Calculous pyelonephritis is an inflammatory lesion of the calyx-pelvic system of the kidneys, initiated or supported by stone formation. Symptoms include lumbar pain, weakness, in acute form – hyperthermia with chills, dysuria. The diagnosis is based on laboratory research methods: urine test, blood test, chemical analysis of the stone. Of the instrumental methods, ultrasound of the kidneys, non-contrast spiral CT of the abdominal cavity and pelvis are used. Treatment in the absence of a pronounced urodynamic disorder and small concretions is conservative, for complicated cases – operative, aimed at restoring the passage of urine, combined with antibiotic therapy.
ICD 10
N20 Kidney and ureter stones
Meaning
The global incidence of calculous pyelonephritis increases annually by 0.5-5.3%. Mostly the diagnosis is made at the age of 20-50 years. In men, pathology is registered more often, which is potentially associated with hormonal changes. The disease takes a recurrent form, therefore, specialists in the field of clinical urology consider adequate metaphylaxis of ICD and calculous pyelonephritis to be a priority. The complexity of therapy is due to the fact that pathogenic microorganisms contribute to stone formation, and if the stone was formed in the absence of infection, infection and subsequent inflammatory reaction potentiate its growth and the formation of new concretions.
Causes
The main cause of inflammation of the cup-pelvic structure in kidney stones is the secondary attachment of pathogenic microflora against the background of urostasis. There is a vicious circle: uronephrolithiasis can develop with existing pyelonephritis, and inflammation contributes to stone formation. Stones differ in salt composition, as well as the processes that led to the formation of a particular type of concretion. The risk of kidney inflammation increases in people with immunosuppression, burdened by a family history of ICD, when living in areas with low-quality water. Pathology is provoked:
- Oxalate nephrolithiasis. The cause of hypercalciuria and hyperoxaluria is an increased consumption of oxalates with a diet high in beetroot, beans and dark green vegetables, an overabundance of vitamin C, diseases associated with malabsorption of bile acids or chronic diarrhea (Crohn’s disease, short bowel syndrome, conditions after abdominal surgery). Ethylene glycol poisoning and pyridoxine deficiency are considered as possible triggers of calcium oxalate synthesis, triggering the development of calculous inflammation. This is the most common type of nephrolithiasis (80%).
- Phosphate nephrolithiasis. Hyperparathyroidism and renal tubular acidosis of type 1 lead to the formation of calcium phosphate concretions. Primary hyperparathyroidism is characterized by increased activity of parathyroid hormone due to an increase in its secretion by the parathyroid glands. Secondary hyperparathyroidism occurs in response to a decrease in blood calcium levels, malignant is observed with the secretion of parathyroid protein by some tumors. Among the common causes are autoimmune diseases, hypercalciuria, taking medications containing phosphamide and lithium.
- Uric acid stones. They are formed against the background of hyperuricemia and hyperuricosuria. Hyperuricemia is an increase in the concentration of uric acid in the blood serum (≥7 mg / dl for men; ≥6.0 mg / dl for women) against the background of its overproduction in malignant neoplasms, hemolytic anemia, increased consumption of purine (alcohol, protein). Hyperuricosuria – increased uric acid excretion >800 mg / day in men, >750 mg/ day in women. Nephrolithiasis is accompanied by calculous pyelonephritis (90-95%), gout (25%). Formations of uric acid salts occur in 10%.
- Struvite concretions. The removal of urine using a constantly functioning catheter creates a high risk of contamination of urease-producing bacteria: protea mirabilis, klebsiella, ureaplasm urealyticum, which leads to persistent urinary tract infections. Pathologies that violate the passage of urine (compression of the ureter from the abdominal cavity, infravesical obstruction, tumors, ureter valves) are complicated by reflux with the formation of struvite stones and are accompanied by secondary inflammation.
- Cystine stones. Autosomal recessive disorder with metabolic disorders is characterized by defective intestinal or renal tubular excretion of dibasic amino acids, these mechanisms serve as the basis for the formation of cystine concretions. They occur in 1% of cases. Examples of diseases are phenylketonuria, cystinuria. Concomitant calculous infectious pyelonephritis is registered in some patients, but metabolic nephropathy becomes the cause of renal failure.
There are a number of predisposing factors for the development of secondary pyelonephritis. Diuretics enhance the excretion of uric acid, which contributes to the growth of stones, strengthening the perifocal inflammatory reaction. Behavioral factors include low fluid intake, a diet rich in purine bases, and a sedentary lifestyle. Hypothermia in urolithiasis, extragenital infection, mechanical traumatization (concretion, shaking riding) can lead to an exacerbation of concomitant pyelonephritis.
