A kidney stone is a hard, crystalline mineral material formed within the kidney or urinary tract. Kidney stones are a common cause of blood in the urine (haematuria) and often severe pain in the abdomen, flank, or groin. Kidney stones are sometimes called renal calculi. One in every 20 people develops kidney stones at some point in their life.
Kidney stones form when there is a decrease in urine volume and/or an excess of stone-forming substances in the urine.
The condition of having kidney stones is termed nephrolithiasis. Having stones at any location in the urinary tract is referred to as urolithiasis, and the term ureterolithiasis is used to refer to stones located in the ureters.
Signs & symptoms
Some kidney stones may not produce symptoms (known as “silent” stones)
Acute excruciating & cramping pain in their low back and/or side, groin, or abdomen which does not resolve by change in body position.
The abdominal, groin, and/or backpain mimics colicky pain (the pain is referred to as renal colic).
Nausea and vomiting.
Haematuria (Blood in urine).
Fever and chills if infection is present.
Urgency of urine
Pain in the penis or vulva
- Dehydration is a major risk factor for kidney stone formation.
- hereditary factors
Kidney stones form when there is a decrease in urine volume and/or an excess of stone-forming substances in the urine. The most common type of kidney stone contains calcium in combination with either oxalate or phosphate. A majority of kidney stones are calcium stones. Other chemical compounds that can form stones in the urinary tract include uric acid, magnesium ammonium phosphate (which forms struvite stones; see below), and the amino acid cysteine.
Dehydration from reduced fluid intake or strenuous exercise without adequate fluid replacement increases the risk of kidney stones. Obstruction to the flow of urine can also lead to stone formation. In this regard, climate may be a risk factor for kidney stone development, since residents of hot and dry areas are more likely to become dehydrated and susceptible to stone formation.
Kidney stones can also result from infection in the urinary tract. These are known as struvite or infection stones. Metabolic abnormalities, including inherited disorders of metabolism, can alter the composition of the urine and increase an individual’s risk of stone formation.
- Gout results in chronically increased amount of uric acid in the blood and urine and can lead to the formation of uric acid kidney stones.
- Hypercalciuria (high calcium in the urine), another inherited condition, causes stones in more than half of cases. In this condition, too much calcium is absorbed from food and excreted into the urine, where it may form calcium phosphate or calcium oxalate kidney stones.
- Other conditions associated with an increased risk of kidney stones include hyperparathyroidism, kidney diseases such as renal tubular acidosis, and other inherited metabolic conditions, including cystinuria and hyperoxaluria.
- Chronic diseases such as diabetes and high blood pressure.
- Inflammatory bowel disease
- After intestinal bypass or ostomy surgery
- Some medications also raise the risk of kidney stones. These medications include some diuretics, calcium-containing antacids, and medicines used in a HIV infection.
- Dietary factors and practices may increase the risk of stone formation in susceptible individuals. In particular, inadequate fluid intake predisposes to dehydration, which is a major risk factor for stone formation. Other dietary practices that may increase an individual’s risk of forming kidney stones include a high intake of animal protein, a high-salt diet, excessive sugar consumption, excessive vitamin D supplementation, and excessive intake of oxalate-containing foods such as spinach. Interestingly, low levels of dietary calcium intake may alter the calcium-oxalate balance and result in the increased excretion of oxalate and a propensity to form oxalate stones.
- Hyperoxaluria as an inherited condition is uncommon and is known as primary hyperoxaluria. The elevated levels of oxalate in the urine increase the risk of stone formation. Primary hyperoxaluria is much less common than hyperoxaluria due to dietary factors as mentioned above.
As a stone moves from the renal collecting system, it can significantly affect the genitourinary tract. It can cause constant or intermittent obstruction and hydronephrosis of the ureter, causing urine to back up into the kidney. Intermittent obstruction often causes longer-lasting discomfort and pain than a constant blockage where compensatory mechanisms can offset the increased ureteral intraluminal pressure to some degree. An acute ureteral obstruction causes a decrease in the glomerular filtration rate of the affected kidney and increases urine excretion by the unaffected renal unit as well as very severe, excruciating pain. Complete obstruction of the ureter can lead to the eventual loss of renal function, with damage becoming irreversible, possibly starting at just one to two weeks. Additionally, there is a risk of rupture of a renal calyx with the development of a urinoma. Of even more concern is the possibility that an obstructed renal unit might become infected, causing obstructive pyelonephritis or pyonephrosis. This condition can be life-threatening and requires immediate surgical drainage as antibiotics alone will be ineffective.
