cellular metabolism generates numerous waste compounds, many rich in nitrogen, that require elimination from the bloodstream...
that retard the formation, growth, aggregation, and renal cell adherence of calcium oxalate. By purifying urine using salt precipitation, preparative isoelectric focusing, and sizing chromatography, some researchers have found that the molecule calgranulin is able to inhibit calcium oxalate crystal growth. Calgranulin is a protein formed in the kidney. Given the large amounts of calcium oxalate in the urine, and considering its potency, calgranulinCalgranulin is an S-100 calcium-binding protein that is expressed in multiple cell types, including renal epithelial cells and neutrophils. Some in vitro evidence suggests that calgranulin can inhibit the precipitation of calcium oxalate in a urine-like environment at calgranulin concentrations...
could become an important contribution to the normal urinary inhibition of crystal growth and aggregation. If so, it will be an important tool in the renal defense against kidney stones.
Epidemiology
Within the United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, about 10–15% of adults will be diagnosed with a kidney stone, and the total cost for treating this condition was US$The United States dollar is the unit of currency of the United States. The U.S. dollar is normally abbreviated as the dollar sign, $, or as USD or US$ to distinguish it from other dollar-denominated currencies and from others that use the $ symbol. It is divided into 100 cents .The U.S...
2 billion in 2003. The incidence rate increases to 20–25% in the Middle EastThe Middle East is a region that spans southwestern Asia, southeastern Europe, and northeastern Africa. It has no clear boundaries, often used as a synonym to Near East, in opposition to Far East...
, because of increased risk of dehydration in hot climates. (The typical Arabian diet is also 50% lower in calciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust...
and 250% higher in oxalateAn oxalate is the deprotonated, charged form of oxalic acid or an ester of oxalic acid. The oxalate anion has the chemical formula C2O42−, also written...
s compared to Western diets, increasing the net risk.) Recurrence rates are estimated at about 10% per year, totalling 50% over a 5–10 year period and 75% over 20 years. Men are affected approximately 4 times more often than women. Recent evidence has shown an increase in pediatric cases.
History
The existence of kidney stones has been recorded since the beginning of civilization, and lithotomyLithotomy from Greek for "lithos" and "tomos" , is a surgical method for removal of calculi, stones formed inside certain hollow organs, such as the bladder and kidneys and gallbladder , that cannot exit naturally through the urethra, ureter or biliary duct...
for the removal of stones is one of the earliest known surgical procedures. In 1901, a stone was discovered in the pelvis of an ancient Egyptian mummyA mummy is a corpse whose skin and organs have been preserved by either intentional or incidental exposure to chemicals, extreme coldness, very low humidity, or lack of air when bodies are submerged in bogs...
, and was dated to 4,800 BC. Medical
text from ancient MesopotamiaMesopotamia "land between the rivers" is a name for the Tigris–Euphrates region in the eastern Mediterranean, largely corresponding to Iraq, as well as northeastern Syria, some parts of southeastern Turkey, and some parts of the Khūzestān Province of southwestern...
, IndiaAncient India may refer to:*The ancient History of India, which generally includes the ancient history of the whole Indian subcontinent **Indus Valley Civilization — during the Bronze Age...
, ChinaChinese civilization originated in various city-states along the Yellow River valley in the Neolithic era. The written history of China begins with the Shang Dynasty . Turtle shells with ancient Chinese writing from the Shang Dynasty have been carbon dated to as early as 1500 BCE...
, Persia, GreeceAncient Greece is the civilisation belonging to the period of Greek history lasting from the Greek Dark Ages ca. 1100 BC and the Dorian invasion, to 146 BC and the Roman conquest of Greece after the Battle of Corinth. It is generally considered to be the seminal culture which provided the...
and RomeAncient Rome was a civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC. Located along the Mediterranean Sea, it became one of the largest empires in the ancient world....
all mentioned calculous disease. Part of the Hippocratic oathThe Hippocratic Oath is an oath traditionally taken by doctors swearing to ethically practice medicine. It is widely believed to have been written by Hippocrates, the father of western medicine, in Ionic Greek , or by one of his students, and is usually included in the Hippocratic Corpus...
contains an admonition about the dangers of operating on the bladder for stones. The Roman medical treatise De MedicinaDe Medicina is a 1st-century medical treatise by Aulus Cornelius Celsus, a Roman encyclopedist and possibly a practicing physician. It is the only surviving section of a much larger encyclopedia; only small parts still survive from sections on agriculture, military science, oratory, jurisprudence...
by Cornelius Celsus contained a description of lithotomy, and this work served as the basis for this procedure up until the 18th century.
New techniques in lithotomy began to emerge starting in 1520, but the operation remained risky. It was only after Henry Jacob BigelowHenry Jacob Bigelow was an American surgeon and Professor of Surgery at Harvard University. He was a vocal opponent of vivisection and was best known for his description of the hip joint and for a technique for treating patients with kidney stones.-Biography:Bigelow was born on March 11, 1818 in...
popularized the technique of litholopaxy in 1878 that the mortality rate dropped from about 24% down to 2.4%. However, other treatment techniques were developed that continued to produce a high level of mortality, especially among inexperienced urologists. In 1980, Dornier MedTech introduced extracorporeal shock wave lithotripsyExtracorporeal Shock Wave Lithotripsy is the non-invasive treatment of kidney stones and biliary calculi...
for breaking up stones via acoustical pulses, and this technique has come into widespread use.
See also
- Nephrology
Nephrology is a branch of internal medicine and pediatrics dealing with the study of the function and diseases of the kidney.- Scope of the specialty :...
- Urinary retention
Urinary retention also known as ischuria is a lack of ability to urinate. It is a common complication of benign prostatic hypertrophy , although anticholinergics may also play a role, and requires a catheter or prostatic stent...
- Urology
Urology is the surgical specialty that focuses on the urinary tracts of males and females, and on the reproductive system of males. Medical professionals specializing in the field of urology are called urologists and are trained to diagnose, treat, and manage patients with urological disorders...
- Retrograde pyelogram
Retrograde Pyelogram is a urologic procedure where the physician injects contrast into the ureter in order to visualize the ureter and kidney. The flow of contrast is opposite the usual flow of urine, hence the retrograde name.Reasons for performing a retrograde pyelogram include identification of...
- Cystinuria
Cystinuria is an inherited autosomal recessive metabolic disorder that is characterized by the formation of cystine stones in the kidneys, ureter, and bladder.-Signs and symptoms:In acidic pH, cystine crystals are formed in the urine....
- Intravenous pyelogram
An intravenous pyelogram is a radiological procedure used to visualize abnormalities of the urinary system, including the kidneys, ureters, and bladder.-Procedure:...
- Kidney stone sufferers
External links