Systematic Review of Urologic Outcomes from Tethered Cord Release in Occult Spinal Dysraphism in Children.

Tethered cord syndrome describes a condition of multisystem end organ dysfunction due to fixation of the spinal cord. This systematic review focuses on the closed skin variant of this condition, occult spinal dysraphism. The embryology, pathophysiology, presentation, and classification of occult spinal dysraphism are explained to develop a simple framework for discussions regarding this often confusing condition. Following Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, we synthesized urologic outcome data after tethered cord release in children from 17 studies performed over the past 25 years. These results prompted several conclusions. First, the different subgroups and different nomenclature of tethered cord syndrome are often confused, making interpretation of results difficult. Second, untethering has a positive effect on urologic symptoms and urodynamics parameters. Third, timing of untethering is important: early intervention prevents significant long-term traction aiming to avoid irreversible neurologic damage. Fourth, pediatric urologists and neurosurgeons have an important role in diagnosing and treating this condition and should work closely as part of a multidisciplinary team.

Notch signaling, wt1 and foxc2 are key regulators of the podocyte gene regulatory network in Xenopus.

Podocytes are highly specialized cells in the vertebrate kidney. They participate in the formation of the size-exclusion barrier of the glomerulus/glomus and recruit mesangial and endothelial cells to form a mature glomerulus. At least six transcription factors (wt1, foxc2, hey1, tcf21, lmx1b and mafb) are known to be involved in podocyte specification, but how they interact to drive the differentiation program is unknown. The Xenopus pronephros was used as a paradigm to address this question. All six podocyte transcription factors were systematically eliminated by antisense morpholino oligomers. Changes in the expression of the podocyte transcription factors and of four selected markers of terminal differentiation (nphs1, kirrel, ptpru and nphs2) were analyzed by in situ hybridization. The data were assembled into a transcriptional regulatory network for podocyte development. Although eliminating the six transcription factors individually interfered with aspects of podocyte development, no single gene regulated the entire differentiation program. Only the combined knockdown of wt1 and foxc2 resulted in a loss of all podocyte marker gene expression. Gain-of-function studies showed that wt1 and foxc2 were sufficient to increase podocyte gene expression within the glomus proper. However, the combination of wt1, foxc2 and Notch signaling was required for ectopic expression in ventral marginal zone explants. Together, this approach demonstrates how complex interactions are required for the correct spatiotemporal execution of the podocyte gene expression program.

Surge in testicular torsion in pediatric patients during the COVID-19 pandemic.

BACKGROUND: Testicular torsion is a pediatric surgical emergency, and prompt diagnosis and treatment is imperative. During the COVID-19 pandemic, pediatric patients with symptoms of testicular torsion may be reluctant to seek medical care which increases the likelihood of delayed presentation and the need for an orchiectomy. This observational study sought to determine whether there was a higher number of testicular torsion cases during COVID-19. METHODS: As the first patient with COVID-19 was admitted to our facility on March 6, 2020, we identified male children ages 1-18 years with testicular torsion between March 1-December 31, 2020 (during COVID-19) compared to the same time period between 2015 and 2019 (prior to COVID-19). All patients were evaluated at our Institution's Emergency Department by a pediatric urologist. RESULTS: There were 38 cases of testicular torsion between March 1-December 31, 2020 compared to 15.8 cases on average during the same 10-month period between 2015 and 2019 (a total of 79 cases). There was a statistically significant increase in testicular torsion cases during the COVID-19 pandemic compared to equivalent time periods in 2015-2019 (38 vs. 15.8, p = 0.05). Patients with testicular torsion during the COVID-19 pandemic were younger, had a longer duration of symptoms, and had a higher number of orchiectomies (although not statistically significant). CONCLUSION: During the COVID-19 pandemic, an escalation in testicular torsion cases was observed. Timely assessment, diagnosis, and surgery are crucial to prevent testicular loss and potential infertility in the future. Further evaluation is needed to elucidate the surge in testicular torsion and possible mechanisms.

