Ureterovesical Obstruction Research Articles

Hydronephrosis in Renal Ectopia: Incidence, Etiology and Significance

The incidence, cause and significance of hydronephrosis in patients with renal ectopia are unknown. Therefore, we conducted a retrospective review of 77 patients with 82 ectopic kidneys. Of 82 kidneys 46 (56%) had hydronephrosis. Dilatation of the renal pelvis was the result of primary ureteropelvic or ureterovesical obstruction in 52%, grade 3, 4 or 5 vesicoureteral reflux in 26% and extrarenal collecting systems with malrotation that produced apparent ureteropelvic junction obstruction in 22%. Surgery was performed in 41 patients, including primary nephrectomy in 18, ureteral reimplantation in 14 and ureteropelvic junction repair in 8. Hydronephrosis was present in 15 of 58 contralateral nonectopic kidneys, and 11 required surgery mostly for vesicoureteral reflux. Solitary ectopic kidneys with no associated obstruction or reflux demonstrated normal renal function. Our data indicate that the prognosis in renal ectopia relates directly to the associated urological disease and timely surgical intervention, not to ectopia alone.

Dysfunctional voiding syndromes and vesicoureteral reflux.

Micturition disorders simulating neurogenic bladder disease have been loosely termed "dysfunctional voiding". No underlying neuropathy can be found. A variety of voiding disturbances have been identified since the early 1970s, each with its own characteristics and clinical relevance. We have classified voiding dysfunctions into mild, moderate and severe, according to their potential impact on the upper tracts. Bladder instability, the Hinman syndrome and the Ochoa syndrome are the only dysfunctional voiding syndromes that are associated with reflux or ureterovesical obstruction. Each syndrome is briefly described.

Ureteral Reimplantation in Infants

Between 1984 and 1990, 30 infants (46 ureters) 8 weeks to 6 months old (mean age 4 months) underwent ureteral reimplantation. Weight at operation ranged from 4.9 to 9.5kg. (mean 6.9). Underlying abnormalities were primary vesicoureteral reflux (28 ureters), primary ureterovesical junction obstruction (11), ectopic ureterocele (4) and ectopic ureter (3). Patients with reflux underwent surgery because of high grade reflux (grade IV or V) or breakthrough infection. Infants with primary ureterovesical junction obstruction underwent obstructive diethylenetriaminepentaacetic acid diuretic renograms. Reimplantations performed included 44 Glenn-Anderson advancements, 1 Cohen cross-trigonal advancement and 1 Politano-Leadbetter procedure. Of the ureters 30 (65%) were tapered intravesically. Ureteral stents were used in all instances. Transient ureteral obstruction developed in 2 children following stent removal and 1 required temporary percutaneous nephrostomy drainage. No permanent ureterovesical obstruction was noted in any patient.Followup at 18 months revealed no postoperative reflux in 43 of 46 ureters (93%). One infant required repeat reimplantation to correct a vesicoureteral fistula and the remaining 2 patients (2 ureters) with low grade reflux (grade I and II) are being observed. Surgery was successful in 27 of 30 tapered ureters (90%) and in all 16 of the nontapered ureters (100%). While the majority of infants with ureterovesical junction abnormalities may be observed, some may require surgery. Reimplantation, when necessary in this age group, can be performed with a high degree of success and diverting procedures such as vesicostomy or ureterostomy can be avoided.

Ureteral Bladder Augmentation

Virtually all segments of the gastrointestinal tract have been used successfully in augmentation cystoplasty. The complications inherent in enterocystoplasty are well described. Megaureters subtending effete kidneys (poorly or nonfunctioning) provide a novel and excellent source of augmentation material with urothelium and muscular backing, free of the electrolyte and acid base disturbances, and mucus production that plague enterocystoplasty. Augmentation cystoplasty using detubularized, reconfigured, otherwise disposable megaureter, with or without ipsilateral total or partial nephrectomy, was performed in 16 patients (mean age 8.8 years, range 1 to 25) with inadequate and dysfunctional bladders.Postoperative followup varied between 8 and 38 months (mean 22). The overall renal function and radiographic appearance of the remaining upper tracts have remained stable or improved in all patients. Of the 16 patients 15 require intermittent catheterization and 1 voids spontaneously. Ten patients are continent day and night, 5 have improved continence (4 damp at night and 1 stress incontinence) and 1 has failed to gain continence despite good capacity and compliance. Complete postoperative urodynamic evaluations in 12 of 13 patients show good capacity, low pressure bladders with no instability. Complications occurred in 5 patients, including transient urine extravasation in 2, contralateral ureterovesical obstruction in 2 and Mitrofanoff stomal stenosis in 1. Augmentation ureterocystoplasty combines the benefits common to all enterocystoplasties without adding any of the untoward complications or risks associated with nonurothelial augmentations.

