Coral nephrolithiasis (coral stones in the kidney)

Coral stones in the kidneys (coral nephrolithiasis) - an independent disease that differs from all other forms of urolithiasis features of pathogenesis and has its clinical picture.

Epidemiology of coral stones in the kidneys

Coronal stones in the kidneys are quite common (according to various data, in 3-30% of cases of detection of normal kidney stones). The disease is diagnosed 2 times more often in women than in men; in 68% of cases - in people aged 30-50 years.

[1], [2]

What causes coral stones in the kidneys?

Coral stones in the kidneys develop against the background of violations of hemo- and urodynamics and is complicated by pyelonephritis, which leads to a progressive decrease in kidney function. Occurrence of coral nephrolithiasis is most conducive to various congenital and acquired tubulo- and glomerulopathies, which are based on enzymes. The most common enzyme pathogenesis in coral nephrolithiasis leads to oxaluria (85.2%); Tubulopathies leading to fructosuria, galactosuria, tubular acidosis, and cystinuria are much less common. If these factors are the determining factors in the development of the disease, then all other exogenous and endogenous factors act only as conducive to the development of the disease, i.e. Less significant. The climatic conditions are of special importance, especially for persons who have changed their place of residence to hot countries, water, food products, and atmospheric pollution. Stone formation is facilitated by diseases of the digestive tract, liver, hyperfunction of parathyroid glands, fractures of bones requiring prolonged bed rest. In some cases, the formation of coral stones during pregnancy is noted, which is caused by disturbance of the water-electrolyte attention of urodynamics, hormonal changes. A number of researchers draw attention to the role of hereditary factors in the development of the disease, which constitute about 19%.

Many authors etiological factor of nephrolithiasis. Acting in 38% of cases, consider hyperparathyroidism. Despite the obvious changes in the patient's body with primary hyperparathyroidism, it is not possible to prove the leading role of the change in the function of parathyroid glands in the formation of kidney stones. The triad of symptoms of primary hyperparathyroidism (hypercalcemia, hypophosphatemia and hypercalciuria) is not typical for all patients with coral nephrolithiasis, and not all hyperparathyroid patients have coral stones.

For diagnostics of adenoma of parathyroid glands, ultrasound and radioisotope scintigraphy are most often used.

At the same time, the cause of kidney stones in general and coral ones in particular remains an unsettled issue, which creates difficulties in developing tactics for treating patients with coral nephrolithiasis, effective prevention of stone formation and its recurrence.

How do coral stones develop in the kidneys?

The core of most stones is formed by an organic substance. However, when studying the chemical composition of stones, it is established that their formation can begin on an inorganic basis. In any case, for the formation of stones, even with the supersaturation of urine with salts, a binding component is needed, which is an organic substance. Such an organic matrix of concrements are colloid bodies with a diameter of 10-15 microns, found in the lumen of the tubules and lymphatic capillaries of the stroma. The composition of colloid bodies revealed glycosaminoglycans and glycoproteins. In addition to the usual components (cystine, phosphate, calcium, urate, etc.), the composition of the stone includes mucoproteins and plasma proteins of different molecular weight. Most often it is possible to detect the uromucoid. Albumin and immunoglobulins IgG and IgA.

The most interesting data were obtained by immunochemical analysis of the urine protein composition, in which urinary excretion of small plasma proteins such as alpha-acid glycoprotein, albumin, transferrin and IgG was detected, which is a sign of the tubular type of proteinuria, but sometimes proteins of greater molecular weight , such as IgA and a2-macroglobulin.

These proteins penetrate into the secondary urine due to a violation of the structural integrity of the glomeruli, namely the glomerular basal membranes. This confirms the data that coral stones in the kidneys are accompanied not only by tubular disorders but also by glomerulopathy.

Electron microscopic studies of kidney tissue revealed abnormalities in the site of the plasmalemma, which ensures the processes of mandatory and facultative reabsorption. In nephrocytes of the renal tubules of the proximal and distal sections, changes in the microvilli of the brush border were detected. Electronically loose flaky material was found in the lumen of Henle's loop and collecting tubes.