Case Report: Novel Copy Number Variant 16p11.2 Duplication Associated With Prune Belly Syndrome.

Prune belly syndrome (PBS) is a rare congenital disease that predominantly occurs in males and is identified by its classic triad of abdominal wall musculature deficiencies, cryptorchidism, and urinary tract abnormalities. However, numerous anomalies involving the kidneys, heart, lungs, and muscles have also been reported. A multitude of chromosomal abnormalities have been implicated in its pathogenesis. PBS can occur in association with trisomy 18 and 21. Gene duplications and deletions have also been reported; however, a definite cause of PBS is still unknown. We report the first PBS patient with a copy number variant in 16p11.2.

Case Report: Rare Presentation of Mixed Germ Cell Tumor in an Infant.

The estimated incidence of pediatric testis tumor is 0.5-2.0 per 100,000 children, accounting for 1-2% of all pediatric tumors. Mixed germ cell tumors (MGCT) in prepubertal males are exceedingly rare, with only one previous case report found in the literature. We report a case of a MGCT in an infant. For prepubertal males, GCTs typically present with a painless scrotal mass, though trauma, testis torsion and hydrocele are also common presentations. Similar to such tumors in postpubertal males, ultrasonography, computed tomography, and tumor markers are integral to determine the best treatment. The patient described in this report presented with a painless scrotal mass. Following orchiectomy, the patient was found to have MGCT that was limited to the testis. With prudent management, these patients tend to have favorable prognoses.

Case Report: Penile Strangulation Secondary to Hair Tourniquet.

Penile strangulation is a rare condition in children caused by circumferential constriction of the coronal sulcus by constricting material, commonly thin maternal hair. Vague presenting symptoms often makes diagnosis difficult, but delay in diagnosis can lead to a variety of severe complications including urethral injury and penile necrosis. Providers must have a high index of suspicion and carry out a careful examination to identify maternal hair strands that may bury deep within penile edema. We describe two cases of penile strangulation secondary to maternal hair strands that were successfully treated with thorough examination and division of the constricting hair in the emergency department. In both cases, presentation involved penile swelling and erythema which was noticed by caregivers. Once the diagnosis has been made, urgent treatment using depilatory cream or mechanical removal must occur, with urgent referral to specialists if unable to remove to constricting material. Caregivers must also be counseled on appropriate steps to prevent penile hair tourniquet syndrome. Devastating complications can be avoided by early recognition and proper management of the syndrome, but providers must have knowledge of the condition and a high index of suspicion.

Challenges in the Prenatal Diagnosis of Cloaca.

BACKGROUND: Cloaca is a common excretory channel for the genital, urinary, and gastrointestinal tracts. It is considered a severe anorectal malformation caused by failed partitioning of the genital, rectal, and urinary tracts. METHODS: We report 5 infants with cloaca at birth who were identified prenatally by one or more of the following on prenatal ultrasound (US): ambiguous genitalia, a cystic pelvic/abdominal mass, hydronephrosis, ascites, a single umbilical artery, and oligohydramnios. RESULTS: A cystic pelvic/abdominal mass and ambiguous genitalia were each observed in 3 cases by prenatal US. Ambiguous genitalia was observed in all 5 neonates at birth. There were 2 twin pregnancies (dichorionic/diamniotic and monochorionic/monoamniotic), with only 1 twin in a set affected with cloaca. CONCLUSION: Pediatricians should be alert to the prenatal US findings that may raise suspicion of a persistent cloaca to improve both prenatal counseling and family preparation.

Anterior urethral valves - A rare but challenging congenital pathology.

