Metal stent for the ureteral stricture after surgery and/or radiation treatment for malignancy.

BACKGROUND: To assess the efficacy and safety of self-expanding metal ureteral stent for the stricture following surgery and/or radiation for malignancy. METHODS: We performed 36 metal ureteral stent insertion procedures (32 patients) between May 2019 and June 2020. The main inclusion criterion was the patients with ureteral stricture due to surgery and/or radiation treatment for malignancy. The diagnosis of stricture was ascertained by history and radiographic imaging. The etiologies underlying the strictures were: surgery and/or radiation therapy for cervical and rectal cancer, surgery for ovarian cancer. The primary outcome was the stent patency rate, and the secondary outcomes were the postoperative complications and glomerular filtration rate (GFR). Stent patency was defined as stent in situ without evident migration, unanticipated stent exchange or recurrent ureteral obstruction. Cost analysis was calculated from stent cost, anesthesia cost and operating room fee. RESULTS: The pre-metallic stent GFR was 22.53 ± 6.55 mL/min/1.73 m2. Eight patients were on double-J stents before insertion of metallic stents. The total annual cost of per patient in our study was $10,600.2 US dollars (range $9394.4-$33,527.4 US dollars). During a median follow-up time of 16 months (range 8-21 months), 27 cases (31 sides, 84%) remained stent patency. Twelve patients died from their primary malignancy carrying a patency stent. Stent migration was observed in 4 patients within 10 months after insertion. Ectopic stents were endoscopically removed and replaced successfully. Three stents were occluded, and no encrustation was seen in our study. Three and four patients had postoperative fever and gross hematuria, respectively. Infection was observed in 2 cases, mandating antibiotics therapy. In addition, postoperative volume of hydronephrosis postoperatively was significantly reduced compared with preoperation (54.18 ± 15.42 vs 23.92 ± 8.3, P = 0.019). However, no statistically significant differences regarding GFR, creatinine levels, blood urea nitrogen and hemoglobin existed between preoperation and last follow-up. CONCLUSIONS: The current study demonstrated that metal ureteral stent is effective and safe in the treatment of stricture following surgery and/or radiation therapy for malignant cancer. Patients hydronephrosis could be improved by the stent placement.

Comparison of Conservative and Surgical Treatments in Symptomatic Pregnancy Hydronephrosis.

OBJECTIVES: This study aimed to evaluate the factors affecting the treatment choice in pregnant women with symptomatic hydronephrosis. METHODS: Hospital records of pregnant women who visited our clinic due to symptomatic hydronephrosis between December 2010 and December 2020 were analysed retrospectively. Patients were divided into 2 groups: conservative and surgical (JJ stent) treatment groups. Age, gestational week, primipara, trimester, visual analogue scale (VAS), and preterm birth rates as well as clinical, laboratory, and ultrasonography findings were compared between the groups. RESULTS: The study included 227 pregnant women (conservative treatment group, 133; JJ stent group, 94). Age, gestational week, primipara, trimester, hydronephrosis side, fever, pyelonephritis, pyuria, preterm labour and abortion, as well as blood urea nitrogen, creatinine, C-reactive protein, and white blood cell levels did not differ significantly between the groups (p > 0.05). In the JJ stent group, VAS, creatinine value, culture positivity rate, degree of hydronephrosis, and renal pelvis anterior-posterior (AP) diameter were significantly higher than those in the conservative treatment group (p < 0.05). The cut-off value for renal pelvis AP diameter was 16.5 mm in the first 2 trimesters and 27.5 mm in the third trimester. CONCLUSIONS: Surgical treatment should not be delayed in pregnant women who do not respond to conservative treatment and have impaired renal function and grade 3-4 hydronephrosis. Early surgical intervention is necessary in patients with a renal pelvis AP diameter of >16.5 mm in the first 2 trimesters and >27.5 in the third trimester.

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT.

BACKGROUND: It is a challenging problem to differentiate obstructive hydronephrosis from noninvasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in the quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs. METHODS: In this study, a perfusion pig model was constructed by constant pressure perfusion testing of the renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create a state of no obstruction and acute obstruction of the lower part of the left ureter. After successful modelling, continuous dynamic volume scanning of the bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analysed. No obstruction or acute obstruction of the lower part of the left ureter was observed. Pump functions of the renal pelvis and part of the upper ureter were determined. RESULTS: The results showed that after LUUT fistulostomy, the time difference between the average UUT volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased with mild obstruction and decreased with severe obstruction, and there was a significant difference between the left and right sides. CONCLUSION: The continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function datasets of UUT in pigs with acute lower ureteral obstruction.

