Kidney stone disease is one of the most common diseases of the urinary system. It is characterized by the appearance of stones in the renal pelvis. These stones are composed of salts, which are present in small amounts in the normal composition of urine. The disease can be diagnosed using several research methods.
To identify stones (calculi) in the kidneys, first of all, pass a general (clinical) urine test. If salt crystals are found in it, this will be an indirect sign of kidney stones. Determining the type of salt can provide preliminary information about the chemical composition of the stones. For example, if oxalates have been detected in the urine, there is a high likelihood of calcium oxalate calculus in the kidneys.
An important indicator is the acidity (pH) of urine. If it is 7, 0, urine is considered neutral, at pH below 7, 0 - acidic, and above 7, 0 - alkaline. In patients with uric acid stones, urine has a more acidic reaction, and in patients who have stones due to infection, urine is alkaline. Crystals of uric acid at pH less than 6.0 are characteristic of urate nephrolithiasis and uric acid diathesis. Crystals of magnesium and calcium at urine pH above 7, 0 indicate phosphate urolithiasis and phosphaturia, calcium oxalates are characteristic of calcium oxalate urolithiasis or oxaluric diathesis.
If bacteria were found in the urine, this may indicate the presence of struvite calculus or a concomitant infectious complication of kidney stones. With any type of calculus, leukocytes are almost always present in the urine. Your doctor may order a 24-hour urine sample (collected over 24 hours). This study is necessary to assess the volume of urine excreted per day, to determine the level of acidity and identify salts and crystals in it.
If you suspect kidney disease, take blood tests: general and biochemical. As a rule, kidney stones do not cause strong changes in the indicators of the clinical (general) blood test, however, with a complication of the disease (pyelonephritis, renal colic), an increase in the level of leukocytes may be observed. A biochemical blood test allows you to determine the level of creatinine, urea, uric acid, etc. Normally, urea should be up to 8, 7 mmol / l, an increase in its level in the blood indicates a decrease in kidney function, which is one of the symptoms of renal failure.
The rate of creatinine in the blood is up to 115 μmol / l. An increase in its level is a symptom of a decrease in kidney function, renal failure. Normally, urea is: in men - 214-458 μmol / l, in women - 149-404 μmol / l. An increase in this indicator may indicate an increased formation of uric acids, that is, urate nephrolithiasis. This phenomenon is observed with urolithiasis with the formation of urates, with gout.