BACKGROUND: Anterior urethral valves (AUV) and associated anterior urethral diverticula (AUD) are a rare cause of congenital lower urinary tract obstruction. They occur 25-30 times less frequently than posterior urethral valves (PUV) and historically tend to have a less aggressive presentation and outcome. However, due to the low incidence, little is known about management and long-term prognosis. OBJECTIVE: We aim to evaluate the outcomes after AUV valve ablation and compare this group to a previously studied PUV cohort. STUDY DESIGN: In this IRB-approved study, we retrospectively identified all patients from 2002 to 2017 undergoing valve ablation using CPT code 52400. Charts were manually reviewed to identify AUV patients, their presenting symptoms, timing of diagnosis, pre and postnatal imaging findings, age at presentation and valve ablation, creatinine, recurrences, additional surgeries and follow-up. The AUV group was then compared to a previously studied PUV cohort of 104 patients from our institution. RESULTS: Nine AUV patients were identified. Only four (44%) patients were diagnosed prenatally. Three (33%) patients were diagnosed neonatally, one for weak stream/dribbling and two for febrile UTIs. The remaining two patients were diagnosed at ages 3 and 4 due to dysuria and penile swelling with micturition. Patients presenting later in life had no evidence of renal dysfunction or VUR. All patients underwent primary TUR-AUV (1 laser, 4 cold knife, 4 cautery), but 55% had residual valves and/or diverticula identified on routine postoperative imaging in two patients and due to development of clinic symptoms in three patients. All five patients with recurrences underwent repeat endoscopic evaluation, and thereafter two patients required urethral reconstruction. In contrast, only 15% (16/104) of PUV patients required re-TUR (p = 0.01). At an average follow-up time of 4.24 years (range 0.6-11.4 years), 44% of patients had no evidence of CKD, and two patients (22%) had progressed to CKD of at least stage IIIA, compared to 21.4% in the PUV cohort at a mean follow-up of 2.3 years. DISCUSSION: The overall incidence of AUV is low, making it difficult to characterize these patients definitively. However, despite a milder phenotype and later presentation in most AUV patients, they do require more aggressive surgical treatment for complete resolution of the AUV. Furthermore, the long-term renal outcomes appear more severe than previously reported. CONCLUSIONS: The poorer outcomes of AUV patients both with respect to recurrence and long-term CKD indicate that close urologic follow-up is essential in this group.

Delayed Presentation of Urethral Valves: A Diagnosis That Should Be Suspected Despite a Normal Prenatal Ultrasound.

Background. Congenital urethral obstruction occurs most frequently as a result of urethral valves. The diagnosis is usually confirmed pre- or neonatally. Though not ideal, delayed diagnosis can occur in childhood, adolescence, or adulthood. Despite a normal prenatal ultrasound, there may still be a delayed diagnosis of urethral valves. Methods. We present 4 patients with delayed diagnosis of posterior urethral valves (PUV) and 1 patient with delayed diagnosis of anterior urethral valves (AUV) who were evaluated by a pediatric urologist at our Institution. We determined the age and symptoms at presentation, physical examination, micturating cystourethrogram (MCU) findings prior to the valve ablation, renal function before and after valve ablation, type of valve ablation, and urine culture and sensitivity. The urological courses following urethral valve ablation including urodynamic study findings are described. Results. The median age at presentation was 33 months. All 5 patients presented with decreased urine output and urinary retention. All 5 patients underwent a MCU that demonstrated bladder trabeculations (3 cases), vesicoureteral reflux (3 cases), and bladder diverticula (2 cases). A urethral valve ablation was performed in all cases. Four patients underwent a renal function panel prior to this procedure, and their serum BUN/creatinine levels decreased 1 day postoperatively. Conclusion. Pediatricians should consider urethral valves as causing urethral obstruction although the prenatal ultrasound may be normal. Early diagnosis and prompt treatment of urethral valves may mitigate the potentially devastating morbidities such as renal failure, congestive heart failure, and respiratory distress that may ensue.

Quantifying the forces needed for ureteral stent removal: Initial evaluation of magnetic stent removal devices on benchtop and porcine models.