Renal calculi can become impacted, most commonly at one of three locations: 1) at the ureteropelvic junction, as the renal pelvis narrows abruptly to meet the ureter, 2) near the pelvic brim, where the ureter takes a posterior turn, or 3) at the ureterovesical junction which is the narrowest portion of the ureter.
Pain is the result of a combination of ureteral muscle spasms, increased proximal peristalsis from activation of intrinsic ureteral pacemakers, stone-induced localized inflammatory changes, renal swelling with capsular stretching, oedema, and irritation. These processes stimulate submucosal stretch receptors in the ureter, renal pelvis, and capsule which are a direct cause of pain. Of all the various factors that can contribute to flank pain and renal colic, stimulation of the renal pelvis, peri pelvic renal capsule, and calices from stretching most closely mimics typical renal colic.
The immediate effect of a newly obstructing ureteral stone is to increase proximal intraluminal pressure which initially distends the renal pelvis and increases ureteral peristalsis. Peak renal pelvic pressure from a high-grade obstruction is usually obtained within two to five hours of a complete ureteric obstruction. Other changes in the kidneys after a complete ureteral blockage include pyelolymphatic and pyelovenous backflow. Interstitial renal edema develops which significantly increases lymphatic drainage from the affected kidney and stretches the renal capsule leading directly to painful stimuli from capsular stretch receptors.
Often, a state of equilibrium will be achieved as the increasing proximal ureteral dilation allows some urine to pass around the obstruction which is enough, along with the other compensatory measures, to relieve the pain and achieve stability.
Pain fibers are primarily through the preganglionic sympathetic nerves and the ascending spinothalamic tracts. When the stone approaches the intramural ureter, the nervi erigentes can become involved which can cause various bladder symptoms including frequency, urgency, dysuria, hesitancy and difficulty in voiding.
Renal blood flow increases for the first 90 minutes after initial ureteral blockage before diminishing. This is caused by vasodilation of the afferent preglomerular arterial blood supply. By five hours after the ureteral obstruction, renal blood flow and ureteral intraluminal pressures have decreased back to normal or below. Over time, renal blood flow tends to slowly diminish. After three days, renal blood flow has dropped to about half from the normal baseline and this continues to slowly diminish over time. By eight weeks, renal blood flow is only 12% of its prior, normal baseline value. Even then, the dilation and hydroureteronephrosis usually remains but ureteral peristalsis has almost disappeared. Renal blood flow in the contralateral kidney has increased at this point.
Nausea and vomiting are associated with classic renal colic in about half or more of patients with acute obstructing calculi. This is due to a common innervation pathway between the kidneys and the GI tract embryologically through afferents of the Vagus nerve and celiac axis. This effect can be exacerbated by NSAIDs and opioid medications that have GI side effects.
- Diagnosis of kidney stones is best accomplished using an ultrasound, intravenous pyelography (IVP), or a CT scan.
- The diagnosis of kidney stones is suspected when the typical pattern of symptoms is noted and when other possible causes of the abdominal or flank pain are excluded. Which is the ideal test to diagnose kidney stones is controversial. Imaging tests are usually done to confirm the diagnosis. Many patients who go to the emergency room will have a non-contrast CT scan done. This can be done rapidly and will help rule out other causes for flank or abdominal pain. However, a CT scan exposes patients to significant radiation, and recently, ultrasound in combination with plain abdominal X-rays have been shown to be effective in diagnosing kidney stones.
- In pregnant women or those who should avoid radiation exposure, an ultrasound examination may be done to help establish the diagnosis.
Most kidney stones will pass through the ureter to the bladder on their own with time. Treatment includes pain-control medications and, in some cases, medications to facilitate the passage of urine. If needed, lithotripsy or surgical techniques may be used for stones which do not pass through the ureter to the bladder on their own.The consumption of ample fluids helps facilitate the passage of kidney stones, but even with plentiful fluid intake, most people require some type of medications for pain control.
Most kidney stones eventually pass through the urinary tract on their own within 48 hours, with ample fluid intake. Ketorolac (Toradol), an injectable anti-inflammatory drug, and narcotics may be used for pain control when over the counter pain control medications are not effective. Toradol, aspirin, and NSAID s must be avoided if lithotripsy is to be done because of the increased risk of bleeding or if there is impaired kidney function. Intravenous pain medications can be given when nausea and vomiting are present.
