Management of ureteropelvic obstruction in the first year of life

Does delayed operation for pediatric ureteropelvic junction obstruction cause histopathological changes?

PURPOSE

We studied histopathological changes in kidneys with demonstrable ureteropelvic junction obstruction in relation to patient age, differential renal function and urinary tract infection.

MATERIALS AND METHODS

Renal biopsy was performed in 42 children (44 kidneys) with a mean age of 3 years 6 months who underwent open pyeloplasty due to ureteropelvic junction obstruction. Each specimen was examined for reversible inflammatory cell infiltration and irreversible change, including interstitial fibrosis, arteriolar thickening and glomerular sclerosis. Each pathological finding was scored 0 to 3 in increasing grades of severity, and correlated with patient age, differential renal function and history of urinary tract infection.

RESULTS

Of the 44 kidneys 20 (45%) had irreversible change. Correlation study revealed no association between patient age and histological findings, and there was no statistically significant difference in any histopathological category regardless of age. Differential renal function correlated with inflammatory cell infiltration and interstitial fibrosis. There were significantly worse histopathology scores in all categories when differential renal function was less than 30 versus 40% or greater. Interstitial fibrosis was significantly worse in the 30 to 40% group than in the greater than 40% group. The histopathological score of interstitial fibrosis was significantly higher in patients with than without urinary tract infection.

CONCLUSIONS

Early correction in infants with ureteropelvic junction obstruction may not be necessary when initial differential renal function is greater than 40%. However, any decrease in differential renal function or recurrent urinary tract infections despite antibiotic prophylaxis warrant surgical correction of obstruction.

Evolution in the management of infant pyeloplasty

Improving diagnostic modalities, evolving concepts regarding perinatal renal physiology, and advances in surgical technique have contributed to an evolution in the management of infant pyeloplasties. Currently, the majority of patients present with a prenatal diagnosis of ureteropelvic junction obstruction and do not require surgical intervention prior to 4 weeks of age. Postnatal ultrasound, voiding cystourethrography, and nuclear renography complete the diagnostic evaluation, with intravenous urography and retrograde pyelography being unnecessary in the majority of infants. A decreasing incidence of complications and a shortening of hospital stay has been documented. We presently prefer a dismembered, nonintubated technique performed through a dorsal lumbotomy approach.

Outcome of hydronephrosis diagnosed antenatally

We evaluated 23 neonates with prenatally diagnosed dilatation of the renal pelvis involving 33 renal units. The dilatation was graded from 0 to 4 by ultrasonography. Diuresis renography was used to evaluate differential renal function. The patterns of the excretory curve following administration of furosemide were analyzed. Antegrade pyelography and pressure flow studies were done in selected patients. The mean follow-up was 34 weeks. The single most important prognostic indicator in this group of patients was the degree of dilatation on ultrasonography. Six of 7 renal units with grade I hydronephrosis improved and 1 remained stable on follow-up. Four of the 12 renal units with grade II hydronephrosis improved spontaneously; 1 remained stable. Three of 11 renal units with grade III hydronephrosis either improved or remained stable. The measurement of differential renal functions on DTPA renography did not correlate well with the degree of dilatation when renal size and parenchymal thickness were adequate. The excretory curves after lasix administration were not helpful to determine treatment in the neonatal period. Seventeen renal units (7 grade II, 9 grade III, 1 grade IV) were treated surgically due to persistent dilatation, evidence of obstruction on either DTPA renography or the Whitaker test, or because of impaired renal function. Sixteen of the 33 renal units diagnosed prenatally improved with observation. Of all the parameters studied only the degree of dilatation on ultrasonography correlated well with the prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Endopyelotomy for secondary ureteropelvic junction obstruction in children

Percutaneous endopyelotomy has been shown to be successful in treating ureteropelvic junction obstruction in adults. Little data have been published regarding this procedure in children. We describe 4 patients 6.5 weeks to 5.5 years old who underwent percutaneous endopyelotomy to treat ureteropelvic junction obstruction following failed open dismembered pyeloplasty. Preoperative obstruction was demonstrated by a nephrostogram, diuretic renogram and/or ultrasonography. Percutaneous endopyelotomy was successful in relieving the obstruction in all 4 patients, although 2 required secondary endoscopic procedures. One patient had persistent obstruction 40 days after endopyelotomy at the ureteropelvic junction and, subsequently, required percutaneous resection of a persistent flap of obstructing tissue. In another patient a ureterovesical stricture was noted at the time of stent removal, which was treated by endoscopic incision. All patients have been followed from 1.5 to 3 years postoperatively. Followup diuretic renograms, ultrasound and/or excretory urography demonstrated a patent ureteropelvic junction in all patients and all have remained asymptomatic. Endopyelotomy appears to be safe and effective in treating secondary ureteropelvic junction obstruction in children.

