Does delaying pyeloplasty affect renal function in children with a prenatal diagnosis of pelvi-ureteric junction obstruction?

The conundrum of high-grade hydronephrosis with non-obstructive drainage on diuretic renography

BACKGROUND

Patients with high grade hydronephrosis (HN) and non-obstructive drainage on mercaptoacetyltriglycine (MAG-3) diuretic renography (renal scans) can pose a dilemma for clinicians. Some patients may progress and require pyeloplasty; however, more clarity is needed on outcomes among these patients.

OBJECTIVE

Our primary objective was to predict which patients with high-grade HN and non-obstructive renal scan, (defined as T ½ time <20 min) would experience resolution of HN. Our secondary objective was to determine predictors for surgical intervention.

STUDY DESIGN

Patients with prenatally detected HN were prospectively enrolled from 7 centers from 2007 to 2022. Included patients had a renal scan with T ½<20 min and Society for Fetal Urology (SFU) grade 3 or 4 at last ultrasound (RBUS) prior to renal scan. Primary outcome was resolution of HN defined as SFU grade 1 and anterior posterior diameter of the renal pelvis (APD) < 10 mm on follow-up RBUS. Secondary outcome was pyeloplasty, comparing patients undergoing pyeloplasty with patients followed with serial imaging without resolution. Multivariable logistic regression was used for analysis.

RESULTS

Of the total 2228 patients, 1311 had isolated HN, 338 patients had a renal scan and 129 met inclusion criteria. Median age at renal scan was 3.1 months, 77% were male and median follow-up was 35 months (IQR 20-49). We found that 22% (29/129) resolved, 42% of patients had pyeloplasty (54/129) and 36% had persistent HN that required follow-up (46/129). Univariate predictors of resolution were age≥3 months at time of renal scan (p = 0.05), T ½ time≤5 min (p = 0.09), SFU grade 3 (p = 0.0009), and APD<20 mm (p = 0.005). Upon multivariable analysis, SFU grade 3 (OR = 4.14, 95% CI: 1.30-13.4, p = 0.02) and APD<20 mm (OR = 6.62, 95% CI: 1.41-31.0, p = 0.02) were significant predictors of resolution. In the analysis of decision for pyeloplasty, SFU grade 4 (OR = 2.40, 95% CI: 1.01-5.71, p = 0.04) and T ½ time on subsequent renal scan of ≥20 min (OR = 5.14, 95% CI: 1.54-17.1, p = 0.008) were the significant predictors.

CONCLUSIONS

Patients with high grade HN and reassuring renal scan can pose a significant challenge to clinical management. Our results help identify a specific candidate for observation with little risk for progression: the patient with SFU grade 3, APD under 20 mm, T ½ of 5 min or less who was 3 months or older at the time of renal scan. However, many patients may progress to surgery or do not fully resolve and require continued follow-up.

Does Age Influence the Functional Recovery after Infant Pyeloplasty?

Purpose

The purpose was to study the correlation between age at surgery and functional recovery after infant pyeloplasty.

Materials and Methods

All infants who underwent pyeloplasty were analyzed retrospectively in this multicenter study. Anteroposterior diameter (APD) >2 cm, split renal function (SRF) <40%, and Society of Fetal Urology (SFU) grade 3-4 were surgical indications. Based on the age at pyeloplasty, they were divided into Group 1 (1-3 months) and Group 2 (4-12 months). APD and SRF were compared before and after surgery in both groups. The fractional recoverable function (post-SRF-pre-SRF)/(50-pre-SRF) ×100 was correlated with age.

Results

Fifty-one infants underwent pyeloplasty (mean age: 1.6 months - Group 1 and 7.2 months - Group 2). The mean APD decreased from 3 cm to 1.2 cm in Group 1 while 2.8 cm to 2 cm in Group 2 (P = 0.001). The mean SRF increased from 32.28% to 42.81% in Group 1 while 31%-34.18% in Group 2. SRF recovery was significantly higher in Group 1 compared to Group 2 (P = 0.001). Regression analysis showed a weak negative correlation (r = -0.2792) between age at surgery and renal function improvement.

Conclusion

Functional recovery after pyeloplasty is better when done earlier (1-3 months), as this gives the growing kidney the best opportunity to recover.

Outcome analysis of reduction and nonreduction dismembered pyeloplasty in ureteropelvic junction obstruction: A randomized, prospective, comparative study

Objectives:

Materials and Methods:

Results:

Conclusion:

The obstructive index in antenatal unilateral pelviureteric junction obstruction: A novel predictor of the failure of conservative management

BACKGROUND

To find the impact of the obstructive index (OI) as a predictor of management in antenatal pelviureteric junction obstruction.

METHODS

Records of 135 cases of antenatally detected unilateral pelviureteric junction obstruction, selected for initial observation were retrospectively analyzed. All patients who underwent pyeloplasty on follow up were assigned to Group A. Those patients who were still on conservative management were assigned to Group B. The pelvic anteroposterior diameters of the affected (PAPD[A]) and normal kidney (PAPD[N]) of the same patient, along with the cortical thickness of the affected kidneys (CT[A]) and normal kidneys (CT[N]) on postnatal ultrasound scan, the T1/2 of the affected (T1/2 [A]) and normal kidneys (T1/2 [N]), the differential renal function (DRF), and the shape of the curve on a diuretic renogram were noted for each patient at 6 weeks. The OI was defined as (PAPD[A] × T1/2 [A]) / (PAPD[N] × T1/2 [N]).

RESULTS

The median duration of follow up was 55 months (36-110). Median age at surgery was 12 months (4-80). Group A had 30 patients with 105 in Group B. On multivariate analysis, OI and shape of curve predicted need for surgery with statistical significance. Median OI in Group A was 18.9 compared to 4.82 in Group B (P < 0.001, Mann-Whitney). Using receiver operating characteristic analysis, the area under curve for the OI was 0.95. A level of 12.2 could predict failure of conservative management with a sensitivity of 93.3% and a specificity of 92.4%.

CONCLUSIONS

The OI can reliably predict the need for surgery at a very early stage, thus avoiding repeated tests and saving time.

Functional outcome after neonatal pyeloplasty in antenatally diagnosed uretero-pelvic junction obstruction

Background

With routine antenatal ultrasonography, fetal hydronephrosis is commonly diagnosed. This leads to early detection of postnatal uretero-pelvic junction obstruction which may require surgical intervention. But, there is no clear consensus in the benefits of operating these patients in the neonatal age.

Methods

Aim—To study the functional outcome after pyeloplasty in neonates with antenatally diagnosed unilateral uretero-pelvic junction obstruction (UPJO). Records of all neonates (N = 48) who presented between 2016 and 2018 with prenatal diagnosis of unilateral UPJO and underwent a Anderson-Hyne’s Pyeloplasty were retrospectively analyzed. Indications for surgery were SFU grade 3 or 4, a split renal function (SRF) < 40% on a diuretic renal scan and antero-posterior renal pelvic diameter (APD) > 2.5 cm with parenchymal thinning. Parenchymal thickness (PT) and APD measured by ultrasonography, and SRF measured by 99 m Tc-EC renal scan were compared before and after surgery.

Results

Our study comprised of 48 patients with 79.2% males (n = 38). UPJO affected the left side more (n = 30, 62.5%). The mean age at pyeloplasty was 28 days (range 26–30). The outcome was considered successful in 46 (95.84%) patients. The APD decreased from a mean of 3.5 cm APD preoperatively to 1.38 cm 1 year later which was statistically significant (p < 0.001). The PT increased from 3.95 to 7.1 mm 1 year postoperatively which was significant (p < 0.001). The drainage pattern and SRF improved in 46 (95.84%) patients. The SRF improved from a mean of 35.48–44.7% 1 year postoperatively which was significant (p < 0.001).

Conclusion

Pyeloplasty done in the neonatal age for prenatally diagnosed UPJO, having SFU grade 3–4 UPJO, leads to significant improvement of SRF and PT with minimal complications. Neonatal Pyeloplasty for significant UPJO is a safe procedure which provides the kidney maximum opportunity to improve function.