BACKGROUND: Indwelling ureteral stents are commonly used in pediatric surgeries for kidney stones and urinary tract obstruction, but often require instrumentation or anesthesia for removal. We evaluated the use of novel magnet devices to remove indwelling ureteral stents with a distally attached magnetic bead. Since the forces required for stent removal are unknown, we aimed to characterize and quantify the forces required for stent removal for future prototype testing. METHODS: A custom 3-D urinary tract model was used for benchtop testing, and 6 female porcine subjects were used for in vivo testing after obtaining institutional approval. A modified porcine urethral model that patterned the human female urethral anatomy with approximately 4.5 cm urethral length was used. A HF-10 digital force gauge measured the force required to remove stents with varying properties (stent size, presence of curl, and size of distal magnetic bead). These force measurements were compared to the quantified magnetic forces generated by external magnets and catheter tip magnets. Furthermore, the magnetic retrieval devices were tested with various magnetic beads on both benchtop and porcine models. RESULTS: The required force for removal of a 5 Fr x 14 cm double J stent was significantly higher in the benchtop model compared to the porcine model (4.7N v. 0.8N, p < 0.001). Forces of at least 1N were required from the external magnets to move the stent and bead across a 4-5 cm distance from the bladder neck to the urethral meatus. External magnets at a distance of 4-5 cm produced insufficient forces for removal, and thus they failed to remove the magnetic bead and stent from the bladder. The catheter-based retrieval device showed better success with a variety of different magnet pairs on the retrieval device and stent. Furthermore, the addition of saline to the bladder allowed for better retrieval rates of the smallest beads, even by the smallest magnetic tip catheters. CONCLUSIONS: The forces required for ureteral stent removal are <1N in the porcine model, and improved benchtop models that emulate such parameters will facilitate future stent removal device testing. Given this threshold, external magnets did not generate sufficient force for stent removal at the required distance of 4-5 cm, whereas catheter tip magnetic retrieval overcomes the minimum distance limitation and showed successful retrieval. While these results are encouraging, further studies will define the optimal combination of catheter magnetic tip size and stent magnetic bead size.

Scrotal Ultrasound Is Not Routinely Indicated in the Management of Cryptorchidism, Retractile Testes, and Hydrocele in Children.

Cryptorchidism, or undescended testes, is the most common congenital genitourinary anomaly. A failure or delay of treatment may result in reduced fertility or an increased risk of testicular cancer. The American Urological Association (AUA) recommends that a scrotal ultrasound (SUS) not be performed in the preoperative management of cryptorchidism. This study investigated how likely pediatricians were to perform SUS despite the AUA guidelines. We retrospectively studied 243 patients referred to a single pediatric urology practice for clinically diagnosed testis pathology including undescended testis, hydrocele, and retractile testis over a 4-year period (January 1, 2015, to December 30, 2018). A total of 72 patients (29.6%) underwent a SUS ordered by their pediatrician prior to the pediatric urology visit. Pediatricians should be aware that SUS performed prior to pediatric urological evaluation does not alter management and is associated with a significant financial cost in patients with cryptorchidism or hydrocele.

Hypospadias Risk from Maternal Residential Exposure to Heavy Metal Hazardous Air Pollutants.

Objective: Investigate whether residential prenatal exposure to heavy metal hazardous air pollutants (HMHAPs) is associated with an increased risk of hypospadias. Methods: Data on non-syndromic hypospadias cases (n = 8981) and control patients delivered in Texas were obtained from the Texas Birth Defects Registry and matched 1:10 by birth year. Average exposure concentrations of HMHAPs were obtained from the 2005 U.S. Environmental Protection Agency National-Scale Air Toxics Assessment and categorized into quintiles. Odds ratios and 95% confidence intervals were estimated. STROBE reporting guidelines were followed. Results: We observed associations between hypospadias and prenatal HMHAP exposure. Manganese demonstrated significant increased risk of hypospadias at the medium, medium-high and high exposure quintiles; lead in the medium-high and high exposure quintiles. Cadmium, mercury and nickel demonstrated a significant inverted "U-shaped" association for exposures with significant associations in the medium and medium-high quintiles but not in the medium-low and high quintiles. Arsenic and chromium demonstrated a significant bivalent association for risk of hypospadias in a lower quintile as well as a higher quintile with non-significant intermediate quintiles. Conclusions: Using data from one of the world's largest active surveillance birth defects registries, we identified significant associations between hypospadias and HMHAP exposures. These results should be used in counseling for maternal demographic risk factors as well as avoidance of heavy metals and their sources.

