Ureteral stones

Introduction to ureteral stones The vast majority of ureteral stones are derived from the kidneys, including kidney stones or stones falling after extracorporeal shock waves. Since urinary salt crystals are easier to discharge into the bladder with urine, primary ureteral stones are rare. In the presence of ureteral strictures, diverticulum, foreign bodies and other predisposing factors, urine retention and infection can promote ureteral stones. Most of the ureteral stones are single, the incidence on the left and right sides is roughly similar, and bilateral ureteral stones account for about 2 to 6%. Clinically seen in young adults, the incidence rate is the highest in 20 to 40 years old, the ratio of male to female is 4.5:1, and the stones are located in the lower part of the ureter, accounting for 50-60%. Urine flow above the ureteral calculi can cause obstruction and dilated water, and endanger the kidney. In severe cases, renal function can be gradually lost. basic knowledge The proportion of the disease: the probability of the population is 0.2% Susceptible people: no special people Mode of infection: non-infectious Complications: hydronephrosis, urinary tract infection, renal insufficiency, renal colic

Causes of ureteral stones

Ureteral stenosis (15%):

Due to the narrowing of the ureteral lumen and the physiological stenosis, small stones can easily stay in these stenotic areas, causing incarceration. Ureteral calculi rarely cause complete obstruction. Because the stones are usually irregular jujube nucleus, urine Generally, it can pass from around the stone. Depending on the height, the length of the adult ureter is about 22~30cm. The diameter of the ureter is different. There are three physiological stenosis in the anatomy: the inner diameter of the ureteropelvic junction is about 2mm; the ureter spans the iliac vessels. The inner diameter is about 4mm; the inner diameter of the ureteral bladder junction is about 3~4mm. The narrowest part of the ureter is the part that enters the bladder through the submucosal passage of the bladder, that is, the ureteral bladder wall segment. The ureter can be divided into the abdomen and pelvis, and the abdomen refers to the renal pelvis. To the iliac vessels: the pelvic part refers to the iliac vessels to the bladder. The above three stenotic parts are the urinary calculi in the descending process, the most likely to occur in the incarceration of the obstruction, but in general, the stones often stay in the lower part of the ureter 5cm Within the range, partial obstruction of the stone can cause ureteral dilatation of the renal pelvis and the proximal end of the stone, if it is discharged in a short time , will not cause any damage, if the residence time is too long, in the early expansion of the ureter smooth muscle compensatory hyperplasia and hypertrophy, the ureteral cavity gradually expands, stretches, twists, thinning the wall; later lesions will gradually affect the kidneys, resulting in Renal stasis and hydronephrosis, if the time is too long, will cause irreversible damage to kidney function as with complete obstruction.

Environmental factors (25%):

The causes of ureteral stones are geographical environment and climate: the occurrence of urolithiasis has a certain regionality. The incidence of urolithiasis in mountainous, desert, tropical and subtropical regions is high, which is mainly related to environmental factors such as eating habits, temperature and humidity.

Dietary factors (25%):

The causes of ureteral stones are diet and nutrition: poor diet is an important cause of ureteral calculi. There is information that the intake of animal protein and refined sugar in the diet can increase the risk of formation of upper urinary tract stones. Others such as fat, sputum, oxalic acid, calcium, phosphorus, trace elements, vitamins, etc. all affect the formation of urinary stones. Good nutritional status, when the animal protein intake is too much, it is easy to form kidney stones.

Water intake (10%):

The cause of ureteral calculi is water intake: any factor that destabilizes the intake of water and the amount of loss, such as excessive sweating, will increase the excess of calcium and salt in the urine, which is conducive to the formation of urinary stones. Conversely, a large amount of drinking water dilutes the urine, which can reduce the formation of crystals in the urine.

Disease factor (10%):

The cause of ureteral stones is disease: some ureteral stones are associated with hereditary diseases, such as cystineuria, familial jaundice and so on.

Pathogenesis

Most of the ureteral stones are derived from the primary kidney stones, which fall into the ureter due to gravity and turbidity of the urinary tract. Therefore, the components of the ureteral stones are the same as those of the kidney stones, mainly oxalate stones, followed by uric acid stones, primary Urinary calculi are rare, often secondary to some ureteral diseases, such as ureteral polyps, tumors, cysts, stenosis, diverticulum and giant ureteral disease, due to urinary stasis in the ureter, the formation of stones in the accumulation of urine.

After the formation of ureteral stones, various secondary damages will occur to the ureter. The degree of injury depends on the size, shape, location, and medical history of the stones. The main secondary lesions include urinary tract obstruction, secondary infection and epithelial injury.