Timing urinary tract reconstruction in rats to avoid hydronephrosis and fibrosis in the transplanted fetal metanephros as assessed using imaging.

Chronic kidney disease leads to high morbidity rates among humans. Kidney transplantation is often necessary for severe symptoms; however, options for new curative treatments are desired because of donor shortage. For example, it has been established that the kidneys can efficiently generate urine after transplantation of the metanephros, ureter, and bladder as a group. After transplantation, the urine can indirectly flow into the recipient's bladder using a stepwise peristaltic ureter system method where the anastomosis is created via the recipient's ureter for urinary tract reconstruction. However, the growth of the regenerated metanephros varies significantly, whereas the time window for successful completion of the stepwise peristaltic ureter system that does not cause hydronephrosis of the metanephros with bladder (ureter) is quite narrow. Therefore, this study was conducted to periodically and noninvasively evaluate the growth of the transplanted metanephros, ureter, and bladder in rats through computed tomography and ultrasonography. The ultrasonographic findings highly correlated to the computed tomography findings and clearly showed the metanephros and bladder. We found that the degree of growth of the metanephros and the bladder after transplantation differed in each case. Most of the rats were ready for urinary tract reconstruction within 21 days after transplantation. Optimizing the urinary tract reconstruction using ultrasonography allowed for interventions to reduce long-term tubular dilation of the metanephros due to inhibited overdilation of the fetal bladder, thereby decreasing the fibrosis caused possibly by transforming growth factor-ß1. These results may be significantly related to the long-term maturation of the fetal metanephros and can provide new insights into the physiology of transplant regeneration of the metanephros in higher animals. Thus, this study contributes to the evidence base for the possibility of kidney regeneration in human clinical trials.

Rats with congenital hydronephrosis show increased susceptibility to renal ischemia-reperfusion injury.

Many drug candidates have shown significant renoprotective effects in preclinical models; however, there is no clinically used effective pharmacotherapy for acute kidney injury. The failure to translate from bench to bedside could be due to misleading results from experimental animals with undetected congenital kidney defects. This study was performed to assess the effects of congenital hydronephrosis on the functional capacity of tubular renal transporters as well as kidney sensitivity to ischemia-reperfusion (I-R)-induced injury in male Wistar rats. Ultrasonography was used to distinguish healthy control rats from rats with hydronephrosis. L-carnitine or furosemide was administered, and serial blood samples were collected and analyzed to assess the effects of hydronephrosis on the pharmacokinetic parameters. Renal injury was induced by clamping the renal pedicles of both kidneys for 30 min with subsequent 24 hr reperfusion. The prevalence of hydronephrosis reached ~30%. The plasma concentrations after administration of L-carnitine or furosemide were similar in both groups. I-R induced more pronounced renal injury in the hydronephrotic rats than the control rats, which was evident by a significantly higher kidney injury molecule-1 concentration and lower creatinine concentration in the urine of the hydronephrotic rats than the control rats. After I-R, the gene expression levels of renal injury markers were significantly higher in the hydronephrotic kidneys than in the kidneys of control group animals. In conclusion, our results demonstrate that hydronephrotic kidneys are more susceptible to I-R-induced damage than healthy kidneys. Unilateral hydronephrosis does not affect the pharmacokinetics of substances secreted or absorbed in the renal tubules.

Non-invasive evaluation of obstruction after ureteroscopic stone removal: Role of renal resistive index assessment.

