Primary non-refluxing megaureter: Natural history, follow-up and treatment.

Primary non-refluxing megaureter (PMU) is a congenital dilation of the ureter which is not related to vesicoureteral reflux, duplicated collecting systems, ureterocele, ectopic ureter, or posterior urethral valves and accounts for 5 to 10% of all prenatal hydronephrosis (HN) cases. The etiology is a dysfunction or stenosis of the distal ureter. Most often PMU remains asymptomatic with spontaneous resolution allowing for non-operative management. Nevertheless, in selective cases such as the development of febrile urinary tract infections, worsening of the ureteral dilatation, or reduction in relative renal function, surgery should be considered. CONCLUSION: Ureteral replantation with excision of the dysfunctional ureteral segment and often ureteral tapering is the gold-standard procedure for PMU, although endoscopic treatment has been shown to have a fair success rate in many studies. In this review, we discuss the natural history, follow-up, and treatment of PMU. WHAT IS KNOWN: • PMU is the result of an atonic or stenotic segment of the distal ureter, resulting in congenital dilation of the ureter, and is frequently diagnosed on routine antenatal ultrasound. WHAT IS NEW: • Most often, PMU remains asymptomatic and clinically stable, allowing for non-operative management. • Nevertheless, since symptoms can appear even after years of observation, long-term ultrasound follow-up is recommended, even up to young adulthood, if hydroureteronephrosis persists. • Ureteral replantation is the gold standard in case surgery is needed. In selected cases, however, HPBD could be a reasonable alternative.

[Comparison of safety and effectiveness of active migration technique and in situ lithotripsy technique in the treatment of 1-2 cm upper ureteral calculi by flexible ure-teroscopy].

OBJECTIVE: To compare the safety and effectiveness of active migration technique and in situ lithotripsy technique in the treatment of 1-2 cm upper ureteral calculi by retrograde flexible ureteroscopy. METHODS: A total of 90 patients with 1-2 cm upper ureteral calculi treated in the urology department of Beijing Friendship Hospital from August 2018 to August 2020 were selected as the subjects. The patients were divided into two groups using random number table: 45 patients in group A were treated with in situ lithotripsy and 45 patients in group B were treated with active migration technique. The active migration technique was to reposition the stones in the renal calyces convenient for lithotripsy with the help of body position change, water flow scouring, laser impact or basket displacement, and then conduct laser lithotripsy and stone extraction. The data of the patients before and after operation were collected and statistically analyzed. RESULTS: The age of the patients in group A was (51.6±14.1) years, including 34 males and 11 females. The stone diameter was (1.48±0.24) cm, and the stone density was (897.8±175.9) Hu. The stones were located on the left in 26 cases and on the right in 19 cases. There were 8 cases with no hydronephrosis, 20 cases with grade Ⅰ hydronephrosis, 11 cases with grade Ⅱ hydronephrosis, and 6 cases with grade Ⅲ hydronephrosis. The age of the patients in group B was (51.8±13.7) years, including 30 males and 15 females. The stone diameter was (1.52±0.22) cm, and the stone density was (964.6±214.2) Hu. The stones were located on the left in 22 cases and on the right in 23 cases. There were 10 cases with no hydronephrosis, 23 cases with grade Ⅰ hydronephrosis, 8 cases with grade Ⅱ hydronephrosis, and 4 cases with grade Ⅲ hydronephrosis. There was no significant diffe-rence in general parameters and stone indexes between the two groups. The operation time of group A was (67.1±16.9) min and the lithotripsy time was (38.0±13.2) min. The operation time of group B was (72.2±14.8) min and the lithotripsy time was (40.6±12.6) min. There was no significant difference between the two groups. Four weeks after operation, the stone-free rate in group A was 86.7%, and in group B was 97.8%. There was no significant difference between the two groups. In terms of complications, 25 cases of hematuria, 16 cases of pain, 10 cases of bladder spasm and 4 cases of mild fever occurred in group A. There were 22 cases of hematuria, 13 cases of pain, 12 cases of bladder spasm and 2 cases of mild fever in group B. There was no significant difference between the two groups. CONCLUSION: Active migration technique is safe and effective in the treatment of 1-2 cm upper ureteral calculi.

Wunderlich syndrome secondary to ureteropelvic junction obstruction.

