Medically Reviewed by Dr. David Costa Navarro
Urinary stones are hard, abnormal crystalline formations, mainly composed of mineral salts that can form in any part of the urinary tract (kidney, ureter, bladder, urethra) and are the cause of pain, obstruction and infection. Their origin may be due to factors that increase the concentration of salts in the urine (e.g. reduction in the volume of urine produced or greater elimination of substances that can give rise to stones such as calcium salts, oxalates, urates, phosphates, etc. .). Their formation is also favored by the urinary stasis, for the greater time available for the crystallization of the salts and by other factors such as the greater or lesser acidity of the urine. Calculations containing calcium salts are the most common; uric acid stones are often associated with gout, or with high urine acidity. Finally, mixed composition stones (e.g. calcium phosphate, magnesium ammonium phosphate) can arise following a high urinary pH or after a bacterial infection.
How they manifest
Sometimes, if there is no obstruction of the flow of urine, the presence of a stone can be asymptomatic, that is, not cause disturbances. Often, however, a urinary calculus can cause a renal colic that manifests itself with intermittent pain, very violent, which usually originates in the side or the lower back and radiates through the abdomen along the course of the ureter, frequently in the region of the genitals and on the inner side of the thigh. The stones, if present in the bladder, can cause pain in the area above the genitals. Other symptoms may include burning when urinating, the presence of blood and protein in the urine, recurrent urinary tract infections, retching, chills and fever.
What are the risks
The greatest risk is the development of urinary tract infections.
What should be done
Many small solitary stones, not complicated by obstruction or infection, do not need specific therapy. If, however, the stones are associated with obstruction and infection, they must be surgically removed. Sometimes extraction through the urethra is possible, but today the destruction of stones with ultrasound (lithotripsy) is increasingly used. In case of renal colic, rest, local application of heat and immediate contact with the doctor are necessary. Since the substances that form the calculation derive from the food components it is necessary to follow the following hygienic-dietary rules, depending on the type of calculation:
- calcium stones: meat diet, few vegetables, exclude eggs, milk and dairy products in general
- uric acid stones: reduce meat and animal foods (brain, kidney, heart, liver, kidneys, goose, game, anchovies, herring, sardines, crustaceans). It is useful to drink alkaline or alkalized mineral waters
- calcium oxalate stones: avoid vegetables (spinach, tomatoes, etc.) and especially unripe fruit, cocoa, chocolate. In any case, it is always important to increase the amount of urine produced by drinking at least 2 liters of liquid per day