Outcome analysis of early surgery and conservative treatment in neonates and infants with severe hydronephrosis

Objective

The treatment strategy and timing of ureteropelvic junction obstruction (UPJO) in infants remain controversial. This study aimed to compare the effect of early surgical treatment (EST) and conservative treatment (CT) on neonates and infants with UPJO and their recovery of renal function and morphology.

Methods

Eighty neonates and infants with severe hydronephrosis were enrolled in this study. They received early pyeloureteroplasty or CT. Diethylenetriamine pentaacetate was used to assess renal function.

Results

There were no significant differences in renal function or renal indices at baseline between the two groups. At 3 and 6 months of follow-up, the anteroposterior diameter of the renal pelvis and the Society of Fetal Urology grade in the EST surgery group were significantly lower compared with those at baseline. The thickness of the renal cortex was greater in the EST group than in the CT group at 3 and 6 months of follow-up. After follow-up for 6 months, renal function in the EST group was significantly better than that in the CT group.

Conclusion

EST accelerates the recovery of renal morphological and functional indices in neonates and infants with severe hydronephrosis.

Does Renal Function Remain Stable after Puberty in Children who underwent Ureteral Reimplantation due to Ureterovesical Junction Obstruction?

INTRODUCTION

 Ureteric reimplantation due to ureterovesical junction (UVJ) obstruction enjoys high success in the short term. However, renal function after reimplantation must accommodate the numerous changes in the pediatric urinary tract that occur along with child development that may theoretically cause an occult loss of renal function. The purpose of this study was to evaluate whether improved renal function after ureter reimplantation for antenatal diagnosed UVJ obstruction remains stable after puberty.

MATERIALS AND METHODS

 Twenty-one children who underwent open reimplantation using Politano-Leadbetter technique were followed until they completed puberty. Mean age at surgery was 14.3 months (range: 3-60 months). Five (23.8%) of 21 children had right hydronephrosis, 13 (61.9%) had left hydronephrosis, and 3 (14.3%) had bilateral hydronephrosis. The Society for Fetal Urology (SFU) level of the hydronephrosis was 3 (47.6%) in 10 children and 4 (52.4%) in remaining 11. Fourteen (66.6%) patients had poor renal function upon surgery and the remaining seven (33.4%) patients had moderate renal function. The mean renal function upon operation was 28 ± 4.3 (mean ± standard deviation [SD]).

RESULTS

 Reimplantation led to the increase in the RRF in the short-term period from 28 ± 4.3% prior to the surgery to 36.4 ± 5% (p < 0.001) in all patients and remains stable 35 ± 5% after puberty in all the reviewed patients.

CONCLUSION

 Our data demonstrate for the first time that successful ureteral reimplantation following antenatal diagnosis of UVJ obstruction is associated with an improvement in renal function, not only during short- and midterm follow-up but also allows preserving the renal function throughout the puberty period.

Uretero-Pelvic Junction Stenosis: Considerations on the Appropriate Timing of Correction Based on an Infant Population Treated with a Minimally-Invasive Technique

There is no univocal consensus about timing of intervention and best surgical approach for infants with asymptomatic uretero-pelvic junction obstruction (UPJO). We conducted a retrospective analysis of patients undergoing one-trocar-assisted pyeloplasty (OTAP) in a 13 year range period by creating two homogenous groups (indications for surgery were the same for all patients): patients operated on in the first 90 days of life (34 patients; Group 1) and patients operated on between 3 and 12 months of life (34 patients; Group 2). We observed no statistically significant differences between groups in regard to mean operative time, conversion rate to open surgery, mean hospital stay, early complications (urinary leakage) rate and mean antero-posterior diameter (APD) reduction rate. Moreover, no statistical improvement was seen between groups in regard to separate renal function (SRF) at 1-year-follow-up renogram. Thanks to the HSS calculated before and 1 year after surgery, we registered an important improvement in Group I patients (p = 0.023). In our study, there was no significant evidence, in terms of intraoperative data and early postoperative outcomes, between patients who underwent an early pyeloplasty and those who underwent a delayed correction. Nevertheless, we registered a significant improvement in those patients with an impaired SRF that underwent an early surgical correction, especially in terms of urinary flow. Even though this study cannot definitely establish the superiority of early timing of correction, it is evident that further research is needed to clarify this aspect.

Factors Accountable for Unabated Obstruction Following Pyeloplasty

Purpose:

Split renal function (SFR) and frusemide washout (FWO) are assessed by the DTPA renogram to measure the renal parenchymal functions as well as the evidence of obstruction, both for diagnosis and to treat the pelviureteric junction obstruction. In good number of renal units, both these parameters remain unaltered even after surgery and cause anguish to parents and referring physicians and are usually attributed toward “defective pyeloplasty.” In this study, we have tried to single out the bona fide responsible factor for the bad outcome; either the nonreversible kidney or the restenosis of pyeloplasty.

Patients and Methods:

We studied file of 69 patients in whom a double “J” (DJ) stent was left in situ for internal drainage for a duration of 8 weeks in the postoperative period. DTPA scans were performed preoperative, at 8 weeks with a stent in place, and at 12 and 24 months postremoval of the stent to assess renal function.

Results:

In our study, 45 patients (65.2%) showed improvement either in SRF or in FWO or in both after 8 weeks following pyeloplasty and 24 of 69 units (34.8%) did not show any change in renal function with DJ stent in place. Only in six units (8.7%), out of 69 units had deterioration of renal function after removal of DJ stent.

Conclusions:

In our opinion, no improvement of renal function found in 24 units (34.8%) even with internal drainage with DJ indicates irreversible renal damage. In 45 units (65.2%), renal function reversed after pyeloplasty and DJ stent. However, after the removal of the DJ, functions deteriorated in six units (8.7%) due to restenosis following pyeloplasties.

Management of antenatal hydronephrosis

Antenatal hydronephrosis (AHN) is the most frequently detected abnormality by prenatal ultrasonography. Differential diagnosis of AHN includes a wide variety of congenital abnormalities of the kidney and urinary tract ranging from mild abnormalities such as transient or isolated AHN to more important ones as high-grade congenital vesicoureteral reflux or ureteropelvic junction obstruction. It is well known that the outcome depends on the underlying etiology. Various grading systems have been proposed for the classification of AHN on prenatal and postnatal ultrasonography. Mild isolated AHN represents up to 80% of cases, is considered to be benign, and majority of them resolve, stabilize, or improve during follow-up. Controversies exist regarding the diagnosis and management of some important and severe causes of AHN such as high-grade vesicoureteral reflux and ureteropelvic junction obstruction. Current approach is becoming increasingly conservative during diagnosis and follow-up of these patients with less imaging and close follow-up. However, there is still no consensus regarding the clinical significance, postnatal evaluation, and management of infants with AHN. The aim of this review is to discuss the controversies and provide an overview on the management of AHN.

Early pyeloplasty versus conservative management of severe ureteropelvic junction obstruction in asymptomatic infants

BACKGROUND

Ureteric-pelvic junction obstruction (UPJO) is the most common cause of antenatal and neonatal hydronephrosis and its management remains controversial. While conservative management is advocated for all, this strategy puts a quarter of these patients at risk for possibly irreversible renal damage.

AIM

In this study, we compare functional and anatomic outcomes in newborns and infants less than 1 year of age with high-grade unilateral UPJO, following early surgical pyeloplasty (ESP) versus conservative management (CM).

MATERIALS AND METHODS

This was a single center prospective interventional study. Infants referred to our tertiary care pediatric surgery clinic between September 2016 and September 2018 with UPJO were considered. To be included patients must have been less than 1 year old, lack of clinical symptoms, suffer from severe hydronephrosis as defined by Society for Fetal Urology (SFU) grades 3 or 4, and have affected kidney Split Renal Function (SRF) above 40%. Patients with bilateral disease, structural anomalies, or an abnormal voiding cystourethrogram (VCUG) were excluded. Anatomical and functional outcomes were measured and compared at 6 and 12 months.