OBJECTIVES: The aim of this study is to evaluate prediction of postoperative ureteral obstruction needing ureteral stent insertion by evaluating the resistive index (RI) values and the grade of hydronephrosis. MATERIAL AND METHODS: A total of 66 adult patients undergoing stentless endoscopic ureteral stone treatment (URS) between January 2018 and January 2019 were included in this prospective study. Preoperative patient and stone characteristics were noted. All patients were evaluated with renal Doppler ultrasonography study to assess degree of hydronephrosis and RI values. A renal Doppler ultrasonography was repeated at postoperative 1st, 3rd and 7th days. Changes in both RI and hydronephrosis levels before and after the procedures were noted. On the postoperative 7th day, patients were divided into two groups including obstructive and non-obstructive cases according to RI values assessed where a RI value of 0.7 was accepted as the cut-off for obstruction. The preoperative and perioperative characteristics of both groups were evaluated in a comparative manner. RESULTS: The mean patient age was 43.6 ± 1.72 years. Significant improvements were noted in RI and grade of hydronephrosis after the operation. The grade of hydronephrosis and RI values were found to improve more significantly on postoperative 3rd day when compared to the postoperative 7th day (p < 0.01 and p < 0.01). A significant correlation was detected between the grade of hydronephrosis (>grade 2) and obstructive RI values (> 0.7) in each postoperative visits (p: 0.001). RI values (> 0.7) at postoperative seventh days were correlated with larger mean stone size, increased ureteral wall thickness, increased diameter of the ureter proximal to the stone, and longer duration of the operation. Preoperative high-grade hydronephrosis indicated obstructive RI values at postoperative seventh day (p = 0.001) Conclusion: Changes in RI values on Doppler sonography and the grade of hydronephrosis may be a guiding parameter in assessing postoperative ureteral obstruction.

Is isolated bladder outlet obstruction associated with hydronephrosis? A database analysis.

AIMS: To examine whether isolated bladder outlet obstruction in the absence of associated lower urinary tract abnormality results in hydronephrosis. Isolated obstruction causes a brief rise in bladder pressure that might not trigger hydronephrosis. METHODS: Data included adult men who underwent urodynamics for refractory non-neurogenic lower tract symptoms between 2011 and 2020. International Continence Society indices for obstruction (bladder outlet obstruction index [BOOI] ≥ 40) and underactivity (bladder contractility index [BCI] < 100) were calculated. Storage abnormality was defined as detrusor overactivity (DO) or poor compliance (<20 ml/cm H2 0). Isolated obstruction was defined as BOOI ≥ 40, BCI ≥ 100 and no storage abnormality. Nonparametric tests using R program (3.5.0) applied (p < .05 significant). Logistic regression analyses were performed to study the relationships of hydronephrosis with lower urinary tract function. RESULTS: A total 1596 men (range, 18-91 years; median, 51.0 years; Q3, 64.0 years; Q1, 34.0 years) were eligible. Hydronephrosis was noted in 274 (17.2%). A total of 45.4% were obstructed, 52.3% were underactive and 41.7% had storage abnormality. Storage abnormality (odds ratios [OR], 2.05; 95% confidence interval [CI]: 1.56, 2.69; p < .001) and bladder contractility (OR, 1.68; 95% CI, 1.25-2.26; p < .001) but not obstruction (OR, 1.07; 95% CI, 0.80-1.44; p = .634) was associated with hydronephrosis. Of eight possible combinations, men with BOO ≥ 40, BCI ≥ 100 and storage abnormality had highest probability of hydronephrosis (OR, 0.29; 95% CI, 0.24-0.33). Subanalysis showed that poor compliance (OR, 3.39; 95% CI, 2.49-4.60; p < .001) but not DO was associated with hydronephrosis. Younger age and higher postvoid residual urine were also associated with hydronephrosis. CONCLUSIONS: In adult men with refractory non-neurogenic lower urinary tract symptoms, isolated bladder outlet obstruction is not associated with hydronephrosis.

In utero myelomeningocele repair: The natural history of patients with incontinent pattern (sphincteric deficiency: leakage below 40 CMH20).

INTRODUCTION: Since 2011 we have been following prospectively myelomeningocele patients treated in utero with particular interest to patients with sphincter weakness/deficiency. We investigated the changes of bladder pattern and upper urinary tract with time in children who underwent in utero repair and had low-pressure incontinence based on urodynamic evaluation (UE). MATERIALS AND METHODS: From the 120 patients in our database, 117 had at least one UE. Of these, 30 were classified as incontinent when leaking at low pressure (<40 cmH20). We reviewed clinical evaluation, urinary tract ultrasound, voiding cystourethrography (VCUG), and other UE parameters at first and last evaluation. RESULTS: We found 30 cases (25.64%). Mean age at initial evaluation was 4.97 months followed by UE done initially at mean age of 5.73 months. Follow-up was 28.4 months. Febrile urinary tract infection has been found in four patients (13.3%), hydronephrosis in four patients, and bladder neck thickening in three (10%). The VCUG showed vesicoureteral reflux in three cases (3/27, 11.1%). A total of 90% of patients had detrusor overactivity with mean maximum detrusor pressure (33.37 cmH20). Only 16.67% of patients showed normal bladder capacity. From the 30 patients, 23 had at least two UE. We noticed a change of bladder pattern as follows: six patients became of high-risk pattern, five normal, and two with underactive bladder pattern. The average interval between the first and last UE was 25.5 months (median: 15 months). CONCLUSION: We concluded that 43.47% of patients with low DLPP have kept the incontinent pattern. If the initial LPP was below 30 cmH20, 70% remained with the incontinet pattern.