Wunderlich syndrome (WS) is defined as a rare spontaneous renal hemorrhage. It mostly occurs with concomitant diseases without trauma. It usually presents with the Lenk triad and is diagnosed in emergency departments with the effective use of advanced imaging modalities such as ultrasonography, computerized tomography, or magnetic resonance imaging scanning. In the management of WS, conservative treatment, interventional radiology, or surgical procedures are decided according to the patient's condition and treated appropriately. Conservative follow-up and treatment should be considered in patients whose diagnosis is stable. If diagnosed late, the progression can be life-threatening. As an interesting case of WS, a 19-year-old patient was presented with hydronephrosis due to ure-teropelvic junction obstruction. Spontaneous renal hemorrhage without a history of trauma is presented. The patient, who presented to the emergency department with the sudden onset of flank pain, vomiting, and macroscopic hematuria was imaged by computed tomography. The patient could be followed and treated conservatively for the first 3 days, and on the 4th day, his general condition deteriorated, and he underwent selective angioembolization and then laparoscopic nephrectomy. WS is a serious, life-threatening emer-gency, even in young patients with benign conditions. Early diagnosis is mandatory. Delays in diagnosis and non-energetic approaches can lead to life-threatening situations. In hemodynamically unstable non-malignant cases, the decision for immediate treatment, such as angioembolization and surgery, should be taken without hesitation.

How well do ESWL nomograms predict treatment success in pediatric patients?

OBJECTIVE: To study was to identify the variables that influence the outcomes of pediatric SWL patients in our clinic and to compare our findings to previously published nomograms. METHODS: All children who underwent SWL at a single center between 2005 and 2020 were included in this retrospective study. Depending upon the age and mental state of the children, SWL procedures were performed with or without anesthesia. Data from the hospital information system were obtained on patient characteristics, metabolic evaluation, imaging, SWL details, and post-procedure results, and their correlation with the Onal and Dogan nomograms was evaluated. RESULTS: The present study included 112 pediatric patients in total. The average age was 8.22 ± 4.9 (83.3 ± 58.1 months, 4 months-16 years), and the median stone size was 9.5 ± 3.2 mm (4-20 mm). Even though there was quite a significant positive correlation between age and the number of shots and the intensity of shots (intensity and number of shots increased with increasing age), there was no statistical difference in the number of sessions and stone-free rates. The number of shots and sessions was significantly lower in patients with hydronephrosis (N = 70) than in those without (N = 42) (p < 0.001). When the stone-free rates of patients without and with hydronephrosis were compared, it was discovered that they were 69.05% and 92.86%, respectively, which was statistically significant (p < 0.01). CONCLUSIONS: It is believed that the nomograms developed for SWL in pediatric patients should be reviewed, and larger, prospective studies should be conducted.

Subcapsular renal haematoma after ureteroscopic lithotripsy: a single-centre, retrospective study in China.

OBJECTIVES: To investigate the incidence, predisposing factors, diagnosis and management of subcapsular renal haematoma (SRH) after ureteroscopic lithotripsy (URSL). DESIGN: Retrospective observational study. SETTING: Shandong Provincial Hospital, a 4500-bed tertiary hospital in China. PARTICIPANTS: The data from 1535 consecutive patients treated with URSL (including rigid URSL and flexible URSL) between January 2015 and October 2020 were retrospectively analysed. MAIN OUTCOME MEASURES: SRH after URSL confirmed via CT. The characteristics, operative data and outcomes of these patients were documented and compared. RESULTS: Six patients were confirmed to have an SRH after URSL on CT. The total incidence of SRH after URSL was 0.39%. The incidences of SRH after rigid URSL and flexible URSL were 0.38% and 0.41%, respectively. Unendurable ipsilateral flank pain and a significant decrease in haemoglobin after surgery were the typical clinical manifestations of SRH after URSL. There were no significant differences in age, sex, history of diabetes mellitus, preoperative hypertension, body mass index, stone laterality or perfusion pressure (p>0.05). However, SRH was significantly associated with the stone size, stone location, degree of hydronephrosis and operative duration (p<0.01). One patient was managed conservatively without further intervention, percutaneous drainage was performed in four patients and one patient underwent emergency angiography. No patients died of SRH. CONCLUSIONS: SRH is a rare but potentially serious complication of URSL. Severe hydronephrosis and a thin renal cortex preoperatively and prolonged operative duration are strong predisposing factors for SRH. Laparoscopic ureterolithotomy should be considered as an alternative surgery for patients with severe ureteral tortuosity. SRH is treated based on patients' clinical manifestations. Most patients can be managed with conservative treatment or percutaneous drainage alone.