RESULTS

Fifty-six patients were assigned to receive either ESP (n = 28) or CM (n = 28). At 6 months Cortical thickness, polar length, and SFU indices were significantly lower in the ESP group, while none of the outcomes were significantly different between the two groups at 12 months. Despite the two groups not being different at 12 months regarding differential renal function (DRF), there was a significant decrease of function in the CM group compared to baseline.

CONCLUSION

When considering treatment options for infants with high-grade UPJO, it appears that ESP hastens improvement of anatomic and functional indices, while CM may lead to a significant deterioration in renal function.

Changes in differential renal function after pyeloplasty in infants and children

INTRODUCTION

Ureteropelvic junction obstruction (UPJO) is one of the most common causes of hydronephrosis in pediatric populations. Many need surgical intervention. The aim of surgery is preserving renal function and reducing symptoms such as urinary tract infections and pain.

OBJECTIVES

The objectives were to evaluate differential renal function (DRF) in infants and children after surgery for UPJO and to identify factors predicting postoperative improvement. The difference in outcomes between patients with antenatal hydronephrosis and those diagnosed later was evaluated.

STUDY DESIGN

A total of 85 children (63 boys and 22 girls) aged 0-16 years, treated for UPJO with dismembered pyeloplasty, were followed up as per a structured protocol including ultrasounds and renal scans (MAG-3) pre-operatively and three and 18 months postoperatively. Five children with bilateral or single kidney UPJO were excluded. Patient records were retrospectively reviewed, and the patients were grouped as per prenatal (group 1, n = 23) or postnatal (group 2, n = 57) diagnosis. Univariable and multivariable logistic regression analyses searching for factors predicting >5% postoperative improvement in DRF on the obstructed side were performed. Factors included in analyses were age at diagnosis and surgery, sex, type of presentation, cause of obstruction, estimated glomerular filtration rate, pre-operative DRF, anteroposterior diameter (APD), APD/renal parenchymal thickness, and grade of hydronephrosis as per the Onen alternative grading system (grade 1-4).

RESULTS

Pre-operative DRF on the obstructed side was a mean of 42% (standard deviation, 12), with no difference between the groups. The median age at surgery was 0.9 (0.2-10) and 8.1 (0.6-16) years in groups 1 and 2, respectively (P < 0.001). The majority had unchanged DRF 18 months postoperatively, 19 (27%) patients improved by >5%, and one deteriorated. The proportion of patients with improved DRF was higher in group 1 (n = 10; 45%, P = 0.026). Anteroposterior diameter, APD/parenchymal thickness, pre-operative DRF, and antenatal diagnosis were predictors in the univariable analyses, and high APD (odds ratio [OR] = 1.1, P = 0.0023), antenatal diagnosis (OR = 0.23, P = 0.048), and low pre-operative DRF (OR = 0.90, P = 0.0045) built the best model of independent factors predicting improvement in DRF in multivariable analyses (Summary Figure).

DISCUSSION

The limitation of the study is that it is retrospective, but it has the advantage of a uniform follow-up protocol, including patients from a five-year period, with few lost to follow-up. The results can be of interest in evaluating factors of importance for predicting recovery of function in obstructive uropathies in children.

CONCLUSION

The majority of children had preserved or improved function after surgery for UPJO. Those with an antenatal diagnosis displayed a greater ability to catch up in DRF, and high APD, antenatal diagnosis, and low pre-operative DRF were independent predictive factors of an improvement in renal function after pyeloplasty.

Symptomatology and Clinic of Hydronephrosis Associated With Uretero Pelvic Junction Anomalies

The most common cause of hydronephrosis in the pediatric age group is ureteropelvic junction-type hydronephrosis (UPJHN). Since the advent of widespread maternal ultrasound screening, clinical presentation of hydronephrosis associated with UPJ anomalies has changed dramatically. Today most cases are diagnosed in the prenatal period, and neonates present without signs or symptoms. For those who are not detected at birth, UPJHN eventually presents throughout childhood and even adulthood with various symptoms. Clinical picture of UPJHN highly depends on the presence and severity of obstruction, and whether it affects single or both kidneys. Abdominal or flank pain, abdominal mass, hematuria, kidney stones, urinary tract infections (UTI), and gastrointestinal discomfort are the main symptoms of UPJHN in childhood. Other less common findings in such patients are growth retardation, anemia, and hypertension. UTI is a relatively rare condition in UPJHN cases, but it may occur as pyelonephritis. Vesicoureteric reflux should be kept in mind as a concomitant pathology in pediatric UPJHN that develop febrile UTI. Although many UPJHN cases are known to improve over time, close clinical observation is critical in order to avoid irreversible kidney damage. The most appropriate approach is to follow-up the patients considering the presence of symptoms, the severity of hydronephrosis and the decrease in kidney function and, if necessary, to decide on early surgical intervention.

Value of urinary carbohydrate antigen 19-9 to predict failure of conservative management in children with ureteropelvic junction obstruction

OBJECTIVE

To assess the role of urinary carbohydrate antigen 19-9 (CA19-9) measurement in determining optimal management of ureteropelvic junction obstruction (UPJO) and predicting failure of conservative management.

PATIENTS AND METHODS

Children with UPJO diagnosed between December 2012 and April 2015 were included. Depending on clinical and para-clinical findings, patients were divided into three groups: Group 1 consisted of patients who were considered for non-operative management with improvement of the condition during the course of follow-up. Group 2 were suitable for observation; however due to deterioration of condition pyeloplasty was indicated after a period of observation. Group 3 patients required immediate pyeloplasty. Urinary CA19-9 was measured in all patients at baseline and compared between the study groups.

RESULTS

A total of 112 children (115 affected kidneys) with UPJO and mean age of 18.6 ± 3.3 months were assessed. Group 1, 2, and 3 consisted of 54(48.2%), 24(21.4%), and 34(30.4%) patients, respectively. Mean baseline urinary CA19-9 was 37.83 ± 5.20, 145.45 ± 18.38 and 244.62 ± 41.42 in groups 1, 2 and 3, respectively. Multivariate analysis showed that both CA19-9 and APD are independent predictors of need for surgery in patients on observation. ROC curve analysis revealed that urinary CA19-9 level at cut off value of 52.6 U/mL had sensitivity of 92.0% and specificity of 70.9% in predicting failure of non-operative management.

CONCLUSION

Higher urinary CA19-9 level is associated with failure of non-operative management in patients with UPJO. Such patients may require close follow-up and assessments to prevent irreversible damage to the kidney.

TYPE OF STUDY

Study of Diagnostic Test.

LEVEL OF EVIDENCE

Level II.

Prenatal and postnatal urinary tract dilation: advantages of a standardized ultrasound definition and classification

Urinary tract dilatation is identified sonographically in 1-2% of fetuses and reflects a spectrum of possible nephro-uropathies. There is significant variability in the clinical management of individuals with prenatal urinary tract dilatation to postnatal urinary pathologies, because of a lack of consensus and uniformity in defining and classifying urinary tract dilation. Ultrasonography is the first step to screen and diagnose kidneys and the urinary tract diseases of the children. The need for a correct ultrasound approach led to the realization of algorithms aimed at standardizing the procedures, the parameters and the classifications. Our objective was to highlight the strengths of the Classification of Urinary Tract Dilation (UTD) suggested by the Consensus Conference which took place in 2014 with the participation of eight Scientific Societies and was subsequently published on the Journal of Pediatric Urology. Before its spread out, the definition of UTD was not uniform and the ultrasonographic measurements were not clearly defined, leading to misunderstandings between physicians. The Classification by the Consensus Conference of 2014 represents a revolutionary tool for the diagnosis and management of UTD. Furthermore, the parameters suggested by the classification proposed are applicable for both prenatal and postnatal classification, ensuring a correct follow-up in children with UTD whose diagnosis had been already made during pregnancy.

Is it Always Necessary to Treat an Asymptomatic Hydronephrosis Due to Ureteropelvic Junction Obstruction?

The postnatal treatment of asymptomatic unilateral hydronephrosis due to ureteropelvic junction obstruction remains controversial, and the timing of and indications for surgical intervention are continuously debated. There is no consensus on the best follow-up during expectant management. The various modalities and parameters have been discussed along with their pros and cons and an attempt has been made to clear up the controversies.