The nuclei of the cells lining the Henle loop are always deformed, and the largest changes are found in the basal membrane.

Studies have shown that with coral nephrolithiasis, the renal parenchyma is changed in all departments.

The study of the immune status of patients according to the results of the analysis of blood and urine showed no significant deviations from the norm.

Symptoms of coral stones in the kidneys

Symptoms of corvoid nephrolithiasis are nonspecific, as well as complaints peculiar only to patients with this disease.

With detailed analysis, it can be noted that the clinical picture is expressed by symptoms of disturbance of urodynamics and kidney function.

Based on the clinical picture, four stages of coral nephrolithiasis are distinguished:

• I - the latent period;
• II - onset of the disease;
• III - stage of clinical manifestations;
• IV - hyperazotemic stage.

I stage is called a latent period, because at this time there are no bright clinical manifestations of kidney disease. Patients complain of weakness, increased fatigue, headache, dry mouth and chills.

The onset of the disease (stage II) is characterized by mild blunt pain in the lumbar region and sometimes intermittent changes in the urine.

At the stage of clinical manifestations (stage III), dull pain in the lumbar region is constant, subfebrile temperature appears, and fatigue, weakness and malaise progress. Often there is hematuria and the passage of small stones, accompanied by renal colic. There are signs of chronic renal failure - a latent or compensated stage.

In IV stage - hyperazotemic - patients complain of thirst, dry mouth, general weakness, increased fatigue, pain in the lumbar region, dysuria and symptoms of exacerbation of pyelonephritis. This stage is characterized by intermittent or even terminal stage of chronic renal failure.

Classification of coral stones in the kidneys

Depending on the size and location of the coral stone in the cup-and-pelvis system and its configuration, four stages of coral nephrolithiasis are distinguished:

• Coronal nephrolithiasis-1 - concrement performs a pelvis and one of the cups;
• Coronal nephrolithiasis-2 - is located in the pelvis of the extrarenal type with processes in two or more cups;
• Coronal Nephrolithiasis-3 - located in the pelvis of the intrarenal type with processes in all calyxes;
• Coralloid nephrolithiasis-4 has processes and performs the entire deformed bowel-cup system.

Retinal changes in coral nephrolithiasis are diverse: from moderate pyeloectasia to total expansion of not only the pelvis, but all cups.

The main factor in choosing a method of treatment is the degree of impaired renal function. The four phases of impaired renal function reflect a deficiency in their secretory capacity:

• Phase I - tubular secretion deficiency 0-20%;
• Phase II - 21-50%;
• Phase III - 51-70%:
• IV phase - over 70%.

Thus, with the help of this classification, which makes it possible to evaluate the size and configuration of the stone, the ectasia of the bowel-cup system, the degree of renal dysfunction and the stage of the inflammatory process, they develop indications for this or that method of treatment.

Diagnosis of coral stones in the kidneys

Coronal stones, as a rule, are detected accidentally with ultrasound or on a survey roentgenogram of the urinary tract.

Diagnosis of coral nephrolithiasis is based on general clinical signs and data from additional research.

Patients with coral stones in the kidneys often increased blood pressure. The cause of arterial hypertension is the violation of hemodynamic equilibrium.

Concomitant coral nephrolithiasis chronic pyelonephritis can be diagnosed at any stage of the clinical course.

A detailed study of patients' lifestyle, anamnesis and clinical picture of the disease, radiographic and laboratory data, radioisotope and immunological tests, revealed signs of various stages of chronic renal failure (latent, compensated, intermittent and terminal). It should be noted that due to technical progress and improvement of diagnostic methods over the past decade, patients with coral stones in the terminal stage of chronic renal failure are extremely rare.

