Kidney Stones (calculi) are hard masses that form in the urinary tract and may cause pain, bleeding, or an illness or block of the flow of pee.
Tiny stones may cause no symptoms, but larger rocks can cause excruciating pain in the region between the ribs and hips in the back. Ordinarily, an evaluation of urine and an imaging evaluation are done to diagnose stones.
Sometimes kidney stone formation can be prevented by altering the diet or increasing fluid intake.
Stones that do not pass on their own are removed with an endoscopic technique or lithotripsy.
Depending on where a rock is found, it may be called bladder stone, ureteral stone, or a kidney stone. The process of stone formation is called nephrolithiasis, renal lithiasis, or urolithiasis.
Annually, about 1 of 1,000 adults in the United States is hospitalized because of stones in the urinary tract. Rocks are more common among middle-aged and elderly adults and men. A large, so called staghorn (because of its many projections that resemble a deer's antlers), stone may fill nearly the entire renal pelvis (the central collecting chamber of the kidney) and the tubes that drain into it (calices).
Kinds of stones
Stones are made of minerals in the urine that form crystals. Occasionally the crystals grow into stones. About 85% of the rocks are composed of calcium, and the rest are composed of various substances, including cystine, uric acid, or struvite. Struvite stones—a mixture of phosphate, and magnesium, ammonium are also called infection stones, because they form just in infected urine.
Rocks may form because the pee lacks the normal inhibitors of stone formation or because the urine becomes overly saturated with salts that can form rocks. Because it usually binds with calcium which is regularly included in forming rocks citrate is such an inhibitor.
Stones are more common among individuals with certain disorders (for example, hyperparathyroidism, dehydration, and renal tubular acidosis) and among people whose diet is very high in animal-source protein or vitamin C or who tend not to have enough water or calcium. Individuals who have a family history of rock formation are likely to have calcium stones and to have them more frequently. Individuals who have undergone surgery for weight loss (bariatric surgery) may also be at increased risk of stone formation.
Seldom, drugs (including indinavir) and materials in the diet (for example melamine) cause stones.
Rocks, particularly miniature ones, may not cause any symptoms. Kidney stone pain may be caused by stones in the bladder in the lower abdomen. Renal colic is defined by an intermittent pain that was excruciating, generally in the region between the ribs and hip, that spreads across the abdomen and frequently goes to the genital region. The pain has a tendency to come in waves, slowly increasing to some peak intensity, then fading, around about 20 to 60 minutes.
Other symptoms include nausea and vomiting, restlessness, sweating, and blood or a stone or a section of a stone in the urine. Someone may have an urge to urinate often, especially as a rock passes down the ureter. Chills, fever, burning or pain during urination, cloudy, foul-smelling urine, and stomach swelling occasionally occur.
Doctors generally guess stones in people who have renal colic. Occasionally physicians imagine rocks in people with groin or pain in the genital area and tenderness over the back without an obvious cause. Sometimes, physical examination findings and the symptoms are so distinctive that no additional tests are needed, especially in those who have had urinary tract rocks before. Yet, most people are in so much pain and have symptoms and findings which make other causes for the pain appear not unlikely that testing is essential to exclude these other causes.
Helical (also called spiral) computed tomography (CT) that's done without the use of radiopaque contrast material is typically the best diagnostic procedure. CT can locate a rock as well as suggest the level to which the stone is obstructing the urinary tract. Many other illnesses that can cause pain similar to the pain caused by stones can be also detected by cT. The principal disadvantage of CT is that it exposes individuals to radiation. When potential causes comprise another serious disorder that would be diagnosed by CT, such as for instance an aortic aneurysm or appendicitis however, this risk seems prudent. Newer CT apparatus and systems that limit exposure to radiation are actually usually used.
Ultrasonography will not expose people to radiation and is an alternative to CT. Nonetheless, ultrasonography, compared with CT, more often misses small stones (especially when located in the ureter), the exact location of urinary tract blockage, and other, serious ailments that could be causing the symptoms.