Ureterorenoscopic (URS) Lithotripsy and Balloon Dilation Cause Acute Kidney Injury and Distal Renal Tubule Damage: A Prospective Study.

Ureterorenoscopy (URS) is believed to be a safe and effective procedure for treating ureteral stones or ureteral strictures. Rapidly increasing intrarenal pressure during URS may have a negative impact on the kidney, but its effect on renal function is not well known. The aim of this study was to evaluate whether URS balloon dilation or lithotripsy could cause acute kidney injury (AKI), which was evaluated using urine neutrophil gelatinase-associated lipocalin (NGAL), and renal tubular damage, which was evaluated using urine α-glutathione S-transferase (GST) and πGST. This prospective study included 207 patients with a mean age of 53.8 years between September 2012 and June 2013. Four groups were included: the ureteral stricture group (group 1), the ureteral stone group (group 2), and two control groups. URS increased urine NGAL (uNGAL) levels on days 1 and 14 in both groups, and only elevated uGST levels were noted on day 14 after URS lithotripsy (URS). On day 14, the difference between low-grade and high-grade hydronephrosis was significant in group 1 (p < 0.001) compared to that in group 2 (p = 0.150). Multivariate logistic regression analysis revealed that age, baseline estimated glomerular filtration rate (eGFR), and stone size > 1.0 cm were associated with the complete recovery of hydronephrosis after URS on day 14. Patients with ureteral stones with preserved renal function had more AKI than those with impaired renal function. However, there was no significant difference in URS-related AKI between the ≤1 cm and >1 cm subgroups. In addition, urine αGST and πGST levels were both significantly higher in the stone > 1 cm subgroup than in the ≤1 cm subgroup. In conclusion, URS laser lithotripsy and balloon dilatation resulted in AKI and renal tubular damage on day 14, although post-URS double-J (DBJ) stenting was performed in every patient.

Symptomatic Hydronephrosis and Ureteral Calculi in Pregnancy: A Narrative Review with a Proposed Management Protocol.

Introduction: Approximately 3% of pregnancies are complicated by symptomatic hydronephrosis and up to 0.8% with urolithiasis. Pain, coupled with the possibility of superimposed infection, increases the risks of premature labor and delivery, fetal loss, and caesarian sections. Surgical intervention as well as standard ionizing radiation imaging modalities are typically avoided making this a difficult, high-risk patient cohort to manage. In this study we propose a standardized contemporaneous approach to investigations and management in the pregnant population with acute upper tract pathology analysis. Methods: A literature search of PubMed, Cochrane, and EMBASE databases was performed to identify original, peer-reviewed articles from 2010 onward on the management of ureteral calculi and symptomatic hydronephrosis occurring during pregnancy. Search yielded 5636 articles and after exclusions, 24 full-text articles met inclusion criteria for analysis. Evidence Synthesis: Ultrasound remains the cornerstone of initial investigation with MRI in reserve if the diagnosis remains uncertain. Low-dose CT imaging can be used in limited cases. Conservative approaches for symptomatic hydronephrosis as well ureteral calculi is the preferred initial management option in the well patient. If intervention is required, ureteral stent and nephrostomy can be used with informed consent on the risks and benefits of each. Primary ureteroscopy with definitive stone management in centers with the appropriate expertise can safely deliver excellent stone-free rates and symptomatic improvement. Conclusions: Individualized investigation and management plans following a structured approach in pregnant women with symptomatic hydronephrosis or calculi are discussed. At all stages, the patient, obstetrician, anesthetist, and surgeon should be involved in a shared decision-making approach.

The use of biomarkers in the diagnosis and treatment of obstruction of the upper urinary tract in children.