Hypospadias risk is increased with maternal residential exposure to hormonally active hazardous air pollutants.

BACKGROUND: With the increasing birth prevalence of hypospadias, there is growing concern for pollutant exposure interfering with normal penile development. We assess the association between hypospadias and hormonally active hazardous air pollutants (HAHAPs) through a nationwide database of hazardous air pollutants and the Texas Birth Defects Registry (TBDR). METHODS: Using the TBDR, we identified 8,981 nonsyndromic isolated hypospadias cases from 1999 to 2008. Birth certificate controls were matched for birth year at a 10:1 ratio to cases. Estimated HAHAP concentrations from the 2005 U.S. EPA National-Scale Air Toxics Assessment were used to assign exposure based on maternal residence at birth. Exposure levels were categorized as quintiles based on the distribution in controls. Logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (CI) for each increasing exposure category of selected HAHAPs. RESULTS: Of the 10 HAHAPs studied, seven were significantly associated with hypospadias risk. The HAHAP that was most strongly associated with hypospadias was phenol, which was associated with risk in all groups except the high exposure group. Cumulative HAHAP exposure demonstrated a modest increase in hypospadias risk (OR 1.15, 95% CI: 1.07-1.24, p < 0.001) in the medium and medium-high quintiles. CONCLUSIONS: While maternal exposure to some HAHAPs was significantly associated with the risk of hypospadias in male offspring, the effects were modest, and no dose-response effects were observed. Future work should employ biomarkers of exposure to better delineate the relationship.

Surgical interventions and anesthesia in the 1st year of life for lower urinary tract obstruction.

BACKGROUND: Patients with a prenatal diagnosis of lower urinary tract obstruction (LUTO) may undergo prenatal interventions, such as vesicoamniotic shunt (VAS) placement, as a temporary solution for relieving urinary tract obstruction. A recent FDA communication has raised awareness of the potential neurocognitive adverse effects of anesthesia in children. We hypothesized as to whether a prenatal LUTO staging system was predictive of the number of anesthesia events for prenatally diagnosed LUTO patients. METHODS: We retrospectively reviewed the prenatal and postnatal clinical records for patients with prenatally diagnosed LUTO from 2012 to 2015. Patients were stratified by prenatal VAS status and by LUTO disease severity according to Ruano et al. (Ultrasound Obstet Gynecol. 2016). RESULTS: 31 patients were identified with a prenatal LUTO diagnosis, and postnatal records were available for 21 patients (seven patients in each stage). When combining prenatal and postnatal anesthesia, there was a significant difference in the number of anesthesia encounters by stage (1.6, 3.7, and 6.7 for Stage I, II, and III respectively, p = .034). Upon univariate analysis, higher gestational age (GA) at birth was associated with a decreased number of anesthesia events in the first year (p = .031). CONCLUSIONS: The majority of infants with prenatally diagnosed LUTO will undergo postnatal procedures with general anesthesia exposure in the first year of life. Patients with higher prenatal LUTO severity experienced a higher number of both prenatal and postnatal anesthesia encounters. In addition, higher GA at birth was associated with fewer anesthesia encounters in the first year. LEVEL OF EVIDENCE: This is a prognostic study with Level IV evidence.

Evaluating Outcomes of Differential Surgical Management of Nonfunctioning Upper Pole Renal Moieties in Duplex Collecting Systems.