Renal hypoplasia and postnatally acquired cortical loss in children with vesicoureteral reflux.

We reviewed histologically 86 nephrectomy specimens from patients with vesicoureteral reflux (with or without ureterovesical obstruction) to investigate the relationship between coexisting hypoplasia and postnatally acquired cortical damage. Hypoplasia was assessed independently of the acquired cortical loss using medullary ray glomerular counting. Severe hypoplasia (glomerular number < 25% of normal) was detected in 47 of 86 patients. These patients underwent nephrectomy at a significantly younger age than those with minimal or no hypoplasia (P < 0.01). There was no significant relationship between the severity of hypoplasia and the presence or absence of obstruction. Severe acquired cortical loss was found in 68 of 86 patients. There was no significant association between the severity of cortical loss and the presence or absence of obstruction, age at nephrectomy or degree of coexisting hypoplasia. The findings suggest a strong association of hypoplasia and vesicoureteral reflux. Therefore, early postnatal presentation with minimal renal function need not necessarily reflect a failure of management but rather a pre-existing limitation of renal capacity. Furthermore, in a significant proportion of fetuses with ultrasonographic evidence of urinary tract abnormality, renal pathology may be present prior to the time at which in utero surgical intervention may be considered.

Percutaneous Balloon Dilation of Ureteral Strictures after Failed Surgical Repair in Children

We attempted treatment of long-standing strictures of ureterovesical or ureterosigmoid anastomosis in 6 children by percutaneous balloon dilation. The 4 girls and 2 boys were between 2 and 19 years old (mean age 9 years) at the time of dilation. Obstruction occurred at the ureterosigmoid anastomosis in 3 patients and at the ureterovesical junction in 3. Obstruction was confirmed by diuresis renography, antegrade pyelography and pressure perfusion studies. An attempt at dilation was unsuccessful for 1 patient. For the remaining 5 patients the ureter has remained patent for a followup period of 7 to 18 months (mean 12 months).Percutaneous balloon dilation of established ureterointestinal and ureterovesical obstruction after failed surgical repair can be successful. The hospital stay is reduced and major surgery with its accompanying morbidity is avoided. If balloon dilation is unsuccessful, surgical repair remains an option. Balloon dilation should be seriously considered as an initial form of treatment in this group of patients.

Alternatives in the Management of Posterior Urethral Valves

The child with posterior urethral valves poses a continuing treatment dilemma because congenital infravesical obstruction may result in long-standing dysfunction of all segments of the urinary tract. Relief of the obstruction may not return bladder pressure to normal or completely resolve abnormalities of ureteral drainage. Dysplastic renal parenchyma cannot recover. Four issues affect the identification of those children who will benefit from therapy beyond transurethral valve destruction: the concept of transitional nephrology, the possibility of coexisting ureterovesical obstruction, the valve bladder syndrome, and prenatal urology.

Urolithiasis in Childhood Acute Leukemia and Nonhodgkin’s Lymphoma

Ureteral calculi were found in 5 children who were receiving or had recently completed remission induction therapy for acute leukemia or lymphoma. All 5 patients had abdominal or back pain and 3 had gross hematuria. The diagnosis of urolithiasis was suggested by excretory urograms that showed obstructive uropathy (4 patients) and by computerized tomography scans that demonstrated ureterovesical obstruction (1 patient with acute renal failure and anuria). With a single exception the calculi were not associated with urinary tract infections. Chemical analyses in the 2 patients tested indicated that the stones were composed of calcium, in contrast to the uric acid and xanthine compositions of stones in earlier studies of patients with leukemia or lymphoma. Factors that might have predisposed our patients to calculi formation include corticosteroid therapy, immobilization owing to bed rest and urinary alkalization. Other possible contributing factors were urinary stasis (2 patients) and a familial tendency for renal calculi to develop (2). There was no evidence of idiopathic hypercalciuria in either patient tested. Prompt detection of urolithiasis in children undergoing induction chemotherapy for a malignant disease may avoid potentially serious consequences from urinary tract obstruction.