GFR in the latent stage of chronic renal failure is 80-120 ml / min with a tendency to gradual decrease. In the compensated stage, GFR is reduced to 50-30 ml / min, in intermittent stage - 30-25 ml / min, in terminal - 15 ml / min. The pronounced weakening of glomerular filtration always leads to an increase in urea and creatinine in the blood serum. The sodium content in the plasma fluctuates within normal limits, excretion is reduced to 2.0-2.3 g / day. Often observed hypokalemia (3.8-3.9 meq / l) and hypercalcemia (5.1-6.4 meq / l). In the compensated stage of chronic renal failure, polyuria occurs, which is always accompanied by a decrease in the relative density of urine. The change in protein metabolism leads to proteinuria, dysproteinemia, hyperlipemia. A relative increase in aspartate aminotransferase activity and a decrease in serum alanine aminotransferase activity were noted.

In chronic renal failure in patients with coral stones in the number of uroproteins found plasma proteins: acid glycoprotein, albumin, transferrin. In severe cases, proteins with higher molecular weight get into the urine: immunoglobulins, a2-macroglobulins, beta-lipoproteins. This confirms the assumption of a violation of the integrity of glomerular basal membranes, which normally do not pass these plasma proteins into urine.

Changes in the functional activity of the kidneys are always accompanied by a violation of carbohydrate metabolism, which is caused by an increased content of insulin in the blood.

Dull pain in the lumbar region, weakness, increased fatigue can serve as clinical symptoms of many kidney diseases, such as chronic pyelonephritis, other clinical forms of urolithiasis, polycystic kidney disease, hydronephrosis transformation, kidney tumor, etc.

On the basis of complaints made by patients, one can only suspect kidney disease. The leading place in diagnostics is occupied by ultrasound and X-ray study. Ultrasound in 100% of cases determines the size and contours of the kidney, the shadow In its projection, the size and configuration of the coral stone, establishes the presence of expansion of the cup-and-pelvis system.

On the survey X-ray in the projection of the kidney, the shadow of the coral stone is visible.

Excretory urography allows to more accurately assess the functional activity of the kidneys, confirm the presence of dilatation of the calyx-pelvis system.

[3], [4], [5], [6]

Clinical diagnosis of coral stones in the kidneys

Patients complain of dull pain in the lumbar region, often worse before the onset of renal colic, the escaping of small stones, fever, dysuria, a change in the color of urine. In addition to these symptoms, thirst, dry mouth, weakness, fatigue and itching of the skin appear in the patients. Skin covers are pale, in the most severe group of patients - with a yellowish tinge.

[7], [8], [9]

Laboratory diagnostics of coral stones in the kidneys

Laboratory tests help assess the severity of the inflammatory process. To establish the functional state of the kidneys, other organs and systems. In all patients at the stage of clinical development of the disease, an increase in ESR, leukocytosis and pyuria can be detected.

With a sharp violation of the filtration process, creatinine clearance is reduced to 15 ml / min. An increase in the concentration of amino acids in the blood plasma is associated with impaired liver function.

Instrumental diagnosis of coral stones in the kidneys

Instrumental research methods, in particular, cystoscopy, can identify the source of bleeding in macrohematuria. The ultrasound of the kidneys helps not only to find the coral stone, but also to study its configuration, changes in the renal parenchyma and the presence of dilatation of the cup-and-pelvic system. The main place in the diagnosis of coral calculous kidney stones is allocated by X-ray methods of investigation. A survey image of the urinary tract shows coral stone, you can evaluate its shape and size.

Excretory urography allows to establish the size of the kidney, its contours, segmental changes in nephrograms, slowing of the secretion of contrast medium, accumulation of it in dilated calyces, absence of kidney function.

Retrograde pyelography is performed extremely rarely, immediately before surgery if there is a suspected violation of urodynamics.

Renal angiography allows you to determine the location of the renal artery from the aorta, the diameter of the renal artery and the number of segmental branches. Renal angiography is indicated in cases when nephrotomy is planned for intermittent clamping of the renal artery.

The method of isotope renography with an assessment of the blood clearance allows us to determine the level of functional activity of the kidneys.

Dynamic nephroscintigraphy helps to assess the functional state of not only the affected, but also the contralateral kidney.

Indirect renal angiography is a valuable study that allows to establish qualitative and quantitative violations of hemodynamics in individual segments of the kidneys.