An overview of hydronephrosis in adults.

Hydronephrosis is diagnosed more often with the increased availability of computed tomography and ultrasound scanning. Hydronephrosis is an important consideration in patients with abdominal or pelvic pathology as progressive dilation of the upper urinary tract can lead to acute kidney injury and, if not corrected, permanent nephron loss. This article explores how to approach an adult patient with hydronephrosis, encompassing aetiology, clinical presentation, diagnosis and management.

Effect of Early Oxybutynin Treatment on Posterior Urethral Valve Outcomes in Infants: A Randomized Controlled Trial.

PURPOSE: We studied the effect of oxybutynin on bladder and upper urinary tract outcomes in infants following posterior urethral valve ablation. MATERIALS AND METHODS: Patients younger than 12 months old who had undergone primary endoscopic valve ablation for posterior urethral valves were screened for eligibility. Patients who had undergone urinary diversion or had other conditions that could affect lower urinary tract function were excluded. Study patients were randomized to either oxybutynin (0.2 mg/kg 3 times daily) until toilet training or active observation. The study end points were serum creatinine, estimated glomerular filtration rate, hydronephrosis improvement, vesicoureteral reflux resolution, febrile urinary tract infection and toilet training. RESULTS: A total of 49 infants (24 receiving oxybutynin and 25 undergoing observation) were enrolled between December 2013 and September 2015 and completed at least 1 year of followup. Oxybutynin was discontinued before toilet training in 5 patients due to facial flushing in 2, bladder and upper tract dilatation in 2, and cognitive changes in 1. After a median followup of 44.2 months (range 12 to 57.6) median serum creatinine and estimated glomerular filtration rate were not significantly different between the groups (p=0.823 and p=0.722, respectively). Renal units in the oxybutynin group had a greater likelihood of hydronephrosis improvement (61.9% vs 34.8%, p=0.011) and resolution of vesicoureteral reflux (62.5% vs 25%, p=0.023). Febrile urinary tract infection (29.2% vs 40%, p=0.404), completion of toilet training (70.8% vs 76%, p=0.748) and age at toilet training (p=0.247) did not differ significantly between the oxybutynin and observation groups. CONCLUSIONS: Oxybutynin enhances hydronephrosis improvement and vesicoureteral reflux resolution following primary endoscopic valve ablation in infants but periodic monitoring is warranted.

Prognostic value of preoperative hydronephrosis in patients with bladder cancer undergoing radical cystectomy: A meta-analysis.

BACKGROUND: Hydronephrosis is a common finding in patients with bladder cancer. The aim of the study was to appraise the prognostic value of preoperative hydronephrosis in bladder cancer patients undergoing radical cystectomy. METHODS: We conducted a literature search using PubMed and Embase databases in Aug 2018. Summary hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using fixed-effect or random-effects models. The primary endpoint was overall survival (OS). Secondary endpoints were cancer-specific survival (CSS) and recurrence-free survival (RFS). RESULTS: Overall, 13 studies published between 2008 and 2018 including 4,820 patients were selected for the meta-analysis. The age of bladder cancer patients ranged from 27 to 90.4 years, and the overall proportion of males was 72.5%. Preoperative hydronephrosis was reported in 27.4% of patients. The pooled HR was statistically significant for OS (HR, 1.36; 95% CI [1.20-1.55]) and CSS (HR, 1.64; 95% CI [1.33-2.02]), with no heterogeneity among the enrolled studies. Patients with bilateral hydronephrosis showed a poorer CSS compared to those with no hydronephrosis (HR 5.43, 95% CI [3.14-9.40]). However, there was no difference in CSS between no hydronephrosis and unilateral hydronephrosis groups (HR 1.35, 95% CI [0.84-2.14]). Despite a tendency towards poorer RFS (HR, 1.27; 95% CI [0.96-1.96]), the results demonstrated no significant association between presence of preoperative hydronephrosis and RFS after radical cystectomy. CONCLUSION: This meta-analysis indicates that preoperative hydronephrosis is significantly associated with poorer OS and CSS after radical cystectomy for patients with bladder cancer. Preoperative hydronephrosis has a stronger effect on CSS in patients with bilateral hydronephrosis. The presence of preoperative hydronephrosis not only predicts prognosis, but may also help to identify patients who benefit the most from neoadjuvant chemotherapy.