The role of urinary KIM-1, NGAL, CA19-9 and β2-microglobulin in the assessment of ureteropelvic junction obstruction in adults

PURPOSE

The objective of this study is to evaluate the diagnostic properties of urinary biomarkers in adults with ureteropelvic junction obstruction: KIM-1, NGAL, CA19-9, and β2-microglobulin. We also assessed urinary biomarker concentrations following pyeloplasty.

MATERIAL AND METHODS

We prospectively studied adults from December 2013 to February 2015. We included 47 patients with a mean age of 38.6 ± 12.7 years. Each patient provided four samples of voided urine for biomarker measurement, one at pre-operative consultation and the others at 1, 3, and 6 months of post-operative follow-up. The control group consisted of 40 healthy individuals with no hydronephrosis on ultrasound evaluation.

RESULTS

KIM-1 had an area under the curve of 0.79 (95% CI 0.70-0.89), NGAL 0.71 (95% CI 0.61-0.83), CA19-9 0.70 (95% CI 0.60-0.81), and β2-microgloblin 0.61 (95% CI 0.50-0.73). KIM-1 was the most sensitive marker with a cut-off of 170.4 pg/mg creatinine (sensitivity 91.4%, specificity 59.1%), whereas CA19-9 was the most specific with a cut-off of 51.3 U/mg creatinine (sensitivity 48.9%, specificity 88.0%). Urinary concentrations of biomarkers decreased after pyeloplasty.

CONCLUSIONS

The evaluation of urinary biomarkers is useful in adults undergoing pyeloplasty. KIM-1, NGAL, and CA19-9 were elevated and significantly decreased after surgery.

Benefit of F-15 protocols in equivocal F + 20 MAG3 renography in children with upper tract dilatation and symmetric split function: Results and outcomes

PURPOSE

In children with upper tract dilatation, diuretic renography, which includes application of mercaptoacetyltriglicin-99 mTc (MAG3), is the standard examination. Ordinarily, furosemide is applied 20 min after tracer injection (F + 20). In children with persistent hydronephrosis and preserved split function, this protocol may lead to further examinations with repeatedly equivocal washout curves. The present study evaluated the potential of MAG3 (F-15) scans in this subgroup of children to achieve a conclusive result avoiding additional equivocal MAG3 (F + 20) scans.

OBJECTIVE

To evaluate whether the washout curve using the F-15 protocol is a helpful criterion with which to clarify results in patients with equivocal patterns in the F + 20 protocol.

PATIENTS

31 children (male/female 22/9, median age at time of examination 42 months, mean anterioposterior diameter 2.1 cm, left/right 14/18) underwent MAG3 F-15 renography at the present department because of upper urinary tract dilatation and (repeatedly n ≥ 2 F + 20 = 28) equivocal results in MAG3 F + 20 examinations.

RESULTS

In 10/31 children (32.2%), MAG3 F-15 revealed an obstructive pattern, indicating a pyeloplasty in 9/10 of them (90%). In 16/31 children (51%), the F-15 protocol showed a non-obstructive curve, leading to further uneventful follow-up in 15/16 of them (93.7%). In 5/31 children (16%), MAG3 F-15 led to equivocal results, resulting in no pyeloplasty and further uneventful follow-up in all the children (mean follow-up 1.46 years).

DISCUSSION

In children with persistent high-grade hydronephrosis on ultrasound and preserved split function, multiple scans were prompted and further management was sometimes difficult. Although there was proven evidence that the F-15 protocol reduced the frequency of equivocal pattern, there was no indication for primary F-15 investigation, due to the risk of over diagnosis of obstruction. The F-15 scan was considered to be a stress test of the upper tract leading to a diuretic challenge without any opportunity to investigate normal washout curve. In these cases, partial obstruction could lead to false positive obstructive results. A stepwise approach, in which the traditional F + 20 technique allows observation of the rate of washout of radiopharmaceuticals before forced diuresis followed by a F-15 protocol, could reduce the child's additional radiation burden and stress.

CONCLUSION

After equivocal results in MAG3 F + 20 protocols, performing a MAG3 F-15 exam lead to a conclusive result in 80.6% (25/31 patients) of the cases. Thus, performing a MAG3 (F-15) exam can be recommended in children with persistent hydronephrosis and preserved split function after equivocal results on MAG3 (F + 20) scans.

Is decreased diameter of renal pelvis in prone position an indicator of successful pyeloplasty?

OBJECTIVE

To evaluate patients who had undergone pyeloplasty for pelviureteric junction obstruction, by measuring the anteroposterior diameter (APD) of the renal pelvis in supine and prone positions, and determine whether a decrease in APD in prone position can exclude obstruction in dilated renal system.

MATERIALS AND METHODS

From January 2012 to December 2013, patients who had undergone pyeloplasty were evaluated by ultrasound in two centers. The difference of APD of the renal pelvis in supine and prone positions was obtained. Correlation was made with the pre- and post-pyeloplasty renal function by radionuclide renogram.

RESULTS

There were 42 patients (31 males, 11 females; age range 5 months to 18 years). Residual hydronephrosis was detected in 41 patients of whom 35 patients (85%) showed decrease in APD by >10% in prone position. These patients and the one without hydronephrosis showed either no deterioration or improvement in renal function. Six patients (15%) showed either no change or increase in APD in prone position. Three patients (7.5%) were confirmed to have decrease in renal function indicating obstruction. Three patients (7.5%) showed no deterioration of renal function, but sluggish drainage on radionuclide renogram.

CONCLUSION

Demonstration of decreased APD of renal pelvis in prone position by ultrasound is useful to differentiate obstructed from non-obstructed dilated renal system, and it correctly identified 85% candidates with successful pyeloplasty. In patients with no decrease or increase in APD at prone position, further follow-up is recommended to rule out obstruction.

The effect of preoperative urinary tract infection on postoperative renal function in prenatally diagnosed ureteropelvic junction obstruction: Indications for the timing of pyeloplasty

PURPOSE

We reviewed renal function after pyeloplasty (PP) in cases of prenatally diagnosed ureteropelvic junction obstruction (PDUPJO) to determine the impact of preoperative urinary tract infection (UTI) on the timing of PP.

METHODS

We retrospectively reviewed 81 cases of PDUPJO diagnosed between 1998 and 2013. Incidence of UTI was used to divide 37 kidneys requiring PP (3 bilateral) into U(-): UTI≤1; n=25, and U(+): UTI≥2; n=12 to compare age at PP, grade of hydronephrosis (HN) on ultrasonography (US), glomerular filtration rate (GFR) on diethylenetriaminepentacetic acid (DTPA) renography, and uptake on dimercaptosuccinic acid (DMSA) scintigraphy pre/post PP.

RESULTS

Age at first UTI and age at PP were similar. HN improved significantly postPP in all cases. Although DTPA and DMSA were similar prePP, improvement postPP was better in U(-) than U(+), but only DMSA in U(-) was statistically significant (15.2%±4.0% vs. 20%±3.7%; p=0.049). There were no complications or UTI postPP.

CONCLUSION

Two or more UTIs would appear to be associated with postPP renal dysfunction in PDUPJO. Thus, PP should be performed after the initial UTI but before the second UTI.

Is a Reassuring MAG-3 Diuretic Renal Scan Really Reassuring?

Objective

The mercaptoacetyltriglycine-3 (MAG-3) diuretic renal scan is frequently used to diagnose obstruction in children with hydronephrosis. However, it remains unclear whether a reassuring MAG-3 diuretic scan in the presence of high-grade hydronephrosis accurately predicts the absence of obstruction. We sought to determine if a reassuring nuclear scan can accurately identify patients with high-grade hydronephrosis that can be safely observed.

Materials and Methods

We retrospectively reviewed the course of 22 children (25 renal units) ages 0-3 months with significant hydronephrosis (Society of Fetal Urology grade 3-4) detected prenatally. All patients underwent a MAG-3 diuretic nuclear renal scan.

