Urinary stones--or urolithiasis--can be a painful condition. When the stones form inside the bladder they can cause obstruction and impede urine flow. Depending on its size, a bladder stone can be treated by drinking a lot of fluids to flush the stone from the bladder. Larger stones may require endoscopic intervention to break or remove them. Sometimes the largest stones require surgery to extract them.
Urinary Stone Formation
Urinary stones can form in the kidneys, urinary tract and bladder of humans, dogs and cats. While the term "bladder stones" is most commonly associated with veterinary medicine, the problem does exist in humans. Urinary stones are solid accumulations of mineral salts and other components. Most of the time these stones are small, and pass harmlessly into the urine and then excreted naturally.
Other times they can grow to large sizes and produce pain and other problems. It is not well understood why stones sometimes grow in size while other times they do not. There are four types of stones, according to their composition, called calcium, uric acid, cystine and struvite stones. According to the website eHealthMD, in the U.S. and other developed countries stones in the kidneys are most common. In developing countries, bladder stones are the most common.
Struvite Stones
Struvite stones are also called "magnesium ammonium phosphate stones" since they are composed mostly of those substances. The stones resemble hard crystals and are usually formed because a person has a bacterial infection of the urinary system. Such infection creates an imbalance in the urine's acid concentration. The stones develop when the urine pH is higher than 7.2 and also when ammonia is in the urine. Bacteria are a main cause of abnormal ammonia production in the urine. Since women are more susceptible to urinary tract infections, these stones are twice as common in women compared to men, according to the Stone Center, a urology practice.
Non-Dietary Causes
According to the Department of Urology of the University of Florida (UF), family history and medical conditions are the primary non-dietary causes of urinary stones. A person can be 2.5 times more likely to develop stones if a family member has them. Also, conditions causing chronic diarrhea such as Crohn's disease, inflammatory bowel disorder and gastric bypass are associated with stone formation, also called stone disease. Additionally, hyperparathyroidism, gout, obesity and diabetes may increase the risk of stone disease.
Dietary Risk Factors
The composition of the urine is influenced by diet, volume of food, and the kidney's function. Foods high in animal protein such as red meats, oxalate and salt are risk factors for developing stones. Low urine volumes and low calcium intake also may cause stones, says UF's Department of Urology.
Urinary Risk Factors
Most people with stones have identifiable urinary risk factors. The urinary practice group, Stone Center says that these risk factors include high urine levels of magnesium, calcium, oxalate and uric acid. This may be due to chronic metabolic acidosis as a result of chronic diarrhea. Also, low levels of urine citrate and/or a urinary tract infection are risk factors.