Nonintubated Anderson-Hynes repair of ureteropelvic junction obstruction in 60 patients

We reviewed our experience with 68 consecutive Anderson-Hynes ureteropyeloplasties. The 64 infants, children and young adults ranged from 2 days to 28 years old (median age 2 years), and 28 were less than 1 year old. Intubation was used in only 4 patients: 2 who also underwent ureteral reimplantation for vesicoureteral reflux, 1 with stones in the renal pelvis and 1 with pyonephrosis. We successfully repaired 60 of 64 nonintubated renal units (93.4 per cent). Temporary postoperative ureteral stenting was required for extravasation from 8 renal units (12.5 per cent). Two patients later underwent repeat ureteropyeloplasty for recurrent obstruction. Nephrectomy was performed for pyonephrosis in 1 patient and for a nonfunctioning kidney that had exhibited poor function preoperatively in 1. Prolonged ileus necessitated extended hospitalization in 3 patients (4.6 per cent). We conclude that nonintubated dismembered ureteropyeloplasty for uncomplicated, primary ureteropelvic junction obstruction can be performed safely and successfully, and should be considered the standard treatment. Positioning of the Penrose drain is critical to avoid urinoma formation. When persistent urinary leakage occurs temporary diversion is easy and well tolerated. Hospital stay averaged 12.1 days for patients with extravasation compared to 4.3 days when no extravasation occurred. Immediate preoperative retrograde pyelography did not seem to contribute to postoperative urinary extravasation by causing edema of the ureteral orifice.

Simultaneous repair of bilateral ureteropelvic junction obstruction

Fifteen children with bilateral ureteropelvic junction obstruction underwent simultaneous repair as a single procedure. Dismembered pyeloplasty and ureterocalycostomy were the two procedures used. Ten were performed through anterior subcostal incisions. Posterior lumbotomy provided adequate exposure in 5 children and further contributed to shortened hospitalizations. The functional and anatomic results were excellent. Simultaneous bilateral pyeloplasty through posterior lumbotomy is a safe and cost-effective alternative to staged procedures for bilateral ureteropelvic junction obstruction.

Pediatric pyeloplasty: 50 patients with 59 hydronephrotic kidneys

A report of 59 hydronephrotic kidneys due to pelviureteric junction (PUJ) obstruction in 50 children less than 12 years of age is presented. Thirty-two percent of the patients were less than 1 year of age, with their main presenting feature being an abdominal mass (88%). For older children, loin or abdominal pain was the chief presenting symptom (68%). During infancy, the left and right sides were equally affected, followed closely by bilateral involvement. On the other hand, in older children, the left side was predominantly affected, being twice as common as the right, and the latter again was twice as common as bilateral involvement. Dismembered pyeloplasty was the procedure used in most cases (88%); the nephrectomy rate was 8% for grossly dilated or dysplastic kidneys. During follow-up (of 6 months to 10 years) of 54 pyeloplasties, improvement was seen in 36 (67%), 12 were unchanged (22%), and one reverted to normal (2%) after the initial operation. Two (4%) worsened initially but achieved stabilization after reoperation; the remaining 3 patients (6%) showed unsatisfactory results. Stents were used in 65% of the cases and nephrostomies in 53%.

Ureteropelvic junction obstruction in the neonate

The widespread use of maternal ultrasonography has resulted in an increasing number of asymptomatic newborns being diagnosed with hydronephrosis. A total of 89 neonates with hydronephrosis secondary to ureteropelvic junction obstruction have been referred for evaluation and treatment during the last 6 years. In the majority the condition was diagnosed readily with ultrasonography, voiding cystography and excretory urography. Twenty-five per cent underwent more quantitative assessment using nuclear renal imaging. Only 2 patients (8 per cent) had a percutaneous study. Early reconstruction was performed in 75 per cent of the patients and it proved to be safe and effective. Twenty-three neonates were followed nonoperatively. One patient (4 per cent) demonstrated clinical deterioration necessitating later surgical intervention. Careful surveillance is mandatory in all infants followed nonoperatively.

Ureteropelvic junction obstruction during the first year of life

Over the past three years, 28 children less than one year of age, were operated on for ureteropelvic junction obstruction. Our results demonstrate that congenital hydronephrosis most commonly presents antenatally, and that early postnatal correction can be performed safely. The high surgical success rate, with a relatively short hospital stay (3-4 days), is attributed to early diagnosis, when the pelviureteral tissues are relatively healthy and nephron maturation is at maximum. The practice of delaying surgical correction of an obstructed hydronephrotic kidney on the basis of "stable" renal function is unwarranted, since it denies such kidneys their full potential for recoverability.