Unusual cause of dysphagia.

In this case, we describe a unique case of large renal hydronephrosis in a 79-year-old Indian male patient who had initially presented with 3 months of progressive dysphagia and loss of weight. His dysphagia was initially thought to be related to the atypical diagnosis of achalasia and was being considered for an elective laparoscopic Heller myotomy. On performing CT of the abdomen, a large renal mass was discovered. However, predicament remained regarding the exact aetiology of this renal mass. This case highlights a tremendously intriguing case of dysphagia with an underlying aetiology that has not been reported elsewhere previously.

Diagnosis of an Acute Lobar Nephronia in the Emergency Department Using POINT-OF-CARE Ultrasound.

BACKGROUND: Over the past decade, point-of-care ultrasound (POCUS) has been performed increasingly in pediatric emergency medicine for a variety of indications. POCUS is a focused, limited, goal-directed examination at the bedside performed and interpreted by a physician trained in POCUS with the purpose of answering a specific question. Applying POCUS for immediate evaluation of specific emergent complaints may allow for faster and safer management of ill patients in the pediatric emergency department (ED). CASE REPORT: A 5-year-old female presented to the pediatric ED with fever, vomiting, and back pain. Based on the real-time gray scale and color Doppler POCUS findings, a diagnosis of an acute lobar nephronia (ALN) was made by a pediatric emergency physician and the patient was admitted to the hospital before laboratory and urinalysis findings were resulted. This case report illustrates how POCUS and knowledge of the sonographic characteristics of an ALN were beneficial for shortening the time to decision for admission, rapidly ruling out hydronephrosis (which may have required other interventions), and conveying important information to the admitting team. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Performing a kidney POCUS and knowing the sonographic characteristics of an ALN can assist in its diagnosis, especially in patients where pyuria is absent. In addition, performing a kidney POCUS in patients with a suspected upper urinary tract infection may shorten the time to decision for admission and improve communication with the pediatric admitting resident regarding diagnosis and indication.

The Accuracy of Renal Function Measurements in Obstructive Hydronephrosis Using Dynamic Contrast-Enhanced MR Renography.

OBJECTIVE. The objective of our study was to assess the accuracy of glomerular filtration rate (GFR) evaluation in patients with obstructive hydronephrosis using dynamic contrast-enhanced MR renography (DCE-MRR). MATERIALS AND METHODS. A group of 28 adult volunteers were enrolled in this study: 13 without hydronephrosis, eight with low-grade hydronephrosis, and seven with high-grade hydronephrosis. The GFR obtained from DCE-MRR (GFRMRR) and the GFR obtained from renal scintigraphy (GFRRS) were compared with the reference GFR (GFRRef) acquired using the two plasma sample method. The correlation and agreement between GFRMRR and GFRRef, GFRRS and GFRRef, and single-kidney GFRMRR (skGFRMRR) and single-kidney GFRRS (skGFRRS) were assessed. The interrater reliability of DCE-MRR and the interrater reliability of renal scintigraphy (RS) were measured. RESULTS. Both GFRMRR and GFRRS correlated well with GFRRef. In patients with hydronephrosis, DCE-MRR and RS overestimated GFR by 12.8 ± 13.9 mL/min (mean ± SD) and 11.5 ± 12.3 mL/min, respectively. The skGFRRS was higher than skGFRMRR by 5.7 ± 3.8 mL/min in high-grade hydronephrotic kidneys (p = 0.004). Good interrater reliability was observed for skGFRMRR (intraclass correlation coefficient [ICC] = 0.82-0.92) and skGFRRS (ICC = 0.79-0.90) for both nonhydronephrotic kidneys and hydronephrotic kidneys. The overall mean SDs of repeated measurements from three investigators were 4.0 and 3.8 mL/min for skGFRMRR and skGFRRS, respectively. CONCLUSION. Both DCE-MRR and RS tend to overestimate GFR in patients with hydronephrosis. RS-derived skGFR is slightly higher than that of DCE-MRR in kidneys with high-grade hydronephrosis. DCE-MRR is comparable to RS and may serve as an alternative noninvasive method for GFR measurement.