Ureteral calculus prevention

1. Develop the habit of drinking more water

Drinking more water can dilute the urine, reduce the crystal concentration in the urine, flush the urinary tract, help prevent the formation of stones and promote the discharge of urinary stones. Generally, adults drink more than 2000 ml of boiling water or magnetized water per day, which has certain significance for preventing stones. Usually you can soak some money grass, dandelion, dish, grass, honeysuckle drink, can effectively inhibit bacteria and pain, diuretic Tonglin, dissolved stone, and can expand the urinary system to prevent recurrence after stone discharge.

2, relieve the urinary tract obstruction

Active treatment of urethral stricture, benign prostatic hyperplasia, etc., to relieve urinary tract obstruction.

3. Active treatment of urinary tract infections

4, long-term bedridden patients, should encourage and help their activities, in order to reduce bone decalcification, improve urine flow.

5, adjust the urine pH

According to the composition of urinary stones, adjusting the pH of urine can prevent the recurrence of uroliths, such as urate and oxalate stones formed in acidic urine, and phosphate and carbonate stones are formed in alkaline urine.

6, prevention and treatment of metabolic diseases, such as hyperthyroidism should be treated surgically.

7, diet regulation and drug prevention

According to the composition of the stone, the diet should be adjusted appropriately. For example, patients with oxalate stones should eat less oxalic acid-rich foods such as potatoes and spinach. Oral vitamin B6 can reduce the discharge of oxalate in urine. Oral magnesium oxide can be used. Increase the solubility of oxalate in urine. Phosphate stones patients should be low-phosphorus low-calcium diet, oral ammonium chloride acidification of urine, is conducive to the dissolution of phosphate. Patients with urate stones should eat foods rich in sputum, such as liver, kidney and beans, oral citrate mixture or sodium bicarbonate, alkalinize urine, so that the urine pH is maintained above 6.5.

Ureteral calculi complications Complications, hydronephrosis, urinary tract infection, renal insufficiency, renal colic

Common complications of ureteral calculi are obstruction and infection. The former can cause hydronephrosis, and there is a mass in the upper abdomen or waist. The latter is a symptom of urinary tract infection.

Symptoms of ureteral calculi Common symptoms Ureteral pain Urinary urgency High oxalic acid Snoring Breathing Kidney-induced renal failure Cold sweaty pale nausea diarrhea

The symptoms of ureteral calculi and kidney stones are basically the same. The ureteral colic caused by the upper ureteral calculi is characterized by one side of low back pain and microscopic hematuria. The pain is mostly colic and can be radiated to the ipsilateral lower abdomen, testis or labia, hematuria. Mild, most of them only have microscopic hematuria, but the hematuria is aggravated after the onset of pain. About half of the patients have gross hematuria. Colic with nausea and vomiting, cold sweat, pale, abdominal distension, shortness of breath, etc., ureteral bladder wall Segment stones can cause frequent urination, urgency, dysuria and ipsilateral hydronephrosis and infection. Bilateral ureteral stones can cause anuria. If there is hydronephrosis and infection, physical examination may touch the kidneys and may have tenderness, sometimes along the ureter. There is tenderness in the area, and rectal or vaginal examination may touch the lower end of the ureter.

Ureteral calculi examination

Laboratory inspection

1. Serum examination: calcium, phosphorus, uric acid, plasma protein, blood carbon dioxide binding, potassium, sodium, chlorine, creatinine, etc.

2. Urine check

(1) Urine routine: protein negative or trace, pH varies with stone composition, red blood cells can be seen by microscopy. If infected, pus cells can be seen, and sometimes crystals and crystal agglomerates can be seen in urine.

(2) Urine culture and bacterial drug sensitivity test.

(3) 24-hour urine analysis: determination of calcium, phosphorus, uric acid, oxalic acid, cystine, magnesium, sodium, chloride, citric acid, creatinine and the like.

3. Analysis of stone composition.

4. Special metabolic tests: such as urine examination of renal tubular acidosis, metabolic examination of hyperparathyroidism, laboratory examination of hypercalciuria.

Film degree exam:

1. Urinary flat and tomogram

The plain film must include the entire urinary system. More than 90% of the stones are developed on the X-ray film. The depth of the development is related to the chemical composition, size and thickness of the stones. The kidney stones of different compositions are arranged in order of the strength of the development to calcium oxalate. , calcium phosphate and ammonium magnesium phosphate, cystine and calcium urate, pure uric acid stones are not developed, the degree of development of stones on the flat sheet is affected by many factors, such as small stones, intestinal gas, obese patients, often develop Not satisfied.