Ureterovesical obstruction and megaloureter: diagnosis by real-time US.

Forty infants and children were accurately diagnosed with real-time ultrasound (US) as having megaloureter secondary to ureterovesical junction (UVJ) obstruction by an adynamic, distal ureteral segment. Characteristic US findings were dilatation of the distal ureter, often disproportionate to the appearance of the upper collecting system; lower ureteral hyperperistalsis; and a sharply tapered, incurving, distal adynamic segment, 1-3 cm long. Real-time US, used routinely in preliminary evaluation of the urinary tract in children, can facilitate early diagnosis of UVJ obstruction and thus prevent significant loss of renal function.

Diuretic Radionuclide Localization of Upper Urinary Tract Obstruction

In 59 children with proved upper urinary tract obstruction diuretic radionuclide ureteral scans provided an accurate assessment of ureteral dilatation sufficient to distinguish ureteropelvic from ureterovesical obstruction. As a result, this test may be used instead of more invasive studies, such as retrograde or antegrade pyelography, to determine the site of obstruction in many cases of hydronephrosis.

Early Postoperative Assessment of the Functional Patency of Ureterovesical Junction following Ureteroneocystostomy

We studied 37 children soon after ureteroneocystostomy using diuretic radionuclide urography to assess the patency of the ureterovesical junction. Postoperative obstruction was excluded correctly in 90 per cent of the patients. Transient ureterovesical obstruction occurred in 5 patients, identification of which was useful in assigning risk and in guiding followup studies. Because it is a safe, non-invasive and relatively low radiation test the diuretic radionuclide urogram proves to be an attractive alternative to the excretory urogram in the early and late followup of patients undergoing a ureterovesical junction operation.

Fate of Vesicoureteral Reflux in Children with Neuropathic Bladders Managed by Intermittent Catheterization

During the last 9 years 49 children with vesicoureteral reflux and neurogenic bladder dysfunction were treated with intermittent catheterization. Reflux spontaneously abated in 22 of 72 ureters (31 per cent). Reflux has been followed non-operatively in 17 ureters without renal deterioration. Reimplantation was successful in 24 ureters. In no instance was there ureterovesical obstruction or recurrence of the reflux and in none of the 12 unilateral reimplantations did contralateral reflux develop. Our experience suggests that children with reflux may be managed safely by intermittent catheterization, and that ureteroneocystostomy is reliable and effective in neurogenic bladder disease provided that bladder dysfunction is controlled.

Percutaneous approach to the renal pelvis: combined use of ultrasonography and fluoroscopy.

The percutaneous approach to the renal pelvis provides access for antegrade urography, percutaneous nephrostomy, or endourologic manipulation. Having performed 31 successful procedures, including the percutaneous placement of double-pigtail ureteral stents for ureterovesical obstruction, we advocate the combined use of ultrasonography and fluoroscopy to achieve optimal results.

Ureteral reconstruction in renal transplantation

The complications associated with ureteral reconstruction in renal transplantation produce significant morbidity and mortality rates. We have evolved a combined intravesical-extravesical nonstented ureteroneocystostomy and have used it in 100 consecutive transplants, 50 of which were in high-risk diabetic recipients. No instances of urinary extravasation, fistula formation, disruption of the ureterovesical anastomosis, ureteral sloughing, or ureterovesical obstruction have occurred in this series. The lack of urologic complications utilizing this technique offers reduced morbidity and mortality to transplant recipients.

Extravesical Reconstruction for Ureterovesical Obstructions in Childhood

The blind empirical practice of ureteral reimplantation for all types of ureterovesical obstruction is founded on entirely speculative concepts of the nature of the obstruction. A significant proportion of ureterovesical obstructions are caused by a tilt-valve type of abnormality of the distal ureter with a normal juxtavesical segment. These can be corrected rationally by an extravesical ureteroureteroplasty. This procedure was done between 1968 and 1975 to relieve obstruction of 9 ureters in 8 children. The pathological anatomy found in these cases is defined and the technique of operative recognition and reconstruction is described. With adequate operative recognition and appropriate case selection relief of obstruction was achieved and maintained in 7 of the 9 ureters.