Although there are no proven home remedies to dissolve kidney stones, home treatment may be considered for patients who have a known history of kidney stones. Since most kidney stones, given time, will pass through the ureter to the bladder on their own, treatment is directed toward control of symptoms. Home care in this case includes the consumption of plenty of fluids. Acetaminophen (Tylenol) may be used as pain medication if there is no contraindication to its use. If further pain medication is needed, stronger narcotic pain medications are recommended.
There are several factors that influence the ability to pass a stone. These include the size of the person, prior stone passage, prostate enlargement, pregnancy, and the size of the stone. A 4 mm stone has an 80% chance of passage while a 5 mm stone has a 20% chance. Stones larger than 9 mm to 10 mm rarely pass without specific treatment.
Some medications have been used to increase the passage rates of kidney stones. These include Calcium channel blockers and alpha blockers.
For kidney stones that do not pass on their own, a procedure called lithotripsy is often used. In this procedure, shock waves are used to break up a large stone into smaller pieces that can then pass through the urinary system.
Surgical techniques have also been developed to remove kidney stones when other treatment methods are not effective. This may be done through a small incision in the skin (percutaneous nephrolithotomy) or through an instrument known as an ureteroscope passed through the urethra and bladder up into the ureter.
Most kidney stones will pass on their own, and successful treatments have been developed to remove larger stones or stones that do not pass. People who have had a kidney stone remain at risk for future stones throughout their lives.
- Abscess formation
- Serious infection of the kidney that diminishes renal function
- Urinary fistula formation
- Ureteral scarring and stenosis
- Ureteral perforation
- Renal loss due to long-standing obstruction
- Complete ureteral obstruction
Infected hydronephrosis is the deadliest complication with chance of rapidly progressive sepsis and death.
A ureteral stone associated with obstruction and upper UTI is a true urologic emergency.
Disease & Ayurveda
Kidney stones – Asmari/ Mootraghata
Diet and behaviour causing Vaata vitiation
Dhmana – Distended bladder
Tadaasannadeseshu parita: atiruk -Unbearable pain near the area of kidney, urinary bladder and ureter
Mootre: bastagandhatwam – Smell of goat in urine
Mootrakrichram – Obstructed and painful urination
Jwara – Fever
Aruchi – Tastelessness
Due to the causative factors, Vitiated vaata gets obstructed in the path of urine and the normal expulsion of urine is affected. The waste materials accumulated forms a stone/calculus gradually and when it causes partial/complete obstruction to the urinary flow, it causes severe pain and other symptoms.
Nabhieevanivastimoordhasu ruk – Pain in navel area, pubis area, and in the area of lower abdomen.
Viseernadharam mootram – Incontinuous flow of urine
Gomedakopamam mootram – Urine resembling gomedaka in colour (Yellow)
(Urine flow happens when the stone moves in the tract causing obstruction)
Kshate saasram aayasath atiruk meheth – If wounded by the stone, it causes pain, bleeding and difficulty while urinating.
Suklaja(Affects only adults, not children)
Commonly used medicines
For some people who have had many kidney stones, home care may be appropriate. When passing a kidney stone, drinking lots of fluid is important. In fact, this is the most important home care measure. Medications may help control the pain temporarily.
- To be avoided
Hot, spicy and pungent food items
Pickles, processed and tinned masala items.
Heavy meals and difficult to digest foods – cause indigestion.
Junk foods- cause disturbance in digestion and reduces the bioavailability of the medicine
Carbonated drinks – makes the stomach more acidic and disturbed digestion
Refrigerated and frozen foods – causes weak and sluggish digestion by weakening Agni (digestive fire)
Curd – causes vidaaha and thereby many other diseases
- To be added
Light meals and easily digestible foods
Green gram, soups, fresh juices, Indian sarsaparilla, tender coconut water, sugar cane, and arrowroot.
Freshly cooked and warm food processed with coriander seeds, cumin seeds, ginger, ajwain etc
Drink enough water and void urine frequently.
Maintain personal hygiene, especially private parts. Avoid using public toilets, using wet undergarments etc.
Protect yourself from dehydration and exposure to heat.
Better to avoid exposure to excessive sunlight, wind, rain or dust.
Maintain a regular food and sleep schedule.
Avoid holding or forcing the urges like urine, faeces, cough, sneeze etc.
In persons with fever, severe pain and severe urinary tract infections, physical exercises are not recommended.
Regular exercise after regaining normal health helps improve bioavailability of the food ingested and leads to positive health.
All the exercises and physical exertions must be decided and done under the supervision of a medical expert only.