Many hospitalizations are caused by urinary tract stones. Primary urinary stones are formed as a result of excessive secretion of salts similar to uric acid and cystine. In hyperparathyroidism, stone formation is facilitated by excess excretion of calcium and phosphorus. Excess absorption of oxalates contributes to hyperoxaluria and also to the formation of urinary stones. Secondary stones develop in the presence of foreign bodies, obstruction, reflux, or prolonged bed rest. The use of microorganisms and urea leads to the formation of ammonium-magnesium-phosphate stones.
Calcium oxalate stones occur in 75% of cases. Ammonium-magnesium-phosphate stones infect urine and account for 15%. Uric acid stones account for 8% of all stones. Cystine stones are found only in 1% of cases.
Ureteral stones present clinically with typical colic. Some stones may be asymptomatic and the urine test may be negative. Approximately 90% of stones are radiopaque. With the help of general intravenous pyelography, stones are diagnosed and additional information about the obstruction is obtained. Retrograde pyelography, ultrasonography, and CT examination help in the differential diagnosis.
In severe renal colic, analgesics are required to relieve pain. X-ray examination will be necessary when choosing a treatment. 93% of all ureteral stones are less than 4 mm in diameter and are able to pass on their own. In patients on expectant management, periodic renal function tests should be performed.
Indications and methods of removal
The mere discovery of a stone in the urinary tract does not justify intervention. Recent technical innovations have significantly changed readings. The technique that allows destroying stones with a direct shock wave is designed in Germany. Extracorporeal shock wave lithotripsy is the method of choice for the majority of stones. The procedure is non-invasive and, importantly, reduces the number of complications in the postoperative period. A great inconvenience arises during the subsequent removal of fragments, which can cause obstruction of the ureter and the development of colic. Urinary system stones are available for endoscopic technique. There are all sorts of options for energy sources for breaking stones. With the combined use of ureteroendoscopy,
The technique described above is applicable to the treatment of most urinary stones. Surgical removal of staghorn stones is still performed according to clinical indications. Some authors recommend open online access. Rarely, large bladder stones are removed by cystolithotomy. Some stones can be dissolved by irrigation; uric acid stones dissolve under the action of alkalis, infected stones – under the action of renacidin.
They are used in the formation of percutaneous nephrostomy and are more selective in emergency situations.
As a rule, the formation of stones is a recurrent process, and most patients have a corresponding history. Hydration is one of the most important factors in the prevention of stone formation. Some stones form rapidly at a certain urine pH; you will need mandatory treatment for urinary tract infections, you also need to follow the diet. A low-protein diet is useful for non-cardinal levels of uric acid excretion in the urine. A low oxalate diet is effective in preventing the formation of related stones. In addition, a low-calcium diet is helpful in removing calcium-containing stones. A decrease in the level of calcium in the urine occurs when hydrochlorothiazides or binders (adsorbents) containing cellulose phosphate are used. AllopurinolStops the formation of uric acid stones.
Most patients with hyperparathyroidism have calcium stones. Patients with recurrent stone formation undergo a biochemical blood test (an increase in serum calcium, alkaline phosphatase activity and a decrease in phosphorus) and determine the content of parathyroid hormone in serum. Treatment consists of surgical removal of the adenoma within the thyroid glands.