Antenatal hydronephrosis, dilatation of the upper urinary tract (UUTD), is a common finding on prenatal ultrasound. One of the most common causes is ureteropelvic junction (UPJ) obstruction. Although such prenatally diagnosed UUTD resolves spontaneously in most newborns, further examination of these children is advocated to prevent possible irreversible kidney damage, and ultrasound is mainly used for this. If the dilatation persists or becomes symptomatic, it is necessary to proceed to other relatively demanding and invasive diagnostic examinations for these small patients, where the question of the right timing of indications for possible surgical solutions is still unclear. For this reason, various biomarkers have been investigated in a number of clinical trials as potential mini-invasive diagnostic tools for determining when upper urinary tract dilatation in such children poses a threat to the developing kidneys and they should be operated on, and vice versa, when to proceed conservatively. The aim of this article is to review the findings on and current issues with the use of biomarkers in the diagnosis and treatment of UPJ obstruction in children.

Non-surgical management of vesicoureteral junction obstruction: a case report.

OBJECTIVE: To report the case of a pediatric patient with bilateral hydronephrosis due to vesicoureteral junction obstruction (VUJO) that was treated non-surgically and to discuss the approach of this anomaly. CASE DESCRIPTION: A 25-month-old boy was referred without complaints for consultation due to prenatal ultrasound showing kidneys with cysts. He was under antibiotic prophylaxis. No family history of kidney disease and/or inherited disorders was reported. Renal ultrasound (RUS) at 2 days of life showed bilateral hydronephrosis, thus ruling out the possibility of kidney cystic disease. Dynamic renal scintigraphy (DTPA) showed marked retention of the marker in the pyelocaliceal system bilaterally, with little response to diuretic drug. He was maintained under antibiotic prophylaxis, when a new RUS showed bilateral ureteral dilatation, abrupt stenosis in the ureterovesical transition region (0.2 cm caliber), moderate bilateral hydronephrosis, and slight renal cortical thickness, confirming the diagnosis of VUJO. At 2 years and 10 months of age, DTPA showed hydronephrosis and ureteral stasis in both kidneys secondary to stenosis at the vesicoureteral junction (VUJ) level, with preservation of kidney function and slow degree of emptying. We opted for a non-surgical approach. RUS at 10 years of age showed significant improvement of all parameters, with ureteral transverse diameter of 9 mm, preserved VUJ, and age-appropriate bilateral kidney development. COMMENTS: VUJO is a major cause of prenatal hydronephrosis and can trigger a deterioration of kidney function. Its treatment is still controversial but should take into account the importance of clinical follow-up and serial imaging evaluation.

[A Case of Descending Colon Cancer with Long-Term Maintenance of QOL by Multidisciplinary Treatment Approach for Locally Recurrent Lesion with Hydronephrosis].

We report a case of recurrent descending colon cancer in which QOL was maintained for a long period by performing resection with intestinal reconstruction, chemotherapy, and radiotherapy for local recurrence with hydronephrosis. A man in his 60s with good ADL underwent laparoscopic left hemicolectomy for descending colon cancer. After 4.5 years postoperatively, computed tomography and positron emission tomography showed a local recurrence of 32 mm contacting with the left external iliac artery and sigmoid colon, and CAPOX plus BEV was started. When cholecystitis developed after 5 chemotherapy courses, the recurrent lesion was resected simultaneously. After 8 months, repeated recurrent lesion with a major axis of 13 mm with left hydronephrosis was observed at the same site. After 3 years of chemotherapy after placing the left ureteral stent, CEA level gradually increased, and tumor growth was observed. Because of the aggressive chemotherapy limitation due to high proteinuria, 66 Gy/22 Fr radiotherapy was performed. After 1 month of radiotherapy, the CEA level decreased and proteinuria improved in that period. Radiotherapy for local recurrence can be a useful interval for chemotherapy and effective local control.

Longitudinal Outcomes from Conservative Management of Cervical Cancer Associated Ureteral Obstruction.

OBJECTIVE: To identify predictors of hydronephrosis (HN) resolution and HN treatment failure. HN is a common comorbid condition with cervical cancer (CCa). Treatments for CCa continue to improve and long-term management strategies of HN are becoming increasingly necessary. METHODS: A query of a single hospital (2004 - 2019) ICD-9 and CPT codes was made to develop a cohort of CCa patients with HN. A retrospective review was performed. The effects of patient, renal/HN, and cancer covariates on time to HN treatment failure, treatment complications and time to HN resolution were evaluated using logistic regression and competing risk Cox regression models. RESULTS: Of the 1670 women treated for CCa during the study period, 179 (10.7%) developed HN (n = 72 (40%) bilateral), 78 (44%) at time of CCa diagnosis and 101 (56%) as a result of treatment, of which 145 (81%) underwent initial treatment with a PCN (n = 77, 53%) or US (n = 68, 47%). Complication rates were similar between PCN (56%) and US (61%) when adjusting for treatment time. Initial treatment failure was more likely with US vs PCN (HR 3.2, P <0.01). HN resolution (n = 32, 22%) without reconstruction was predicted by HN concurrent with CCa diagnosis (HR 3.1, P <0.01) and bilateral HN (HR 0.2, P <0.01). CONCLUSION: CCa associated HN has a resolution rate of only 19% at 12 months. Those presenting with HN after CCa treatment are less likely to resolve without reconstruction. PCN and US have similar complication rates but initial US placement has a nearly three times increased risk of failing than PCN.