OBJECTIVE: To evaluate the management and clinical outcomes of nonfunctioning upper pole moieties treated with either upper pole heminephrectomy or upper pole preservation with lower ureteral reconstruction at a single tertiary institution. METHODS: After Institutional Review Board (IRB) approval, patients with duplicated systems undergoing upper pole heminephrectomy, ureteroureterostomy, or common sheath ureteral reimplantation from 2012-2017 were identified. Only patients with a nonfunctioning upper pole moiety on ultrasound or renal scan were included. Patients undergoing upper pole heminephrectomy were compared to those undergoing upper pole preservation with respect to demographics, anatomic variations preoperatively, and postoperative outcomes. RESULTS: Twenty-seven (57%) patients underwent upper pole preservation with lower ureteral reconstruction; 20 (43%) patients underwent upper pole heminephrectomy. Patients undergoing lower ureteral reconstruction were older (1.63 vs 2.76 years, P = .018) and more commonly presented with lower pole vesicoureteral reflux (67% vs 25%, P = .008). No significant difference in postoperative complications was seen between the two groups. After ureteroureterostomy, one patient developed new onset symptomatic reflux to the upper pole requiring intravesical reimplantation. In the heminephrectomy group, 4 of 11 patients with ureteroceles had ureterocelectomy with concomitant lower pole reimplantation. After heminephrectomy, two additional patients required further interventions: ureterocele excision and transurethral polyp excision. CONCLUSION: For patients with nonfunctional upper poles, lower tract reconstruction is a safe alternative to upper pole heminephrectomy. No significant difference in outcomes was seen. Considering that nearly 1 of 3 of patients with upper pole heminephrectomy required additional lower urinary tract procedures, pursuing upper pole preservation with lower urinary tract reconstruction may be favorable.

Corrigendum: Vesicoamniotic Shunting Improves Outcomes in a Subset of Prune Belly Syndrome Patients at a Single Tertiary Center.

[This corrects the article DOI: 10.3389/fped.2018.00180.].

Vesicoamniotic Shunting Improves Outcomes in a Subset of Prune Belly Syndrome Patients at a Single Tertiary Center.

Objective: Review outcomes of Prune Belly Syndrome (PBS) with the hypothesis that contemporary management improves mortality. Methods: A retrospective chart review of inpatient and outpatient PBS patients referred between 2000 and 2018 was conducted to assess outcomes at our institution. Data collected included age at diagnosis, concomitant medical conditions, imaging, operative management, length of follow-up, and renal function. Results: Forty-five PBS patients presented during these 18 years. Prenatal diagnoses were made in 17 (39%); 65% of these patients underwent prenatal intervention. The remaining patients were diagnosed in the infant period (20, 44%) or after 1 year of age (8, 18%). Twelve patients died from cardiopulmonary complications in the neonatal period; the neonatal mortality rate was 27%. The mean follow-up among patients surviving the neonatal period was 84 months. Forty-two patients had at least one renal ultrasound (RUS); of the 30 patients with NICU RUSs, 26 (89%) had hydronephrosis and/or ureterectasis. Of the 39 patients who underwent voiding cystourethrogram (VCUG), 28 (62%) demonstrated VUR. Fifty-nine percent had respiratory distress. Nine patients (20%) were oxygen-dependent by completion of follow up. Thirty-eight patients (84%) had other congenital malformations including genitourinary (GU) 67%, gastrointestinal (GI) 52%, and cardiac 48%. Sixteen patients (36%) had chronic kidney disease (CKD) of at least stage 3; three patients (7%) had received renal transplants. Eighty-four percent of patients had at least one surgery (mean 3.4, range 0-6). The most common was orchiopexy (71%). The next most common surgeries were vesicostomy (39%), ureteral reimplants (32%), abdominoplasty (29%), nephrectomy (25%), and appendicovesicostomy (21%). After stratifying patients according to Woodard classification, a trend for 12% improvement in mortality after VAS was noted in the Woodard Classification 1 cohort. Conclusions: PBS patients frequently have multiple congenital anomalies. Pulmonary complications are prevalent in the neonate while CKD (36%) is prevalent during late childhood. The risk of CKD increased significantly with the presence of other congenital anomalies in our cohort. Mortality in childhood is most common in infancy and may be as low as 27%. Contemporary management of PBS, including prenatal interventions, reduced the neonatal mortality rate in a subset of our cohort.

