double ureter
Introduction
Introduction to double ureter Repetitive kidney and ureter is a kidney congenital malformation in which the affected kidney is a combination of two parts of kidney tissue, with a common capsule, but the renal pelvis and vasculature are separated. The incidence rate is 2% to 3%, which is more common in women. basic knowledge Sickness ratio: 0.0001% Susceptible people: no special people Mode of infection: non-infectious Complications: renal hypoplasia, ureteropelvic junction obstruction
Cause
Double ureteral cause
(1) Causes of the disease
1. At the 4th week of embryogenesis, the ureteral bud grows rapidly, the proximal end forms a ureter, the distal end is covered by the original renal tissue block, and develops into a renal pelvis, a renal pelvis and a collecting duct, if the distal branch of the ureter exceeds 2, the formation of repeated renal pelvis; if the branch is too early, the formation of incomplete double ureter, the ureter is Y-shaped, in addition, such as in the lower end of the middle kidney tube to produce another ureteral bud (or vice ureteral bud), it is normal The ureteral buds rise side by side, and a complete double ureteral malformation occurs.
2. Genetics Double ureter may be autosomal dominant, with incomplete penetrance, family survey parents or siblings with double ureter, the incidence rate increased from 1 in every 125 people to 8 to 9 people In one case, it was reported that environmental factors may affect the occurrence of double ureter.
(two) pathogenesis
According to the positional relationship of the repeated ureters, it can be divided into three types:
1. Incomplete double ureter, the ureter of the lower kidney is "Y" shaped into a ureter and opens in the normal position in the bladder, and the junction can be in any part of the ureter.
2. Complete double ureter Two ureters are completely separated, respectively, draining the urine of the upper and lower kidneys, and simultaneously opening in the triangle of the bladder. Generally, the ureteral opening of the lower kidney is in the normal position in the bladder, and the upper ureter is in front of the bladder. Cross the lower kidney ureter, opening to the outside of the lower ureteral opening or other parts (Weigert-meyer's law).
3. Complete double ureter with renal ureteral ectopic opening is complete double ureteral lower ureteral ureteral opening in the bladder, while upper ureteral opening is outside the bladder, males open in the posterior urethra, seminal vesicle, vas deferens, etc. Women can open in the urethra, vagina, vulva vestibule, cervix, etc.
Prevention
Double ureteral prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Double ureteral complications Complications, renal hypoplasia, ureteropelvic junction obstruction
One third of the renal parenchyma is drained by the upper collecting system. The average renal system drainer has 9.4 renal sputum, and the heavy kidney has 11.3 renal sputum. The average upper kidney has 3.7 renal sputum, and the lower kidney has 7.6. A small sputum (Privett et al., 1976), 97% of the kidneys underwent a single system drainage were normal, while 29% of those with repetitive malformations had scars and/or dilatation. If excretory bladder urethrography was performed, there were duplicates. Common regurgitation of deformities, accounting for 42%, and only 12% of people without repeat deformity, the lower kidney often has water due to concurrent reflux, but also has lower renal pelvic ureteral junction obstruction, and other malformations There were also many opportunities. In the Nation group, 27 patients (12%) had other urinary malformations, including renal hypoplasia or renal dysplasia and various ureteral abnormalities. Among them, 4 had ureteral ectopic (occupy of ureteral ureter) 3%), 129 of the 342 double ureters in the Campbell group had urinary malformations, 63 had no urinary malformations, the urinary malformations were similar to the Nation group, and 22 had contralateral renal malformations.