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.

Maternal hydronephrosis in pregnant women without ureteral stones and characteristics of symptomatic cases who need treatment: A single-center prospective study with 1026 pregnant women.

PURPOSE: The aim of this study is to determine the proportion of maternal hydronephrosis and symptomatic cases requiring treatment in pregnant women without ureteral stones and the characteristics of these cases. MATERIALS AND METHODS: Between February 2018 and April 2019, all pregnant women followed for pregnancy in obstetrics and outpatient policlinic were evaluated prospectively. Maternal hydronephrosis rate, degree of hydronephrosis and side, symptomatic hydronephrosis rate, maximum renal anteroposterior diameter of renal pelvis and visual analogue scale were detected. Symptomatic patients were treated conservatively or surgically. Findings in both treatment groups were analyzed by t-test or Chi-squared test. Pearson or Spermean's tests were used for correlation analyzes. RESULTS: A total of 1026 pregnant women aged 18-45 (27.7 ± 5.2 years) were followed prospectively. The rate of maternal hydronephrosis was 28.7% and the rate of symptomatic hydronephrosis was 4.7%. Of the patients with symptomatic hydronephrosis, 73.4% (3.5% of total) were treated conservatively and 26.5% (1.3% of total) were treated surgically. There was a positive correlation between hydronephrosis and gestational week (p < 0.001), visual analogue scale (p < 0.001) and hematuria (p < 0.05). There was a negative correlation between hydronephrosis and maternal age (p < 0.05) and number of pregnancies (p < 0,001). The anteroposterior diameter of renal pelvis (p < 0.001), visual analogue scale (p < 0.05) and fetal body weight values (p < 0.05) on the right side were higher in the surgical treatment group than the conservative group. CONCLUSIONS: The majority of cases with maternal hydronephrosis in pregnant women without ureteral stones are asymptomatic. Most symptomatic cases can also be treated conservatively. In cases requiring surgical treatment (1.3%), fetal body weight, visual analogue scale and anteroposterior renal pelvis diameter are higher.

Evaluation and fetal intervention in severe fetal hydronephrosis.

PURPOSE OF REVIEW: Fetal hydronephrosis secondary to congenital anomalies of the kidney and urinary tract (CAKUT) can adversely affect neonates in the postnatal period with long-term consequences. A prenatal diagnosis of CAKUT can have an early fetal intervention to minimize these consequences. This review aims to provide an overview of the possible fetal intervention with severe hydronephrosis. RECENT FINDINGS: Clinical course and outcomes of CAKUT are predicted based on biochemical markers and radiological findings. In spite of advancements and accurately diagnosing the severity of hydronephrosis, there are many controversies surround on selection of cases with antenatal hydronephrosis (ANH) that will benefit from fetal intervention. Despite better diagnosis and techniques fetal intervention is limited to mainly lower urinary tract obstruction patients to improve amniotic fluid volume and assist in lung development. SUMMARY: ANH can potentially detect the severity of congenital renal anomalies but unable to recognize a specific disease. A multidisciplinary approach is required to diagnose and properly stage cases of severe CAKUT and potential surgical intervention can be considered.

Diagnosis and Management of Kock Afferent Nipple Valve Obstruction.

