Ureterolithiasis are a manifestation of urolithiasis, characterized by the migration of concretion from the renal pelvis to the excretory duct, less often by the primary formation of concretions in the ureter. Disease most often cause the development of renal colic – severe pain syndrome, dysuric disorders, oliguria, hematuria. Diagnosis of a stone in the ureter includes performing an overview radiography of the abdominal cavity, urography, computed tomography. If it is impossible to independently remove the stone from the ureter, ureterolithoextraction, ureterolithotripsy, ureterolithotomy are resorted to.
ICD 10
N20.1 Ureterolithiasis
Meaning
Ureterolithiasis (stones of ureter) in comparison with concretions of other localizations (stones of the bladder, urethra, kidney) are dangerous with the most severe and serious complications. Concretions that disrupt the passage of urine cause loosening of the ureter mucosa, hemorrhages in its submucosal layer, hypertrophy of the muscle wall. Over time, progressive changes lead to atrophy of the muscle and nerve fibers of the ureter, a sharp decrease in its tone, ureterectasia and hydroureteronephrosis. During the infectious process, ascending pyelonephritis develops rapidly in an anatomically altered ureter. Bedsores, strictures, and wall perforations may form in place of a stone that has been in the ureter for a long time.
Causes
Most of the ureteral concretions that practical urology encounters are kidney stones that have shifted from the pelvis. They can have a variety of shapes and sizes. More often, single concretions get stuck in the ureter, but there are also multiple stones of the ureter. Usually, the concretion is delayed in the zones of physiological narrowing of the ureter – the pelvic-ureteral segment, in the area of intersection with the iliac vessels or the vesicoureteral segment.
Primary ureterolithiasis are rare. Their initial formation in the ureter can be facilitated by ureterocele, tumors, ectopia of the ureter, strictures, foreign bodies (ligatures, etc.). Stones of the left and right ureter are detected equally often.
Stone formation in the urinary tract is promoted by alimentary factors – nutritional characteristics and the quality of drinking water. Since the formation of stones is based on a violation of phosphoric acid, oxalic acid, uric acid, etc. types of metabolism, the frequency of urolithiasis correlates with gout, hyperparathyroidism, osteoporosis, bone fractures.
Pathogenesis
The pelvic-ureteral segment is the place of transition of the renal pelvis of a larger diameter into the ureter with a lumen of 2-3 mm. Following the pelvic-ureteral segment, the ureteral lumen expands to 10 mm, so a small stone can shift distally – up to the second physiological narrowing at the level of the iliac vessels. At this point, the ureter crosses the upper border of the entrance to the pelvis and narrows again to a diameter of 4 mm. The third physiological narrowing of the ureter is the vesicoureteral segment, where the diameter of the ureter is 1-5 mm. Approximately 25% of stones get stuck in the upper third of the ureter, about 45% in the middle, and up to 70% in the lower. For retention in the ureter, the diameter of the stone should exceed 2 mm.
In the pathogenesis of stone formation, a change in the pH of urine, a violation of its colloidal state and a decrease in the dissolving ability are of paramount importance. Such changes can develop under the influence of infection, primarily pyelonephritis. A well-known role here is assigned to the factors leading to urostasis – the irregular structure of the cups and pelvis, strictures and valves of the ureter, incomplete emptying of the bladder with urethral stricture, prostate adenoma, diverticula of the urinary tract, spinal cord injuries, etc.
Symptoms
Clinical manifestations of ureteral stones develop with partial or complete blockage of urine outflow from the kidney. Therefore, in 90-95% of patients, ureterolithiasis are detected only with the development of renal colic.
With partial overlap of the ureteral lumen with a stone, the pain is dull, with localization in the corresponding costo-vertebral angle. In the case of complete obstruction of the ureter, a sudden violation of the outflow of urine from the kidney develops, an overgrowth of the pelvis and an increase in intra-pulmonary pressure. Violation of microcirculation in the renal tissue and irritation of nerve endings causes a severe attack of pain – renal colic.
An acute pain attack with a stone in the ureter develops suddenly and is more often associated with physical exertion, fast walking, shaking driving or copious intake of fluids. The pains are localized in the lower back and hypochondrium, radiate along the ureter into the scrotum or labia. Acute pain forces the patient to continuously change position, which, however, does not bring relief. Renal colic can last for several hours or days, periodically subsiding and resuming again.