Value of supranormal function on 99m Tc-mercaptoacetyltriglycine renal scan in paediatric patients with obstructive hydronephrosis.

OBJECTIVES: To study related factors and clinical significance of supranormal function in paediatric patients with pelvi-ureteric junction obstruction, and to predict which factors cause renal function overestimation. PATIENTS AND METHODS: Patients who underwent pyeloplasty from 2012 to 2017 were prospectively collected. Variables were compared between patients with and without supranormal function on 99m Tc-mercaptoacetyltriglycine renal scan (supranormal defined as differential renal function [DRF] ≥55%). Univariate, multivariate logistic and linear regressions analyses were performed. RESULTS: Of 100 patients, 18 were excluded because of comorbidities. Nine patients (11.5%) showed preoperative supranormal function. The preoperative anteroposterior pelvic diameter (APD; 24 mm vs 35 mm, P = 0.026) and the ratio between preoperative pelvic and kidney volumes (0.2 vs 0.6, P = 0.003) were higher in supranormal kidneys. For each unit increase in the preoperative ratio between pelvic and kidney volumes, the risk of supranormal function rose 3.23-times (95% confidence interval [CI] 1.051-9.955). A preoperative APD ≥30 mm was a reliable predictor of supranormal function (area under the curve 0.804, 95% CI 0.707-0.902), with 88.9% sensitivity. Patients with either preoperative supranormal function or preoperative APD ≥30 mm had a greater reduction in renal function after pyeloplasty. CONCLUSION: Supranormal function is related to large hydronephrosis where geometrical features are modified. A preoperative APD ≥30 mm is a reliable predictive factor of supranormal function. Preoperative renal function is overestimated either in supranormal patients or severe hydronephrotic kidneys. DRF should be interpreted with caution in kidneys with large hydronephrosis with or without supranormal function. Surgical indication should not entirely rely upon DRF.

Natural course of isolated mild congenital hydronephrosis: A 2-year prospective study at a single center in Japan.

OBJECTIVES: To determine a follow-up plan for mild congenital hydronephrosis in Japanese individuals. METHODS: Neonates at Kansai Medical University Hospital (Hirakata, Osaka, Japan) who were diagnosed with mild congenital hydronephrosis - defined as a Society for Fetal Urology grade 1 or 2 - at 1-month old by abdominal ultrasonography between 2014 and 2016 were enrolled. These patients were encouraged to undergo repeated abdominal ultrasonography for 2 years every 3 months to investigate the course of congenital hydronephrosis. RESULTS: Among 1009 neonates, congenital hydronephrosis was detected in 118 affected renal units of 100 (9.9%) patients. According to the definition of the Society for Fetal Urology, 118 affected renal units were graded as grade 1 in 87 (74%), grade 2 in 30 (25%), grade 3 in one (1%) and grade 4 in 0 units. Among them, 117 affected renal units of mild congenital hydronephrosis comprising grades 1 and 2 were subjected to ultrasonographic evaluation to monitor the natural course. The rates of resolution at 7, 10, 13, 16, 19, 22 and 25 months after birth in Society for Fetal Urology grades 1 and 2 cases were 60% and 8%, 77% and 19%, 90% and 32%, 92% and 40%, 95% and 52%, 96% and 56%, and 99% and 60%, respectively. CONCLUSIONS: Grade 1 congenital hydronephrosis does not need to be followed up, because it mostly shows spontaneous resolution by 2 years of follow up without any complications. However, ultrasonographic examinations at 1-year intervals for grade 2 congenital hydronephrosis are recommended to determine the subsequent follow-up plan of patients.

Diuresis renography in the evaluation and management of pediatric hydronephrosis: What have we learned?

Diuresis renography (DR) is widely used in the evaluation of hydronephrosis and hydroureter in infants and children. The goal of this provocative nuclear imaging examination should be to detect the hydronephrotic kidneys at risk for loss of function and development of pain, hematuria, and urinary tract infection. The reliability of DR is dependent on the acquisition and processing of the data as well as interpretation and utilization of the results. In this review, the key concepts of standardized DR and pitfalls to avoid are highlighted.