Pathogenesis
Calculous pyelonephritis has a secondary character in relation to stone formation, develops due to a violation of the evacuation of urine from the pelvis. A complete block provokes purulent inflammation with a sharp increase in intra-pulmonary pressure. Urine continues to flow into the pelvis, causing its expansion, which is accompanied by pain. There is an activation of prostaglandin synthesis, an increase in renal blood flow, glomerular filtration. The contractile function of the upper urinary tract is enhanced by the action of biologically active substances, then comes discoordination and then atony.
Urostasis initiates severe hemodynamic disorders, leads to ischemia, swelling of paranephral tissue and tissue hypoxia. In patients with uronephrolithiasis, urodynamics suffers in 90% of cases, which is why bacteria, products of their vital activity and vasoactive substances accumulate in the kidneys. High hydrostatic pressure potentiates the spread of uropathogens into the kidney parenchyma and bloodstream. Of particular importance for the development of inflammation are fornical and tubular reflux, contributing to the discharge of infected urine into the bloodstream and urinary tubules.
Classification
Calculous pyelonephritis can be unilateral or bilateral, the latter occurs in 30% of cases. In form, it is always secondary, with metabolic disorders, the process is usually detected in both kidneys. Long-term urolithiasis and inflammation are accompanied by CRF. Kidney stones can be single or multiple, their sizes are variable, with coralloid nephrolithiasis, the concretion occupies the entire cup-pelvic system. According to the nature of the flow , the following forms are distinguished:
- Spicy. The clinical picture is usually caused by an inadequate outflow of fluid from the heart against the background of an obstacle. The more pronounced the obstruction, the more intense the symptoms. The process is more often one-sided, it is possible to involve the ipsilateral kidney, since uropathogens hematogenically affect a neighboring organ working with an increased load.
- Latent. Sedentary concretions localized in cups and pelvises rarely prevent the evacuation of urine, but provoke discoordination of contractile activity of the urinary tract, ischemia. The inflammatory process proceeds sluggishly, pronounced symptoms are more often absent, signs of trouble are judged by changes in urine analysis.
- Chronic. Symptoms appear when concretions move, as they grow or synthesize new ones. Despite the changes in the tests, the temperature reaction is usually not detected, the general well-being suffers slightly.
Taking into account the activity of pyelonephritis against the background of ICD, it is either in the active stage or in the stage of incomplete clinical and laboratory remission; normalization of tests and relief of exacerbation are possible only after removal of concretions, massive antimicrobial therapy, preventive measures. The active process, compared with the latent course, has a higher probability of transition to a shrunken kidney or calculous pyonephrosis, which in some classifications is considered as the outcome of secondary pyelonephritis.
Symptoms
Clinical manifestations depend on a number of factors: the severity of urodynamic disorders, the activity of inflammation, the localization of the obstacle. In the latent form, there are no symptoms. Acute inflammatory process is manifested by an increase in temperature with terrific chills, cloudy urine (sometimes with blood) after an attack of renal colic, dysuria. Hematuria indicates the movement of concretions, rupture of the fornic vessels. Common symptoms include weakness, headache, musculoskeletal ache. Due to irritation of the solar plexus, flatulence, nausea, vomiting are observed.
Muscle spasm, increased peristalsis, local inflammation and edema contribute to the appearance of pain through the activation of chemoreceptors and irritation of nerve endings. The intensity of sensations depends on the pain threshold, the speed and degree of change in hydrostatic pressure in the kidney and ureter. Urethral peristalsis, migration of the stone increase the pain syndrome. The patient often points to the place of maximum soreness, which is potentially the localization of obstruction in secondary pyelonephritis. The irradiation of pain is variable, associated with the location of the concretion.
Complications
Complications of calculous pyelonephritis can be acute or chronic. With bilateral blocking of the ureters, acute renal failure develops. If untimely assistance is provided or antibacterial drugs are prescribed without the permission of obstruction, bacteriotoxic shock or urosepsis is possible. The infection can spread from the kidney to nearby tissues with the development of peri- and paranephritis (inflammation of the perinephrine tissue).
Chronic complications include persistent arterial hypertension, poorly amenable to drug correction, hydronephrotic transformation (in severe cases – calculous pyonephrosis), the addition of chronic renal failure. Frequent relapses of urolithiasis, concomitant inflammation lead to secondary wrinkling of the kidneys. Sometimes the only possible treatment option is hemodialysis, since kidney transplantation is not always possible with metabolic disorders.