OBJECTIVE: To characterize afferent nipple valve obstruction in Kock diversions presenting with hydronephrosis and discuss appropriate work-up and management. METHODS: We retrospectively reviewed 7 cases of afferent nipple valve obstruction. RESULTS: The median time from diversion creation to afferent nipple valve intervention was 17-years. Presentations included febrile-UTIs, worsening renal function and hydronephrosis. All patients underwent upper tract imaging confirming bilateral hydronephrosis or hydronephrosis of a solitary kidney followed by nephrostomy tube insertion to drain the obstructed kidney(s). On nephrostogram assessment afferent nipple valve obstruction was confirmed by a lack of contrast passing through the valve. In 4 of these patients the afferent valve could not be cannulated while in one patient endoscopic retrograde balloon dilation was performed but failed after 12-months. One patient had successful antegrade balloon dilation (four-years follow-up). In five patients and the one patient who failed retrograde balloon dilation open surgical repair of the afferent nipple valve was successful (median follow-up time 5-years). CONCLUSION: It is essential to consider afferent nipple valve obstruction in a patient with a Kock diversion presenting with bilateral hydronephrosis/hydronephrosis of a solitary kidney, even after many years following the original diversion. Appropriate work-up consists of upper tract imaging, endoscopy and retrograde studies or nephrostomy insertion with nephrostogram. Management options include endoscopic retrograde or antegrade balloon dilation or valve incision. Failing that, surgical repair may be successful with long-term upper tract preservation.

Including Medical Management in the Urologic Approach to Idiopathic Retroperitoneal Fibrosis.

OBJECTIVE: To characterize the timing and effectiveness of medical management in resolving stent-dependent ureteral compression secondary to idiopathic retroperitoneal fibrosis (RPF), the long-term relevant outcomes, and the side effects of treatment. METHODS: A retrospective review of RPF patients diagnosed from 2002-2018 was performed. Patients with hydronephrosis due to ureteral involvement that were managed with medication and with temporary stenting as needed, but without initial ureterolysis, were included. Patient demographics and RPF management details were obtained, including the following subsequent events: ureterolysis, nephrectomy, recurrent upper tract obstruction, and medication side effects. RESULTS: Fifty-two patients met inclusion criteria. Resolution of ureteral obstruction with medical management and temporary renal drainage as needed occurred in 36 (69%) patients with a median stent duration of 16 months, and median clinical and radiographic follow up of 4.2 and 3.3 years, respectively. Recurrent obstruction after a stent-free period occurred in 9 (18%) patients. Ureterolysis was performed in 8 (15%) patients at a median of 2.2 years for medication intolerance, lack of radiographic response to medication, or persisting pain. Potential medication side effects occurred in 6 (12%) patients. CONCLUSIONS: Medical management supported successful resolution of ureteral obstruction in 69% of patients without the need for ureterolysis after temporary renal drainage using stents, with rare incidence of worsening renal dysfunction or medication side effect. To date, this is the largest reported series of systematically managed RPF patients with obstructive uropathy receiving initial medical therapy and serves to counsel patients and advise urologists and nephrologists of the expected course and advantages and disadvantages of medical versus surgical management.

Ureteropelvic junction obstruction: diagnosis and management.

PURPOSE OF REVIEW: Ureteropelvic junction obstruction (UPJO) is the most common cause of prenatally diagnosed hydronephrosis. Although associated with obstruction of the kidney, the natural history is variable, ranging from spontaneous resolution to progressive loss of function over the first few years of life. As a result, the optimal evaluation strategy and indications for treatment have not been well defined. The purpose of this article is to review recent literature focused on the prenatal and postnatal evaluation of infants with prenatally diagnosed hydronephrosis suspicious for UPJO. RECENT FINDINGS: Recent studies have focused on the effect of the urinary tract dilation (UTD) ultrasound classification system, as well as use of magnetic resonance imaging both prenatally and postnatally to stratify the risk of infants with prenatally diagnosed hydronephrosis to develop renal impairment or undergo surgery. Additionally, urinary biomarkers have been identified as a potential noninvasive alternative to diuretic renography in identifying infants with clinically significant UPJO. SUMMARY: Although continued work is needed to develop clear guidelines for evaluation and treatment and to better define long-term outcomes, these studies offer novel approaches to improve the care of these patients.

Hydronephrosis: Diagnosis, Grading, and Treatment.

Hydronephrosis, or dilation of the renal collecting system, can be diagnosed using various modalities, including sonography, radiography, magnetic resonance imaging, and nuclear medicine technology. This article explores the causes of hydronephrosis and its effects on the urinary system, presenting signs, symptoms, diagnostic techniques, and the role of various imaging specialists. In addition, the grading scale for hydronephrosis is presented and treatment options are explained.