Results

Twenty-two patients with 25 renal units were included, 19 with grade 3 and 6 with grade 4 hydronephrosis on ultrasound. Sixteen renal units had a reassuring nuclear scan (T ½ < 10 minutes, average 5.9, range 2-9). Nine renal units had indeterminate scans (T ½ 10-20 minutes, average 12.8, range 10-17). Fifteen of 16 (94%) kidneys with a reassuring nuclear scan had complete resolution of their hydronephrosis. One patient with an initially reassuring nuclear scan underwent pyeloplasty after persistent grade 4 hydronephrosis one year later prompted a repeat MAG-3 indicating obstruction. Eight of 9 (89%) patients with an indeterminate T ½ of 10-20 minutes had complete resolution of their hydronephrosis. One patient was lost to follow up. Average length of follow up and time to resolution was 23.6 months (range 4-61 months).

Conclusion

In pediatric patients with persistent antenatally detected hydronephrosis, a reassuring MAG-3 can allow for safe observation in the vast majority. Only one of 24 renal units with follow-up progressed to obstruction. All patients treated without surgery had complete resolution of their hydronephrosis. Observation with serial ultrasounds may be an appropriate alternative to operative management, even in patients with moderate to severe hydronephrosis in the presence of a reassuring or indeterminate MAG-3 diuretic scan.

Functional outcomes of early versus delayed pyeloplasty in prenatally diagnosed pelvi-ureteric junction obstruction

Although initial conservative management is popular in the management of antenatally detected pelvi ureteric junction (PUJ) obstruction [1-3], several authors [4,5] have questioned this approach and expressed concern about failure to recover the function lost during expectant management following surgery. In this single center prospective study, we have compared the functional outcomes following early versus delayed pyeloplasty in SFU grade 3-4 PUJ obstruction.

METHODS

Among those children, who presented between 2004 and 2013, with prenatal diagnoses of unilateral PUJ obstruction (n = 886), those with SFU grade 1 or 2 hydronephrosis on USG (n = 533) were excluded. In the remaining 353 children with SFU grade 3 and 4 hydronephrosis, 243 had obstructive pattern on radionuclide scan. After excluding those with severely impaired or supranormal split renal function (SRF), palpable mass, single kidney status, bilateral disease and associated other urological anomalies a total of 126 children were included in the study group. Parents who were unwilling for a frequent follow-up underwent early pyeloplasty, (Group I: n = 62) while the remaining underwent initial conservative management, with 3 monthly USG and nuclear scans (Group II; n = 64). In this group pyeloplasty was performed whenever there was deterioration in SRF >10%, or urine infection or pain during the follow-up. A standard open dismembered pyeloplasty was performed by the same surgeon in all patients. Radionuclide scan was performed at 1 year, at the same center using the same protocol, to assess final SRF and drainage. The functional outcomes were compared using student's t test and chi square test.

RESULTS

Group I comprised of 62 patients while Group II 64 patients. The mean age at pyeloplasty was 2.8 months in group I while 12.5 months in group II. There was no significant difference in the initial antero posterior diameter (APD) between the groups; 30.2 (±3.2) mm in group I and 29.6 (±3.7) mm in group II. At 1-year follow up after surgery, there was improvement in the APD, 16.8 (±4.2) mm in group I and 18.2 (±4.5) mm in group II, with no significant difference between them. In group I, the initial mean SRF was 34.1% (±6.4) and there was significant improvement (p = 0.01) in mean SRF to 37.2 (±7.1) at 1-year follow up after surgery. In group II, the mean SRF was 35.9 (5.7) initially and there was a deterioration to 32.6 (±5.5) before surgery (Figure). At 1-year follow up after surgery, there was a marginal improvement to 33.5 (5.6), however it was significantly lower compared to the initial SRF (p = 0.01). Compared to initial function, at 1-year follow up after pyeloplasty, SRF improved in significantly higher number of patients; 17/62 (27.4%) in group I while only 7/64 (10.9%) in group II (p = 0.03) (Table). There was significantly fewer patients with deterioration in final SRF at 8/62 (12.9%) in group I compared to 22/64 (34.4%) in group II (p = 0.03).

DISCUSSION

Although several publications [1-3] have reported functional recovery during initial conservative treatment of PUJ obstruction, in our study a large proportion of patients (80%) in Group II had loss of function during follow-up. This is probably because the study population included only SFU grade 3-4 with obstructive renogram. Several authors have expressed concern about irreversible loss of renal function during expectant management [4,5]. Findings of our study reveal that irrespective of initial SRF, early pyeloplasty in prenatally diagnosed SFU grade 3-4 PUJ obstruction leads to significant improvement of SRF, while delayed pyeloplasty leads to a marginal but, significant loss. This fact should be highlighted to parents so that informed decisions can be made regarding early versus delayed surgery.

Symptomatic versus asymptomatic pyeloplasties: A single institution review

INTRODUCTION

Historically, pyeloplasties have been performed after symptoms and radiographic confirmation of an ureteropelvic junction obstruction (UPJO). However, with prenatal ultrasonography, the approach to patients has fundamentally changed. Increasingly, patients are diagnosed and treated before the advent of morbidity, based on imaging findings alone. However, optimum screening strategies and thresholds for intervention vary significantly, are controversial, and are not founded on outcome-based evidence. We examined all pyeloplasties performed at our institution and reviewed their indication for surgery. We hypothesized that, despite ubiquitous screening for UPJO, most pyeloplasties had been performed secondary to symptoms and did not benefit from antenatal screening.

METHODS

A retrospective chart review was performed of all pyeloplasties performed at the Stollery Children's Hospital, Edmonton, Alberta, over the past 8 years. Patients were categorized according to indication for surgery: symptomatic or asymptomatic.

RESULTS

Most (60%) of our pyeloplasties were performed for symptomatic indications. Furthermore, 12% of these patients had antenatally detected hydronephrosis that was thought to have resolved spontaneously during follow-up. Of our symptomatic patients, 37% were undergoing surveillance with the expectation for spontaneous resolution. Of the 29 patients who underwent pyeloplasty, 8 suffered a preoperative loss of function on renal scans; however, only 50% returned to within 90% of their original function.

CONCLUSION

Despite active surveillance of antenatally detected hydronephrosis, most pyeloplasties at our institution were performed for de-novo symptoms. We believe that this simple observation reinforces that our current surveillance strategies are unable to predict and eliminate all morbidity from UPJO.

White-blue pyelocalyceal cyst with hydrotic glomerulonephritis

A 5-month-old male infant presented with a 15 day history of distension of abdomen. On clinical examination, a soft lump was palpable in the left lumbar region. Radiological findings suggested an enlarged non-functional left kidney with ureteropelvic adhesive obstruction. The left renal mass was excised and submitted for histopathological examination. The excised renal mass was cystic with its wall partly white and partly blue. Gross and histopathological findings were diagnostic of a white-blue pyelocalyceal cyst with hydrotic glomerulonephritis. This entity needs to be differentiated from a large number of other cystic diseases of the kidney. Intrauterine screening and diagnosis may be significant for a possible early intrauterine uro-laparoscopic recanalisation of the pyeloureteral obstruction to save the affected kidney.

Revised guidelines on management of antenatal hydronephrosis

Widespread antenatal screening has resulted in increased detection of anomalies of the kidneys and urinary tract. The present guidelines update the recommendations published in 2000. Antenatal hydronephrosis (ANH) is transient and resolves by the third trimester in almost one-half cases. The presence of oligohydramnios and additional renal or extrarenal anomalies suggests significant pathology. All patients with ANH should undergo postnatal ultrasonography; the intensity of subsequent evaluation depends on anteroposterior diameter (APD) of the renal pelvis and/or Society for Fetal Urology (SFU) grading. Patients with postnatal APD exceeding 10 mm and/or SFU grade 3-4 should be screened for upper or lower urinary tract obstruction and vesicoureteric reflux (VUR). Infants with VUR should receive antibiotic prophylaxis through the first year of life, and their parents counseled regarding the risk of urinary tract infections. The management of patients with pelviureteric junction or vesicoureteric junction obstruction depends on clinical features and results of sequential ultrasonography and radionuclide renography. Surgery is considered in patients with increasing renal pelvic APD and/or an obstructed renogram with differential renal function <35-40% or its subsequent decline. Further studies are necessary to clarify the role of prenatal intervention, frequency of follow-up investigations and indications for surgery in these patients.