Diagnostics
The main purpose of the diagnosis is to establish the degree of obstruction of the upper urinary tract to determine the tactics of patient management. The patient’s family history, eating habits are found out, they are interested in concomitant pathology and taking medications. Primary measures include visualization techniques and laboratory tests aimed at determining the severity of the inflammatory reaction, the preservation of kidney function. Diagnostic algorithm for calculous inflammatory process:
- Instrumental examination. Ultrasound of the kidneys shows the presence of stones (65%), the degree of expansion of the heart, the condition of the ureter. The method is preferable for pregnant women, children. Excretory urography is possible only if there are no signs of kidney blockage according to the analysis data. Urograms give an idea of the functional ability of both kidneys, VMP anomalies, but they do not always visualize concretions. For adults, the study of choice is a CT of the retroperitoneal space, which allows you to assess the density of stones, their localization and anatomical features.
- Laboratory examination. A large number of leukocytes and bacteria in the general analysis of urine does not always correlate with the severity of the process, achieving complete laboratory remission with kidney stones is often impossible. Of great importance for further treatment is the pH of urine, crystal microscopy. The study of the composition of the concretion with high reliability makes it possible to find out the structural basis. Bakposev is necessary for the determination of pathogens. Metabolic evaluation is indicated for recurrent nephrolithiasis: the level of calcium, phosphorus, uric acid is examined.
Differential diagnosis is carried out with an acute abdomen: appendicitis (right-sided nephrolithiasis), intestinal obstruction, peritonitis. Similar manifestations can be found in non-obstructive pyelonephritis, cystitis. To exclude abdominal pathology, the urologist prescribes a consultation with a surgeon, for the same purpose, ultrasound of the abdominal organs is performed. In doubtful cases, diagnostic laparoscopy is performed, especially if gynecological diseases are suspected.
Treatment
Before determining the treatment tactics, the degree of urinary evacuation disorder is established. Hyperthermia in a patient with previously diagnosed urolithiasis, uncupable renal colic are indications for hospitalization in a urological hospital. Concretions up to 7 mm can come out on their own, the patient’s condition is monitored in dynamics. If hydronephrotic transformation increases on sonograms, and laboratory tests indicate an increase in creatinine levels, an active management tactic is recommended. Pathology treatment can be conservative or operative.
Drug therapy
First–line drugs are antimicrobial agents with the widest possible spectrum of action, suitable for empirical use. Concomitant renal colic is eliminated with the help of antispasmodics, analgesics (sometimes narcotic), nonsteroidal anti-inflammatory drugs. Expulsive therapy involves the appointment of alpha-blockers. Deterioration of health, lack of positive dynamics – an indication for surgical intervention, urological manipulation.
Surgical treatment
10-20% of patients need surgical treatment, which is associated with the need to restore urodynamics. Organ-bearing operations are justified for pionephrosis, acute purulent stone pyelonephritis without response to therapy. Pyelonephritis with stones over 10 mm, pronounced concomitant obstruction and the threat of urosepsis also implies an active approach:
- Ureteral stenting, nephrostomy. Palliative interventions are carried out to normalize the flow of urine, after which antibiotics, uroseptics, litolytic drugs are prescribed. The stent is inserted into the kidney transureterally during therapeutic and diagnostic ureteropyeloscopy. If an unsuccessful attempt is made to stent the ureter, a nephrostoma is formed under ultrasound control. After the elimination of inflammation, radical operations are possible.
- Removal of concretions. Extracorporeal shock wave lithotripsy is performed in the presence of renal and ureteral stones < 20 mm during remission of calculous pyelonephritis. The technique is contraindicated in pregnancy, pathology of the blood coagulation system, severe obesity. Percutaneous nephrolithotomy is suitable for removing concretions of more than 20 mm. Laparoscopic or open pyelolithotomy, ureterolithotomy is rarely performed with the ineffectiveness of the above methods or with complicated stones with high density.
Prognosis and prevention
With timely adequate treatment, correction of metabolic disorders, following medical recommendations, the prognosis for life is favorable. CRF, acute renal failure, kidney shrinkage, recurrent course negatively affect the outcome. The recurrence rate of urolithiasis reaches 50% within 5 years, 70% or higher within 10 years. Repeated stone formation after the first episode of ureterolithiasis is 14%, 35% and 52% for 1, 5 and 10 years, respectively.
Prevention involves strengthening the drinking regime, following a diet depending on the chemical structure of stones, taking litolytic drugs, uroseptics. Phytotherapy can be used as an auxiliary measure. Patients are subject to medical examination by a urologist or nephrologist with monitoring of urine, blood and biochemical parameters, ultrasound scanning every 6-12 months. It is equally important to sanitize any infectious foci in a timely manner – to treat carious teeth and chronic uroinfections (prostatitis, cystitis, urethritis).