For diagnostics of adenoma of parathyroid glands, ultrasound and radioisotope scintigraphy are most often used.

Treatment of coral stones in the kidneys

A patient with coral nephrolithiasis in stage KH-1, if the disease proceeds without pain, exacerbations of pyelonephritis and renal dysfunction, can be observed in the urologist and receive conservative treatment. Antibacterial drugs are prescribed taking into account the bacteriological analysis of urine. Widely use litholytic drugs, diet and diuretics.

Medication for coral stones in the kidneys

To reduce the formation of uric acid, uricuretics can be prescribed to patients. If necessary, simultaneously recommend nitrate mixtures (blemarene) to maintain the pH of the urine in the range of 6.2-6.8. To increase the pH of urine, you can also use drinking soda at a dose of 5-15 g / day.

In oxaluria, a combination of pyridoxine or magnesium oxide with a mareline provided good results. With hypercalciuria, dairy products are excluded, hydrochlorothiazide is recommended at a dose of 0.015-0.025 g 2 times a day. The level of potassium in the blood is well supported by the introduction of dried apricots, raisins, baked potatoes or 2.0 g of potassium chloride per day into the diet. The use of calcitonin in patients with primary hyperparathyroidism leads to a decrease in hypercalcemia.

To prevent purulent-inflammatory complications, it is necessary to carry out antibiotic prophylaxis.

Operative treatment of coral stones in the kidneys

In those cases when the disease occurs with frequent attacks of acute pyelonephritis. Complicated by hematuria or pionephrosis, surgical treatment is indicated.

The introduction of new technologies - PNL and DLT - reduced the indications for open surgical interventions and largely improved the treatment of a severe category of patients with coral nephrolithiasis. Improved and open surgical interventions aimed at preserving renal parenchyma.

Optimal and most sparing method of coral stone removal at the stages KH-1 and KN-2 is PNL. At these stages this type of treatment is considered as a method of choice, and at the stage of KH-3 as an alternative to open surgical intervention.

DLT is used mainly at the stage of KH-1. It was noted for its high efficiency in children. DLT is effective for stones in the pelvis of the intrarenal type, a decrease in kidney function by no more than 25%, and normal urodynamics against the background of remission of chronic pyelonephritis.

Many authors prefer combination therapy. The combination of open surgery and DLT or PNL and DLT most fully meet the principles of treatment of this category of patients.

Advances in medicine in recent years have allowed to expand indications for open surgical treatment of patients with coral nephrolithiasis. The most gentle open surgery for coral stones in the kidneys is pyelolithotomy lower, posterior subcortical or with the transition to cups (pyelocalocolotomy). However, with pyelolithotomy, it is not always possible to remove stones located in the calyx. The main method of treatment for coral stones in stages KH-3 and KN-remains pyelonephrolithotomy. Execution of one or more nephrotopathic incisions with intermittent clamping of the renal artery (the duration of ischemia usually 20-25 min) does not significantly affect the functional state of the kidney. The operation is completed by setting the nephrostomy.

The introduction of new technologies in the treatment of coral nephrolithiasis (PNL and DLT) reduced the number of complications to 1-2%. Open surgical interventions with appropriate preoperative preparation, improvement of anesthesiology and methods of pyelonephrolithotomy with clamping of the renal artery made it possible to perform organ-saving operations. Nephrectomy with coral stones is performed in 3 5% of cases.

Further management

Coronal stones in the kidneys can be prevented if the dynamic monitoring by a urologist at the place of residence. In exchange disorders (hyperuricuria, hyperuricemia, a decrease or increase in the pH of urine, hyperoxaluria, hypo- or hypercalcemia, hypo- or hyperphosphatemia), it is necessary to prescribe corrective therapy. It is necessary to reduce the amount of food consumed, including fats and table salt, exclude chocolate, coffee, cocoa, by-products, broths, fried and spicy dishes. The amount of fluid consumed must be at least 1.5-2.0 liters per day with normal glomerular filtration. Since the inhibitor of xanthine oxidase allopurinol reduces the level of uricemia, they are indicated in violation of purine metabolism.