Dismembered and non-dismembered retroperitoneoscopic pyeloplasty for the treatment of ureteropelvic junction obstruction in children

PURPOSE

Open dismembered pyeloplasty according to Anderson-Hynes (AHP) is the gold standard treatment for ureteropelvic junction obstruction in children. However, during the last decade, the management has been revolutionized with introduction of laparoscopy and endourology yielding comparable results and less morbid outcomes.

METHODS

Between 1997 and 2010, dismembered and non-dismembered retroperitoneoscopic pyeloplasty was performed in 41 children with a median age of 130 month (range 5-192). 20 children underwent a dismembered pyeloplasty (Anderson-Hynes) and 21 children were operated by a non-dismembered pyeloplasty (Y-V-Plasty).

RESULTS

The mean operation time was 120 min (range 52-257). Intraoperative findings revealed in 29 cases a significant crossing vessel. Based on a furosemide nephrogram and subjective complaints, the success rate was 88 % with a median follow-up of 69 month (range 14-142). The 5 failures (2 Y-V-Plasty, 3 AHP) have been treated by open AHP (n = 2), Laser endopyelotomy (n = 2) and Lap-AHP (n = 1) without further problems.

CONCLUSION

With increasing improvement of the suture techniques, the laparoscopic pyeloplasty represents in experienced hands an alternative method with comparable success rates to the open technique. In our opinion, retroperitoneoscopic pyeloplasty is technically possible and feasible even in infants. We found in our series no statistically significant difference between dismembered and non-dismembered pyeloplasty.

Pelvis/cortex ratio: an early marker of success following pyeloplasty in children

OBJECTIVES

To document the change in anterio-posterior pelvic diameter (APPD), cortical thickness (CT) and pelvis/cortex ratio (P/C ratio) following pyeloplasty, and determine the usefulness of each of these parameters in assessing postoperative outcome.

PATIENTS AND METHODS

Twenty-four children with unilateral pelvi-ureteric junction obstruction who underwent standard dismembered pyeloplasty with stent were prospectively studied (median age 13 months; range 2 months-5 years). Maximum APPD, CT and P/C ratio values were compared pre- and postoperatively.

RESULTS

Mean APPD was 40.70 mm preoperatively, and 30.04 mm at 3 months and 12.75 mm at 1 year postoperatively. The reduction in size at 3 months was not significant (P = 0.34), but was significant at 1 year (P < 0.01). Mean CT was 4.41 mm preoperatively, 6.29 mm at 3 months and 9.45 mm at 1 year. The increase in CT was not significant at 3 months (P = 0.44), but was significant at 1 year (P < 0.01). The P/C ratio was 13.48 mm preoperatively, 5.73 mm at 3 months and 1.45 mm at 1 year. The reduction in P/C ratio was significant at 3 months (P < 0.01) as well as at 1 year (P < 0.01). Sonographic resolution rate did not correlate with outcomes on radionuclide scans.

CONCLUSION

P/C ratio could be used as an early marker of success following pyeloplasty. Improvement in other sonographic criteria or on radionuclide scans may be useful only in the long term.

Long-term follow-up and management of prenatally detected, isolated hydronephrosis

PURPOSE

The aim of the study was to determine the outcome and management of infants with isolated hydronephrosis, detected prenatally and confirmed postnatally.

MATERIALS AND METHODS

Between January 1988 and January 2008, the files of 629 children (492 males and 137 females), who were diagnosed prenatally with isolated, unilateral hydronephrosis, and the diagnosis was confirmed postnatally, were retrospectively reviewed. The median follow-up time was 142 months. Serial ultrasonography and isotope diuretic renography nuclear imaging were performed. Hydronephrosis was assessed and classified according to the Society of Fetal Urology (SFU) grading system.

RESULTS

Initially, all of the children were treated conservatively. Stabilization occurred in all children with grade 1 hydronephrosis, in 87% of children (144) with grade 2 hydronephrosis, and in 30% of children (37) with grade 3 hydronephrosis. However, 13% of children (21) with grade 2 hydronephrosis, 70% of children (85) with grade 3 hydronephrosis, and 100% of children with grade 4 hydronephrosis received surgical intervention according to our predetermined criteria. Ninety-five patients (late pyeloplasty group) were treated for a reduction for a differential renal function (DRF) to less than 40%, and 80 children (early pyeloplasty group) underwent surgery for a DRF more than 40%, but hydronephrosis progressed to higher grades or failed to improve and had poor radiotracer clearance. Significant improvements after pyeloplasty were noted in both groups with respect to the DRF and the ratio of the depth of the calyces to the thickness of the parenchyma (C/P ratio; P < .0001). The improvement in DRF was greater in the late pyeloplasty group than the early pyeloplasty group (P = .044), whereas the improvement in the C/P ratio was greater in the early pyeloplasty group than the late pyeloplasty group (P = .001). The ipsilateral DRF was preserved in the early pyeloplasty group, whereas the ipsilateral DRF was still less than 40% in the late pyeloplasty group. The improvement in DRF was significant during the first year postoperatively and became stable thereafter. The C/P ratio was inversely correlated with the DRF in the patients before and after pyeloplasty (r = -0.257; P = .01; and r = -0.616; P = .001, respectively).

CONCLUSIONS

All infants with SFU-1 and most infants with SFU-2 hydronephrosis have relatively benign conditions and do not need an invasive procedure. Although greater improvement occurred in patients with an initial DRF less than 40%, the reduced DRF did not recover to the predeterioration level postoperatively. Earlier surgical intervention after a short period of strict clinical surveillance is beneficial for preserving renal function for patients with persistent SFU-3 or SFU-4 hydronephrosis.

Pyeloplasty in children: is there a difference in patients with or without crossing lower pole vessel?

INTRODUCTION

Most of the children with hydronephrosis do not require any surgical intervention. However, in individual cases, irreversible loss of renal function can develop. Predictive criteria have been proven ineffective so far in determining in which children obstruction will lead to renal damage. The aim of our retrospective study was to determine the role of a crossing lower pole vessel (CV) in children undergoing pyeloplasty.

MATERIALS AND METHODS

Between 1996 and 2003, 137 patients (age between 6 weeks and 16 years) with unilateral ureteropelvic junction obstruction and no associated urological pathologies underwent Anderson-Hynes dismembered pyeloplasty. A total of 112 patients were evaluated with complete data. One of the following criteria was considered to be indication for surgery in children with grade 4 hydronephrosis: differential renal function (DRF) <40%; clinical symptoms such as pyolenephritis and flank pain; during follow-up renographies, a reduction of DRF >10% and washout patterns II or III b according to O'Reilly. We looked at the age during surgery and the kind of presentation. DRF was measured using diuretic renography preoperatively and 1 year postoperatively. A postoperative change in DRF of group A (children without CV, n = 84) was compared to that in group B (children with CV, n = 28).

RESULTS

Median age at the time of surgery was 5 months in group A compared to 23 months in group B. Only in 21.4% of the children with CV compared to 60.7% without CV hydronephrosis was diagnosed by ultrasound examination antenatally. We found a preoperative DRF of 42.4% +/- 11.2 SD in group A, and of 38.9% +/- 11.7 SD in group B. The percentage of postoperative improvement was 3.3% in group A and 15.4% in group B.

CONCLUSIONS

Children with ureteropelvic junction obstruction and CV received a delayed surgical treatment and showed a greater reduction in differential renal function preoperatively, in contrast to patients without CV. Our data show that CV is a risk factor for deterioration of renal function in children with hydronephrosis and we advocate for an early pyeloplasty in these children, especially if they have a high-grade dilatation and equivocal washout patterns in diuretic renographies. Further prospective studies are necessary in order to understand the natural history of CV and to reveal the importance of the crossing lower pole vessel as a structural anomaly lacking maturation.