The tomographic X-ray film can produce a clearer flat film at different levels, and can also be displayed on smaller stones. The radiopaque shadows displayed on the flat film should be associated with abdominal lymph node calcification, venous stones, bone islands, kidney tuberculosis and Identification of calcification phase of renal tumors.

2. Excretory urography

It can show changes in renal structure and function caused by stones, and whether there are local factors causing stones. Negative stones appear as filling defects in the developed renal pelvis, similar to space-occupying changes, poor renal function, and poor development. High-dose excretory urography.

3.B type ultrasound examination

The stone is characterized by special sound and shadow. It can be found on small stones and X-ray stones that cannot be displayed on the flat film. It can understand the influence of stone obstruction on the kidney structure.

4. Cystoscopy and retrograde pyelography

Cystoscopy is not used as a routine examination. It is suitable for the diagnosis of excretory urography, such as intravenous pyelography (IVP), poor renal development or poor development. Considering the possibility of negative stones, the ureter is removed under the stones. Obstruction and stenosis.

5. CT uric acid stones that are not developed by X-ray, CT can be diagnosed.

6. Ureteroscopy

KUB did not show stones and IVP showed a filling defect and could not be diagnosed. This examination can confirm the diagnosis.

Diagnosis and diagnosis of ureteral calculi

diagnosis

According to the typical clinical manifestations, combined with laboratory examination and B-ultrasound, X-ray examination, most of the upper urinary tract stones are not difficult to diagnose, but should not be satisfied with this, should also understand the location, size, number and presence or absence of obstruction and infection of the stone The condition of impaired renal function, the composition of the stone and the primary cause of the formation of stones, understanding the composition of the stone and the cause of the formation of stones, is conducive to taking measures to prevent the recurrence of stones.

In the medical history, attention should be paid to the presence or absence of the primary cause and influencing factors of the formation of stones. The following points are worth highlighting.

1. Diet: High protein diet intake will increase urinary calcium, oxalic acid, uric acid secretion, lower urine pH and reduce uric acid secretion, long-term drinking milk can cause hypercalciuria, high-dose vitamin C use Can cause high oxalic aciduria.

2. Drugs: The use of corticosteroids, lead-containing antacid preparations, medullary diuretics, vitamin D can cause hypercalciuria, leukemia patients with chemotherapy drugs can cause uric acid stones.

3. Infection: Urinary tract infections, especially infections with urease-producing bacteria, can cause infectious stones. About 30% of patients with calcium oxalate stones have a history of infection with Escherichia coli.

4. Activity level: Brake syndrome such as long-term bed rest after paraplegia can cause bone decalcification and easily form stones.

5. Systemic diseases: primary hyperparathyroidism, gout, sarcoidosis, distal renal tubular acidosis can cause kidney stones.

6. Inheritance: Distal renal tubular acidosis, cystineuria is a hereditary disease, the possibility of multiple members of the family suffering from kidney stones can be increased by 4 times.

7. Anatomy: Obstruction of the urinary system such as congenital ureteropelvic junction stenosis, hoof iron, medullary sponge kidney, benign prostatic hyperplasia, urethral stricture can produce kidney stones.

8. History of surgery: History of abdominal surgery, such as short bowel syndrome caused by bowel resection and postoperative diarrhea, can cause hypercalciuria.

Differential diagnosis

Most ureteral calculi are easy to diagnose. Clinical misdiagnosis is often related to incorrect examination, not timely or inexperienced factors. Patients with acute abdomen such as cholecystitis, cholelithiasis, acute appendicitis, ulcer disease, pancreatitis, intestinal obstruction, Ovarian cysts are reversed, and the pain caused by ectopic pregnancy is easily confused with the pain of ureteral stones. However, the pain of biliary tract disease is mostly in the upper abdomen and radiates to the back, while the pain of ureteral stones is in the rib angle and radiates to the ureteral approach. At the onset of biliary tract disease, right upper quadrant tenderness, muscle tension, rebound tenderness, Murphys sign, slightly elevated white blood cells, acute appendicitis pain and physical examination positive signs are confined to the right lower abdomen, and may be accompanied by chills, fever, diarrhea Such systemic symptoms, urine routines are more normal, red blood cells can also occur, ovarian cyst pedicle torsion and ectopic pregnancy general urine test is normal, the lesion is confined to the lower abdomen, if necessary, pregnancy urine test and pelvic puncture can be used to determine the presence or absence of bleeding to help differential diagnosis.

The shadow of the intra-abdominal lymph node calcification varies greatly at different times. The position of the shadow of the ureteral calculus is relatively fixed. The lateral calcification of the lymph nodes and the cholelithiasis are located in front of the vertebral body, while the ureteral calculi are located behind the anterior vertebral body.

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