Evaluating Natural History and Follow Up Strategies for Non-obstructive Urolithiasis in Pediatric Population.

Objective: While small non-obstructive stones in the adult population are usually observed with minimal follow-up, the same guidelines for management in the pediatric population have not been well-studied. We evaluate the clinical outcomes of small non-obstructing kidney stones in the pediatric population to better define the natural history of the disease. Methods: In this IRB-approved retrospective study, patients with a diagnosis of kidney stones from January 2011 to March 2017 were identified using ICD9 and ICD10 codes. Patients with ureteral stones, obstruction, or stones >5 mm in size were excluded. Patients with no follow-up after initial imaging were also excluded. Patients with a history of stones or prior stone interventions were included in our population. Frequency of follow-up ultrasounds while on observation were noted and any ER visits, stone passage episodes, infections, and surgical interventions were documented. Results: Over the 6-year study period, 106 patients with non-obstructing kidney stones were identified. The average age at diagnosis was 12.5 years and the average stone size was 3.6 mm. Average follow-up was 17 months. About half of the patients had spontaneous passage of stones (54/106) at an average time of 13 months after diagnosis. Stone location did not correlate with spontaneous passage rates. Only 6/106 (5.7%) patients required stone surgery with ureteroscopy and/or PCNL at an average time of 12 months after initial diagnosis. The indication for surgery in all 6 cases was pain. 17/106 (16%) patients developed febrile UTIs and a total of 43 ER visits for stone-related issues were noted, but no patients required urgent intervention for an infected obstructing stone. Median interval for follow-up was every 6 months with renal ultrasounds, which then was prolonged to annual follow up in most cases. Conclusions: The observation of pediatric patients with small non-obstructing stones is safe with no episodes of acute obstructive pyelonephritis occurring in these patients. The sole indication for intervention in our patient population was pain, which suggests that routine follow-up ultrasounds may not be necessary for the follow-up of pediatric non-obstructive renal stones ≤5 mm in size.

Sonographic Renal Parenchymal Measurements for the Evaluation and Management of Ureteropelvic Junction Obstruction in Children.

PURPOSE: To correlate sonographic renal parenchymal measurements among patients with ureteropelvic junction obstruction (UPJO) labeled society of fetal urology (SFU) hydronephrosis grades 1-4 and to examine whether sonographic renal parenchymal measurements could be used to differentiate conservative vs. surgical management. MATERIALS AND METHODS: Retrospective chart review and sonographic renal parenchymal measurements (renal length, medullary pyramid thickness, and renal parenchymal thickness) were performed in patients with SFU grades 1-4 hydronephrosis secondary to UPJO managed between 2009 and 2014. Exclusion criteria included other concomitant genitourinary pathology or incomplete follow-up. Anterior-posterior renal pelvic diameter (APRPD) and radionuclide renography were also evaluated when available. RESULTS: One hundred four patients with UPJO underwent 244 renal and bladder ultrasound (1,464 sonographic renal parenchymal measurements in 488 kidneys). Medullary pyramid thickness and renal parenchymal thickness progressively decreased from SFU grades 1-4 (p < 0.05). A similar trend was appreciated when comparing SFU grades 1 and 2 vs. 3 and 4, as well as SFU grades 3 vs. 4 (p < 0.05). SFU grade 3 and 4 patients who underwent pyeloplasty had longer renal length in comparison to those who were managed conservatively (p < 0.02). CONCLUSION: This is the first study that evaluates these objective, quantifiable sonographic renal parenchymal measurements in children with unilateral UPJO. These sonographic renal parenchymal measurements correlate closely with worsening of hydronephrosis graded by the SFU and APRPD classification systems. Prospective studies are needed to elucidate the role of sonographic renal parenchymal measurements in the management of children with UPJO.