[Postnatally hydronephrosis (HN) in children with antenatally diagnosed hydronephrosis: surgery or medical treatment?]

OBJECTIVES

There is no formal agreement or criteria utilized to establish a standard of treatment in children with antenatally diagnosed HN.

METHODS

We analyzed our own experience in addition to the protocols attending to this subject. Twenty eight (28) children with unilateral HN were assessed from October 1999 through October 2005 and the anteroposterior diameter of renal pelvis (APDP) was measured.

RESULTS

Patients underwent surveillance with US and cintilography in 3, 6, 12 and 24 months. The treatment results were reviewed following the classification of Society of Fetal Urology: slight (2 to 5 mm), moderate (6 to 10 mm) and severe (> 10-15 mm).

CONCLUSIONS

We concluded that slight HN would never be operated on while the severe ones would always be. The moderate HN, on the other hand, would remain under surveillance with US and cintilography for two years.

Long-term follow up of antenatally diagnosed megaureters

AIM

We have retrospectively evaluated our 17 years of experience with antenatal diagnosis of hydronephrosis that led to postnatal diagnosis of megaureter, and tried to determine criteria for surgery.

PATIENTS AND METHODS

Seventy-nine children (64 boys and 15 girls) with antenatal diagnosis of hydronephrosis that led to postnatal diagnosis of megaureter were followed conservatively over a period of 18 years (1988-2006). Right ureterohydronephrosis was seen in 23 children, left in 30 and 26 had bilateral ureterohydronephrosis comprising a total of 105 renal units (RU). According to SFU (Society for Fetal Urology) classification, 8 RU were grade 1, 57 grade 2, 29 grade 3 and 11 grade 4 postnatal hydronephrosis. Mean ureteral diameter was 1.2 cm. Relative renal function was in 82 RU more than 40%, in 18 RU 30-40% and in 5 RU less than 30%. Functional deterioration of the hydronephrotic kidney of more than 5%, worsening of hydronephrosis (SFU upgrade) and a persistent obstructive curve on radionuclide scans were the main indications for surgery.

RESULTS

Twenty-five (31%) children required surgical correction. Mean age at surgery was 14.3 months (range 3-60). Univariate analysis revealed that gender and side of obstruction are not significant predictive factors for surgery SFU grade 3-4 of postnatal hydronephrosis, Relative renal function less than 30% and ureteral diameter more than 1.33 cm were significant independent risk factors leading to reimplantation.

CONCLUSIONS

Only 30% of children with antenatal diagnosis of megaureter required surgical correction. Renal function less than 30%, grades 3 and 4 hydronephrosis, and ureteric diameter more than 1.33 cm are statistically significant and independent predictive factors for surgery.

Antenatally detected urinary tract abnormalities: more detection but less action

We present the findings of a prospective cohort study of babies born with antenatally detected urinary tract abnormalities (AUTAs) between 1999-2003 and compare the outcomes with those of an earlier cohort born between 1989 and 1993. All infants with a fetal anteroposterior renal pelvic diameter (APRPD) > or =7 mm in the third trimester or other urinary tract abnormality underwent a detailed postnatal ultrasound scan and other investigations as indicated. The incidence of AUTAs was significantly greater in the more recent cohort (7.6/1000 vs. 3/1000 live births; p<0.05). Of the 350 infants on which we had data, 48.6% (170/350) were in the non-specific dilatation (NSD) category, and vesicoureteric reflux (VUR) was detected in 12%. Restricting investigations to those who had an APRPD > or =10 mm at >30 weeks of gestation could have reduced the number with NSD in the more recent cohort (26/115; 25%), but 25% of those with pelviureteric junction hold-up and 50% with VUR would have been missed. Significantly fewer patients in the more recent cohort underwent surgery (7 vs. 21%; p<0.001). There is a trend towards larger APRPDs on third trimester scans being associated with more significant pathology, but there is a lot of clinical overlap. The study highlights the need for cautious antenatal counselling combined with an assurance to prospective parents that postnatal investigations will be performed in a stepwise manner based on the initial postnatal ultrasound scan and clinical findings.

Late recurrence of symptomatic hydronephrosis in patients with prenatally detected hydronephrosis and spontaneous improvement

PURPOSE

Most prenatal hydronephrosis improves or resolves spontaneously with conservative treatment. However, late recurrence of prenatal hydronephrosis sometimes develops after improvement. To define the need for continuous observation after improvement of hydronephrosis, long-term followup was carried out in children with prenatally diagnosed hydronephrosis.

MATERIALS AND METHODS

We retrospectively evaluated 344 cases initially presenting between July 1991 and June 2004 with prenatally detected hydronephrosis that persisted postnatally. Subjects underwent periodic assessment of hydronephrosis using ultrasonography and diuretic renography. Indications for surgery were associated symptoms, enlarged renal pelvis, worsening hydronephrosis on sequential ultrasonography and decrease in differential renal function greater than 5%. Mean duration of followup was 10.1 years.

RESULTS

Of the 394 kidneys followed nonoperatively 4 (1%) displayed worsened hydronephrosis after spontaneous improvement. Initial grade of hydronephrosis was grade I in 1 patient, grade II in 1, grade III in 1 and grade IV in 1. On serial ultrasonographic followup hydronephrosis worsened to grade IV in 3 kidneys and to grade III in 1 kidney. Mean patient age at worsening of hydronephrosis was 40 months (range 22 to 60). All 4 patients presented with clinical symptoms. All patients who underwent pyeloplasty displayed no symptoms, and had improved hydronephrosis after pyeloplasty.

CONCLUSIONS

Prenatally detected hydronephrosis can worsen after spontaneous postnatal improvement. Long-term followup is not required after improvement of prenatal hydronephrosis. However, pediatric urologists need to tell the parents that the child should undergo ultrasonography if clinical symptoms develop.

Treatment and outcome of prenatally detected newborn hydronephrosis

OBJECTIVE

For neonates with antenatally diagnosed primary ureteropelvic junction (UPJ)-type hydronephrosis, to attempt to clarify and refine criteria for establishing optimal follow-up and treatment guidelines.

PATIENTS AND METHODS

A total of 162 newborns (228 hydronephrotic kidneys) with this condition were prospectively followed and treated by the same surgeon in 2001-2005 for a mean of 53 (13-72) months. Ultrasonography and diuretic renogram were used for diagnosis and follow up, and Onen's grading system to determine degree of hydronephrosis.

RESULTS

On first postnatal ultrasound, the severity of hydronephrosis was grade 1 in 152 kidneys (surgery, 0%), 2 in 41 (surgery, 19.5%), 3 in 19 (surgery, 42.1%), and 4 in 16 kidneys (surgery, 93.8%). All the grade 1 cases resolved spontaneously without renal deterioration (renal function >40%). Renal function ranged between 7% and 34% in grade 4 patients. Overall, 201 hydronephrotic kidneys (88.2%) resolved spontaneously, while 27 (11.8%) required pyeloplasty because of evidence of obstructive injury, including increased hydronephrosis in 14/27 (6/27 had less than 10% decrease in renal function), greater than 10% decrease of renal function in 9/27, and greater than 10% decrease of renal function as well as increased hydronephrosis in 4/27 patients (15%).

CONCLUSION

In most cases, neonatal hydronephrosis is a relatively benign condition that can be followed safely by an initial non-operative approach unless there is evidence of obstructive injury. A follow-up protocol that permits early identification of a limited number of kidneys that may develop signs of obstruction and require pyeloplasty is crucial for a favorable outcome in patients with primary UPJ-type hydronephrosis. Onen's hydronephrosis grading system promises an easier and more appropriate follow up and timely treatment for children with this condition. A sufficient follow-up interval, especially during the first 3 years of life, is essential to help prevent permanent loss of renal function in kidneys that do develop signs of obstruction.

The bear paw: a radiologic sign for congenital ureteropelvic junction obstruction

This article defines a new radiographic descriptor of high-grade hydronephrosis suggestive of ureteropelvic junction obstruction that is easily recognized by urologists and non-urologists alike. This is useful information for medical personnel participating in the management of children with hydronephrosis.