EXSTROPHY OF THE BLADDER

Exstrophy of the bladder is the most common example of a spectrum of related anomalies. The pelvic skeletal changes in all of these disorders may vary in degree but are similar in type. The kidneys and urinary collecting systems are almost always normal in patients with untreated exstrophy, and the usual “hurley” appearance of the lower ureters should be regarded as a physiologically normal variant, not as indicative of significant ureterovesical obstruction. There are three main types of surgical therapy. Primary closure of the bladder remains the ideal to be aimed for. Unfortunately, diminished capacity of the bladder and incontinence are major problems, and there is a risk of malignancy of the bladder. Ureterosigmoidostomy and cystectomy constitute the second mode of therapy, and the one most widely accepted. Complications which must be carefully sought for by the radiologist include sigmoid-ureteral reflux and ureteric obstruction. The latter may be due to calculus, stricture, inflammation, polyp, or malignancy at the site of the ureterosigmoid anastomosis. Finally, urinary diversion by an ileal or colonic conduit may be undertaken if ureterosigmoidostomies are not possible or fail. Regardless of the type of surgical management, periodic (e.g., annual) intravenous urography is mandatory throughout the patient's life. Following ureterosigmoidostomies renal destruction and colonic malignancy are the two major threats to life. Radiology plays an extremely important role in their detection.

The Surgical Approach to Urological Complications in Renal Allotransplant Recipients

Urinary extravasation or ureteral obstruction occurred in 22 patients who received 30 transplants in a series of 290 renal transplants. This incidence represents 10.3 per cent of the entire transplant experience at The Johns Hopkins Hospital and Baltimore City Hospitals from 1968 to the present time. Ureteroneocystostomy was used as the primary form of urinary tract reconstruction in all but 1 patient who had urinary complications. These 22 patients received 30 renal transplants: 6 from living related donors and 24 from cadaver sources. There were 15 instances of urinary extravasation and 14 instances of obstruction. All but 2 fistulas were diagnosed within 30 days of the original transplant. Obstruction occurred later, with 4 cases of ureterovesical obstruction being diagnosed 3 to 5 years after the transplant procedure. The ureterovesical junction or bladder was the site of complication in 17 of the 29 instances. Surgical management in these cases was highly individualized, with successful outcomes more commonly attained in those cases characterized by obstruction. Ureteral stents were used in all but 1 secondary procedure involving the ureter and these stents were not associated with an increased incidence of urinary tract infection. Death directly related to the urological complications occurred in 2 cases, 5 patients underwent transplant nephrectomy and 2 patients died of rejection and infection more than 6 months after the urinary fistulas were successfully managed. From the original series, there are 15 of the 22 patients who have stable renal function after secondary or tertiary urological procedures on the transplanted kidney. Four patients underwent surgical correction of hydronephrosis associated with infection or diminishing renal function more than 3 years after the transplantation and 3 of these had good results.

Investigating Wide Ureters with Ureteral Pressure Flow Studies

A perfusion study is described and its usefulness in the diagnosis of ureterovesical obstruction is discussed. The study includes 31 children with either primary or secondary non-refluxing wide ureters or ureters that had been reimplanted previously.

A SYNDROME OF ECTRODACTYLY, ECTODERMAL DYSPLASIA, CLEFT LIP AND PALATE, PARTIAL ANODONTIA AND UROGENITAL ABNORMALITIES

Three of four siblings born to nonconsanguineous unaffected parents had various manifestations of a multiple malformation syndrome. All three had hypohidrotic ectodermal dysplasia and partial anodontia. A 20 year old white woman had cleft lip and palate, ectrodactyly and syndactyly of the hands and mild to moderate conductive hearing loss. A 13 year old boy had cleft lip and palate, syndactyly, moderate hearing loss and an ilial bladder. He had had a hydrocele and urethral obstruction. A 12 year old girl had absence of the labia minora. Absence of the right kidney and ureterovesical obstruction on the left were detected roentgenographically. The obstruction was corrected surgically. The disorder in this family is similar to that described previously by Rosselli and Gulienetti and by Bowen and Armstrong. It would appear to be of autosomal recessive inheritance.

Multiple fibrous polyps of ureter

A case is presented of multiple fibrous polyps of the upper ureter associated with ureterovesical obstruction in an eleven-year-old girl. Local excision of the polyps was done with reimplantation of the ureter in the bladder. Follow-up for forty four months showed a good functional result with no evidence of recurrent disease.