Symptom
Double ureteral symptoms Common symptoms Urinary tract infection Urinary frequency Urinary urgency Incontinence ejaculation
Clinical symptoms vary greatly depending on gender. Due to embryological differences, male ectopic ureters are more likely to open in the bladder neck, prostate, seminal vesicle, epididymis and vas deferens, all located above the external urinary sphincter, so the symptoms of urinary tract infection are generally Such as constipation, post-pubic pain, ejaculation discomfort, etc., can also be accompanied by urgency, frequent urination, occasionally infertility treatment but rare urinary incontinence, in terms of women, the most common opening is the vestibule, can also be located in the upper vagina, uterus, ovary Because the ectopic opening is mostly located at the distal end of the external urethral sphincter, it is often characterized by persistent urinary incontinence after normal urination. Another characteristic of female ectopic ureteral opening is persistent vaginal discharge. Most female patients have acute and chronic urinary tract. Urinary tract infection, a small number of pyelonephritis and ureteral hydrops, occasionally a patient with abdominal mass.
Examine
Double ureter examination
Diagnosis mainly relies on intravenous urography and cystoscopy. It is recommended to use high-dose intravenous infusion of urography. Pediatrics can directly push the contrast agent into the vein with a syringe to control the injection time. Large-dose intravenous drip can be used without abdominal pressure. Belt, more satisfactory for showing the whole process of ureter.
If the function of the upper kidney segment of the kidney is present, the whole appearance of the deformity can be clearly seen on the X-ray angiography. The higher the convergence point of the two ureters, the clearer the display; if the convergence point is too low, the display is often poor, sometimes it is indistinguishable. The double ureter is complete or incomplete. If the function of the renal segment is poor, it should be used for continuous filming. Even if it needs to be continued for 24 hours, if the renal function is almost completely lost, the kidney should be carefully observed and analyzed. The morphology of the renal pelvis and renal pelvis generally shows that the upper renal pelvis is absent, and the inclination of the renal pelvis is increased, like a drooping flower, and away from the edge of the vertebral body; the lower ureter is often dilated and twisted by the ureteral tract of the upper kidney segment. Lateral or medial, sometimes "S"-shaped curved decline, in the case of non-function in the upper kidney segment, the lower kidney segment development is much smaller than the normal kidney (contralateral), sometimes misdiagnosed as small renal malformation or kidney development Poor, ureter-ureteral reflux is sometimes seen on the continuous film.
If more than two ureteral openings are found during cystoscopy, a diagnosis of double ureteral malformation can be established. If a ureteral catheter can be inserted for retrograde angiography, the diagnosis is more clear. Of course, there are only 2 ureteral openings in the bladder triangle. Double ureteral malformation can not be completely ruled out, because the incomplete double ureteral malformation, the ureteral opening can be normal; in addition, there may be a ureteral opening that is ectopic, but may not necessarily open the bladder, cystography sometimes finds that one of the double ureters has a counter Flow phenomenon, combined with intravenous urography, can explain the problem.
Diagnosis
Double ureter diagnosis
diagnosis
About 60% of cases have no obvious symptoms. Although urinary tract infection is not a unique feature of double ureter, cases of recurrent urinary tract infection should consider the possibility of a double ureter, combined with intravenous urography and cystoscopy. Confirmed diagnosis.
Differential diagnosis
Additional kidney
It is the third kidney that is independent or is connected to the normal kidney by loose tissue. It is smaller than the normal kidney, mostly between the two normal kidneys, in front of the spine or slightly on one side. The attached kidney has its own independent collecting system, blood supply. And the capsule, completely dissected from the normal kidney, therefore, by urography, B-ultrasound and CT examination are easier to identify with repeated kidneys.
2. Kidney compensatory increase
When one side of the kidney is missing, underdeveloped or functionally impaired, the contralateral kidney can be compensated for an increase, but urography is found to have only one side of the collection system and the ureter, and contralateral renal lesions can be found.
3. Simple renal cyst
In particular, the superior cyst of the kidney needs to be differentiated from the recurrent renal water. B-ultrasound shows that the renal cyst is a circular anechoic dark area in the renal parenchyma. IVU shows that there is only one set system and ureter, and the renal pelvis and renal pelvis are under pressure. Deformation.