A new modification of dismembered pyeloplasty for primary ureteropelvic junction obstruction

AIM

To present the results of a new modification of dismembered pyeloplasty performed to prevent the occurrence of secondary obstruction.

METHODS

Modified dismembered pyeloplasty was performed in 35 children (age range 3 months to 16 years) who had unilateral ureteropelvic junction obstruction. In postoperative follow-up, presence of hydronephrosis on ultrasonography, differential renal function (DRF) and renal drainage half-time on technetium-99m diethylenetriaminepentaacetic acid (DTPA) renography were recorded and compared with preoperative data.

RESULTS

Mean anteroposterior renal pelvic diameter, mean preoperative DRF and radioisotope clearance half-time on DTPA renography of the affected kidneys were 61.4 mm, 38.6% and 34.3 min in children with prenatal hydronephrosis, and 67.5 mm, 37.6% and 39.4 min in children that presented with symptoms, respectively. After surgery, mean anteroposterior renal pelvic diameter, mean DRF and radioisotope clearance half-time on DTPA renography of the affected kidneys were 10.9 mm, 45.9% and 11.9 min in children with prenatal hydronephrosis, and 20 mm, 41.9% and 15.2 min in children that presented with symptoms, respectively. No failure was observed in any patient at an average follow-up of 26 months (range 1-5 years).

CONCLUSIONS

Open dismembered pyeloplasty is the treatment of choice for intrinsic ureteropelvic junction obstruction. The modification of dismembered pyeloplasty that we performed is an alternative for the prevention of secondary obstruction.

An alternative grading system to refine the criteria for severity of hydronephrosis and optimal treatment guidelines in neonates with primary UPJ-type hydronephrosis

OBJECTIVE

We present our alternative hydronephrosis grading system (AGS) in an attempt to establish optimal treatment guidelines, and clarify and refine the criteria for severity of hydronephrosis in neonates.

PATIENTS AND METHODS

A total of 162 newborns (228 affected kidneys) with antenatally diagnosed primary ureteropelvic junction-type hydronephrosis were prospectively followed and treated by the same surgeon for a mean of 46 (6-65) months. Ultrasonography and diuretic renogram were used for diagnosis and follow up. Society for Fetal Urology (SFU) grading system, anteroposterior diameter of renal pelvis (APDRP) and our AGS were used to determine the degree of hydronephrosis. AGS: 0, no hydronephrosis; 1, dilatation of renal pelvis alone; 2, plus caliceal dilatation; 3, plus <1/2 (mild-to-moderate) renal parenchymal loss; 4, plus >1/2 (severe) renal parenchymal loss (cyst-like kidney with no visually significant renal parenchyma).

RESULTS

On the first postnatal ultrasound, the severity of hydronephrosis was SFU< or =2 in 152 kidneys (surgery, 0%), SFU-3 in 41 kidneys (surgery, 19.5%) and SFU-4 in 35 kidneys (surgery, 68.6%). The follow up, treatment and outcome of SFU-1 and SFU-2 patients were similar; all resolved spontaneously without renal deterioration (renal function >40%). Renal function ranged between 7% and 39% in SFU-4 patients. Intrarenal pelvis was found in one patient with an APDRP of <15 mm, seven patients of 16-30 mm, and five patients of >30 mm. Overall, 201 hydronephrotic kidneys (88.2%) resolved spontaneously while 27 (11.8%) required pyeloplasty.

CONCLUSION

Neither an SFU grading system nor measurement of APDRP is the gold standard in determining the severity of hydronephrosis. Both methods may fail, particularly in children with intrarenal pelvis configuration or SFU-4 hydronephrosis. Our AGS promises easier follow up and more timely treatment.

Delayed decrease in differential renal function after successful pyeloplasty in children with unilateral antenatally detected hydronephrosis

AIM

The aim of this study was to evaluate functional outcome of congenital hydronephrotic kidney.

METHODS

The records of consecutive children who underwent pyeloplasty for unilateral prenatally detected ureteropelvic junction obstruction were reviewed. Renal function was assessed renographically before and after surgery. Mean follow-up period was 100 months.

RESULTS

Sufficient pre- and postoperative data were available for 60 children. Differential renal function (DRF) improved in 14 (23%) and decreased in nine (15%) of 60 patients in the early postoperative period. DRF improved in seven (18%) and decreased in 13 (34%) of 38 patients at the end of follow-up. Five of 14 patients with increased DRF at early postoperative scan returned to the preoperative level at the end of follow-up. No patients with decreased DRF at early postoperative scan showed any recovery in DRF and progressive decrease was seen in four of nine children.

CONCLUSIONS

The DRF was not stable in some patients after successful pyeloplasty. In some patients impairment of renal function came to be apparent with time. Improvement of DRF may be a transient phenomenon seen in the early postoperative period. To avoid overestimation of functional recovery, long-term follow-up with delayed renographic evaluation is recommended.

Magnetic Resonance Urographic Parameters for Predicting the Need for Pyeloplasty in Infants With Prenatally Diagnosed Severe Hydronephrosis

PURPOSE

Treatment in infants with prenatally diagnosed, severe hydronephrosis remains controversial. We measured anatomical parameters using magnetic resonance urography to create a pelvic index ratio, which we correlated with outcome to assess its value.

MATERIALS AND METHODS

We reviewed 35 cases of prenatally diagnosed severe hydronephrosis, including grade III in 19 and grade IV in 16. By 6 weeks after birth all patients had undergone repeat ultrasonography, diuretic renography and magnetic resonance urography. Magnetic resonance urography was used to measure the distance (D) from the bottom of the lowest renal calyx to the ureteropelvic junction and the total longitudinal length (L) of the caliceal system. The pelvic index ratio, defined as D/L, assesses the level at which the ureter inserts into the renal pelvis.

RESULTS

All cases were initially managed conservatively. Pyeloplasty was required in 16 kidneys (mean patient age +/- SD 7.5 +/- 3.9 months) because of deterioration in renal function. All patients were well at a mean followup of 3.8 years. The remaining 19 cases continued to be managed conservatively. By a mean of 5.4 years spontaneous resolution of prenatally diagnosed severe hydronephrosis had occurred in 7 of 19 cases, while 12 were downgraded to grades I-II. The mean pelvic index ratio in surgical cases was 0.26 +/- 0.13 and in nonsurgical cases it was 0.12 +/- 0.11, indicating that ureters inserted significantly higher in surgical cases (p = 0.0012). Of 9 kidneys with a pelvic index ratio of greater than 0.3 pyeloplasty was required in 8, while 10 of 12 with a pelvic index ratio of less than 0.1 were managed conservatively.

CONCLUSIONS

Pyeloplasty is likely to be required if the pelvic index ratio is greater than 0.3 and conservative management is likely to succeed if the ratio is less than 0.1. The pelvic index ratio can be calculated easily even in the neonatal period. It appears to be prognostic for pyeloplasty in cases of prenatally diagnosed, severe hydronephrosis.

Diagnostic difficulties in children with coexisting pelvi-ureteric and vesico-ureteric junction obstruction

OBJECTIVE

To assess the diagnosis of children with coexisting pelvi-ureteric junction (PUJ) and vesico-ureteric junction (VUJ) obstruction, and the management of such patients, as having these two anomalies in the same ureter creates serious diagnostic difficulties, but any delay in diagnosis might cause a deterioration of renal function and affect the success of surgery to correct either anomaly.

PATIENTS AND METHODS

We assessed the diagnostic difficulties and approach to 14 patients with coexistent PUJ and VUJ obstruction, who were treated surgically in our clinic between 1994 and 2005; we also review related published reports in English.

RESULTS

Surgery was used in all 14 patients over the 11-year period; only five patients had an accurate diagnosis before surgery. Six patients were diagnosed with uroradiological techniques immediately after pyeloplasty; three were diagnosed on investigating an associated anomaly later.

CONCLUSION

In children with coexisting PUJ and VUJ obstruction there are serious diagnostic problems; to prevent any deterioration in renal function due to obstruction, these anomalies require early diagnosis and treatment. For an early and accurate diagnosis, the coexistence of these two anomalies in the same ureter should be considered.