A painful attack is accompanied by reflex disorders of the gastrointestinal tract – nausea and vomiting, flatulence, stool retention, muscle tension of the anterior abdominal wall. This is due to irritation of the nerve endings of the parietal peritoneum adjacent to the middle third of the ureter. Dysuric disorders depend on the location of the concretion. When the stone is localized in the lower part of the ureter, continuous painful urge to urinate develops, sensations of strong pressure in the suprapubic region due to irritation of the receptors of the walls of the bladder.
Sometimes, when the ureter is obstructed by a stone, oliguria is observed due to the inability to remove urine from the kidney or dehydration with severe vomiting. With ureterolithiasis, in 80-90% of cases, macrohematuria is noted, which occurs after a painful attack. Prolonged presence of a stone in the ureter leads to the addition of leukocyturia and pyuria.
Renal colic is accompanied by a sharp deterioration in the general condition – headache, chills, weakness, dry mouth, etc. With a small stone in the ureter, renal colic can end with spontaneous discharge of the concretion. Otherwise, an acute attack of ureteral pain will definitely repeat.
Complications
The most likely complications of ureterolithiasis are:
- obstructive pyelonephritis
- hydronephrosis
- development of renal insufficiency (with bilateral ureterolithiasis or concretions of a single kidney)
In some patients with ureteral stones, the disease is aggravated by the addition of an infection – E. coli, vulgar proteus, staphylococcus, which is manifested by acute and chronic pyelonephritis, urethritis, pionephrosis, urosepsis.
Diagnostics
The clinic of renal colic with a high degree of probability makes the urologist assume the presence of ureterolithiasis. Palpation of the projection of the kidneys is extremely painful, the reaction to the symptom of pounding is sharply positive.
Urine tests with a stone in the ureter (general analysis, biochemical examination of urine, pH determination, bacteriological seeding) they can give valuable information about the presence of impurities in the urine (erythrocytes, leukocytes, protein, salts, pus), the chemical structure of stones, infectious agents, etc.
To visualize the stone in the ureter, to determine their localization, size and shape, a comprehensive X-ray, endoscopic and echographic examination is performed, including an overview X-ray of the abdominal cavity, an overview urography, excretory urography, CT of the kidneys, ureteroscopy, radioisotope diagnostics, ultrasound of the kidneys and ureters. Based on the data set, therapeutic tactics are planned for the stone in the ureter.
Treatment
Conservative and expectant tactics with a stone in the ureter are justified in the case of a small size of the concretion (up to 2-3 mm). In this case, antispasmodics, water load (more than 2 liters per day), urolitic drugs (ammi dental fruit extract, combined phytopreparations), antibiotics, exercise therapy are prescribed. With the development of renal colic, urgent measures are taken to stop it with the help of blockades, antispasmodics.
In some cases, to extract stones from the ureter, endourological intervention is resorted to – ureterolithoextraction – removal of concretions using special basket traps through the ureteroscope channel inserted into the ureter lumen. When the stone is pinched at the mouth of the ureter, its dissection is resorted to, facilitating the extraction or discharge of the concretion. After the extraction of the stone, the ureter is stented for better discharge of urine, sand and microscopic fragments of concretion.
Concretions with a diameter of more than 6 mm require fragmentation before extraction, which is achieved by ultrasound, laser or electrohydraulic lithotripsy (crushing). With a stone in the ureter, remote ureterolithotripsy or percutaneous contact ureterolithotripsy is used.
Open or laparoscopic ureterolithotomy is indicated for a stone in the ureter greater than 1 cm; infections that do not respond to antimicrobial therapy; severe, non-stop colic; non-moving concretion; obstruction of a single kidney; ineffectiveness of UVL or endourological methods.
Prevention
Prevention and prevention of recurrence of stones of ureters requires treatment of metabolic disorders, pyelonephritis, urostasis. After removing the stone and restoring the passage of urine, it is necessary to eliminate the anatomical cause of obstruction (strictures and valves of the ureters, prostate hyperplasia, etc.).
A patient with one or another form of urolithiasis is recommended diet therapy (restriction of table salt, fats), daily intake of at least 1.5-2 liters of liquid, special herbal preparations, spa rehabilitation. Carrying out a physico-chemical analysis of the composition of the removed concretion makes it possible to determine a set of measures aimed at preventing repeated stone formation.