Neonatal renomegaly

A retrospective clinical review was done to study the value of ultrasound and renography in the investigation of 100 neonates with renomegaly. Abnormalities in 73 patients were detected antenatally with ultrasonography. Of the neonates 47 had lower urinary tract pathological conditions and ultrasound was more than 90 per cent accurate in identifying the accompanying ureteral dilatation. A total of 53 neonates had upper tract anomalies (ureteropelvic junction obstruction or cystic dysplasia). With ultrasonography the degree of pyelocaliectasis in patients with ureteropelvic junction obstruction was classified as mild (22 units), moderate (13) or severe (7). Initial treatment and followup were reviewed to study the clinical course of neonates with mild to moderate degrees of pyelocaliectasis followed nonoperatively, and to determine whether the diuretic renogram had a predictive role in identifying which kidneys were most likely to deteriorate.

Progression of mild ureteropelvic junction obstruction in infancy

Mild and clinically silent ureteropelvic junction obstruction was observed to progress in severity in 2 infants. Diuretic renography was useful in serial evaluation and documentation of progression. The possible mechanism for such progression of obstruction is proposed. Although mild obstruction in the older child and adult can be followed successfully without surgery, it appears that close follow-up of mild obstruction during the first year of life is necessary to detect and assure treatment of progressive obstruction at an optimum age.

Surgery of pelviureteric obstruction in the first year of life

Twenty-nine out of 108 patients (26%) were under 1 year of age at the time of surgery for congenital pelviureteric obstruction. The clinical features and diagnosis, management, follow-up and results in these patients are reviewed. Clinical presentation was usually with an abdominal mass or urinary infection but an increasing number of cases were diagnosed after maternal ultrasonography had shown hydronephrosis. Ultrasonography, together with renal nuclide scan, were considered to be the most appropriate imaging modalities to define anatomy, determine function and document obstruction. Pyeloplasty was carried out successfully in 28 patients (two bilateral) and one patient had a nephrectomy. Sixteen pyeloplasties were managed by a nephrostomy (with or without a stent), the tubes usually being removed 10-12 days postoperatively. Fourteen pyeloplasties were managed by a wound drain only but one required a secondary nephrostomy although eventual recovery was satisfactory. Renal nuclide scan was found to be the most appropriate follow-up test and the overall results of surgery were satisfactory.

Ureteropelvic junction obstruction in the newborn

Ureteropelvic junction (UPJ) obstruction is a common cause of hydronephrosis in infants. Newborns with severe obstruction often have marked improvement following correction; therefore early diagnosis and operation is important. From 1973 to 1983, 21 patients were operated on for UPJ obstruction diagnosed under 6 weeks of age. Six patients (29%) had antenatal ultrasonographic diagnosis. The remaining patients were diagnosed by IVP or radionuclide scan for palpable renal enlargment or for associated anomalies. Seventeen had unilateral and four had bilateral obstruction. Twenty-three pyeloplasties, one primary nephrectomy, and one cutaneous pyelostomy with subsequent nephrectomy were done. All pyeloplasties were dismembered, with tailoring of the renal pelvis. Postoperative renal function was followed with radionuclide scan or IVP. Postoperative complications included a single urinary tract infection in three patients and two bowel obstructions. One early postoperative death occurred in an infant with bilateral obstruction who developed congestive heart failure secondary to severe uncontrollable hypertension. There were two other unrelated late deaths. Documented functional improvement with minimal complications follow unilateral or simultaneous bilateral pyeloplasty in newborns with UPJ obstruction.

Management of ureteropelvic junction obstruction in infants

The frequent use of fetal ultrasound is allowing early (prenatal) diagnosis of numerous uropathies previously delayed until the child either became symptomatic or had a palpable mass. We would anticipate an increasing number of neonates presenting for repair of obstructions, especially ureteropelvic junction obstruction. To evaluate our experience with this disorder in infants we reviewed our experience with ureteropelvic junction obstruction during the last 6 years in 16 infants less than 1 year old. Principles of evaluation, surgical techniques and results are presented. To date, no secondary procedures have been necessary and most neonates have shown dramatic improvement in the parenchymal mass and intrarenal anatomy.

Ureteropelvic junction obstruction in newborns and infants

Of 11 patients less than 1 year old with ureteropelvic junction obstruction 9 presented with an abdominal mass. The ideal method evaluation of such patients with an abdominal mass includes sonography followed by isotope renal scan if the mass is determined to be urinary in origin. Visualization by excretory urography in this age group is often impaired by poor renal concentrating ability and excessive bowel gas. Repair was achieved successfully using a nonintubated, nonstented, dismembered pyeloplasty in 10 of 13 kidneys. The average postoperative hospital stay for this group was 4.8 days. Three kidneys were diverted temporarily by nephrostomy, leading to a complication in 1 that required secondary repair. Average postoperative hospital stay in the diverted group was 15 days. Renal function was excellent following repair in all patients, suggesting that early repair is highly desirable in this age group.