Question: What is (are) Kidney Stones in Adults ?
Answer: A kidney stone is a solid piece of material that forms in a kidney when substances that are normally found in the urine become highly concentrated. A stone may stay in the kidney or travel down the urinary tract. Kidney stones vary in size. A small stone may pass on its own, causing little or no pain. A larger stone may get stuck along the urinary tract and can block the flow of urine, causing severe pain or bleeding. Kidney stones are one of the most common disorders of the urinary tract. Each year in the United States, people make more than a million visits to health care providers and more than 300,000 people go to emergency rooms for kidney stone problems.1 Urolithiasis is the medical term used to describe stones occurring in the urinary tract. Other frequently used terms are urinary tract stone disease and nephrolithiasis. Terms that describe the location of the stone in the urinary tract are sometimes used. For example, a ureteral stoneor ureterolithiasisis a kidney stone found in the ureter.
Source: NIDDK

Question: What is (are) Kidney Stones in Adults ?
Answer: The urinary tract is the bodys drainage system for removing wastes and extra water. The urinary tract includes two kidneys, two ureters, a bladder, and a urethra. The kidneys are two bean-shaped organs, each about the size of a fist. They are located near the middle of the back, just below the rib cage, one on each side of the spine. Every day, the two kidneys process about 200 quarts of blood to produce about 1 to 2 quarts of urine, composed of wastes and extra water. The urine flows from the kidneys to the bladder through tubes called ureters. The bladder stores urine until releasing it through urination. When the bladder empties, urine flows out of the body through a tube called the urethra at the bottom of the bladder.
Source: NIDDK

Question: What causes Kidney Stones in Adults ?
Answer: Kidney stones can form when substances in the urinesuch as calcium, oxalate, and phosphorusbecome highly concentrated. Certain foods may promote stone formation in people who are susceptible, but scientists do not believe that eating any specific food causes stones to form in people who are not susceptible. People who do not drink enough fluids may also be at higher risk, as their urine is more concentrated. People who are at increased risk of kidney stones are those with - hypercalciuria, a condition that runs in families in which urine contains unusually large amounts of calcium; this is the most common condition found in those who form calcium stones - a family history of kidney stones - cystic kidney diseases, which are disorders that cause fluid-filled sacs to form on the kidneys - hyperparathyroidism, a condition in which the parathyroid glands, which are four pea-sized glands located in the neck, release too much hormone, causing extra calcium in the blood - renal tubular acidosis, a disease that occurs when the kidneys fail to excrete acids into the urine, which causes a persons blood to remain too acidic - cystinuria, a condition in which urine contains high levels of the amino acid cystine - hyperoxaluria, a condition in which urine contains unusually large amounts of oxalate - hyperuricosuria, a disorder of uric acid metabolism - gout, a disorder that causes painful swelling of the joints - blockage of the urinary tract - chronic inflammation of the bowel - a history of gastrointestinal (GI) tract surgery Others at increased risk of kidney stones are people taking certain medications including - diureticsmedications that help the kidneys remove fluid from the body - calcium-based antacids - the protease inhibitor indinavir (Crixivan), a medication used to treat HIV infection - the anti-seizure medication topiramate (Topamax)
Source: NIDDK

Question: What is (are) Kidney Stones in Adults ?
Answer: Four major types of kidney stones can form: - Calcium stones are the most common type of kidney stone and occur in two major forms: calcium oxalate and calcium phosphate. Calcium oxalate stones are more common. Calcium oxalate stone formation may be caused by high calcium and high oxalate excretion. Calcium phosphate stones are caused by the combination of high urine calcium and alkaline urine, meaning the urine has a high pH. - Uric acid stones form when the urine is persistently acidic. A diet rich in purinessubstances found in animal protein such as meats, fish, and shellfishmay increase uric acid in urine. If uric acid becomes concentrated in the urine, it can settle and form a stone by itself or along with calcium. - Struvite stones result from kidney infections. Eliminating infected stones from the urinary tract and staying infection-free can prevent more struvite stones. - Cystine stones result from a genetic disorder that causes cystine to leak through the kidneys and into the urine, forming crystals that tend to accumulate into stones.
Source: NIDDK