Pyeloplasty with ureteral stent placement in children: Do prophylactic antibiotics serve a purpose?

OBJECTIVES: Ureteral stents are commonly used during pyeloplasty to ensure drainage and anastomotic healing. Antibiotic prophylaxis is often used due to concerns for urinary tract infection (UTI). Although many surgeons prescribe prophylactic antibiotics following pyeloplasty, practices vary widely due to lack of clear evidence-based guidelines. We hypothesize that the rate of stent UTI does not significantly vary between children who receive antibiotics and those who do not. METHODS: We reviewed the medical records of 741 patients undergoing pyeloplasty between January 2010 and July 2018 across seven institutions. Exclusion criteria were: age older than 22 years, no stent placed, externalized stents used, and incomplete records. Surgical approach, age, antibiotic use, stent duration, Foley duration, and urine culture results were recorded. Patients were categorized into two groups, those younger than four years of age and those four years and older as proxy for likely diaper use. Univariate logistic regression was conducted to identify variables associated with UTI. Multivariable backward stepwise logistic regression was used to identify the best model with Akaike information criterion as model selection criteria. The selected model was used to calculate odds ratios and 95% confidence intervals summarizing the association between prophylactic antibiotics and stent UTI while controlling for age, gender, and intra-operative urine cultures. RESULTS: 672 patients were included; 338 received antibiotic prophylaxis and 334 did not. These groups differed in mean age (3.91 vs. 6.91 years, P < .001), mean stent duration (38.5 vs. 35.32 days, P < .001), and surgical approach (53.25% vs. 32.04% open vs. laparoscopic, P < .001). The incidence of stent UTI was low overall (7.59%) and similar in both groups: 31/338 (9.17%) in the prophylaxis group and 20/334 (5.99%) in the non-prophylaxis group (P = .119). Although female gender, likely diaper use, and positive intra-operative urine culture were each associated with significantly higher odds of stent UTI, prophylactic antibiotic use was not associated with significant reduction in stent UTI in any of these groups. Surgical approach, stent duration, and Foley duration were not associated with stent UTI. CONCLUSION: Incidence of stent UTI is low overall following pyeloplasty. Prophylactic antibiotics are not associated with lower rates of stent UTI following pyeloplasty even after controlling for risk factors of female gender, likely diaper use, and positive intra-operative urine culture. Routine administration of prophylactic antibiotics after pyeloplasty does not appear to be beneficial, and may be best reserved for those with multiple risk factors for UTI.

Salvage Surgery Rates for Pediatric Testicular Torsion: Comparison of the Pre- and Post-Quality Metric Eras.

PURPOSE: Pediatric testicular torsion is a urological emergency that requires timely intervention. In 2015, quality metrics for testicular torsion were implemented in the U.S. News & World Report "Best Children's Hospitals" rankings. Our study examines and compares testicular salvage surgery rates before and after the institution of national quality metrics from a multi-institutional database. MATERIALS AND METHODS: The Pediatric Health Information System® was surveyed for all testicular torsion encounters using ICD (International Classification of Diseases), Ninth and Tenth Revisions coding from 52 hospitals between January 2010 and December 2019. Patients <1 year and ≥18 years of age were excluded. Only hospitals that reported outcomes before and after quality scoring were included. Testicular salvage surgery was defined as patients having undergone orchiopexy without concomitant orchiectomy. Age, race, distance from hospital, household income and insurance status were compared. RESULTS: A total of 890 patients (551 pre-metric and 339 post-metric) from 38 hospitals were included. The testicular salvage surgery rate was 12.5% higher in the post-metric cohort (70.9% versus 58.4%). Hospital compliance to testicular torsion quality metrics increased from 62% in 2015 to 98% in 2019. Mean age, race, distance to hospital, household income, insurance status and use of ultrasound were not statistically different between pre- and post-metric cohorts. CONCLUSIONS: Since the implementation of quality metrics, salvage surgery rates for testicular torsion increased to 70.9%, an improvement of 12.5% when compared to pre-metric outcomes. Patient factors were similar between the 2 groups. Multi-institutional prospective data are needed to validate this database study and evaluate overall testicular salvage rate.

Prospective evaluation of radiation dose with conventional fluoroscopic voiding cystourethrogram in pediatric patients.

INTRODUCTION: Skin entrance doses for voiding cystourethrogram (VCUG) have not been well characterized in the literature. Radiation exposure is measured as either dose area product (DAP) or air kerma, which estimates the effective dose, but does not accurately reflect absorbed dose at skin level. OBJECTIVE: The objective of this study was to measure the skin entrance dose during fluoroscopic VCUG study in pediatric patients using single point dosimeters. STUDY DESIGN: Pediatric patients undergoing fluoroscopic VCUG were prospectively enrolled in our study. Landauer NanoDot™OSLD dosimeters were affixed to the skin overlying the sacrum to measure skin entrance dose. The fluoroscopic unit was set to the following parameters: low dose setting, skin-to-source distance of 54 cm, pulsed fluoroscopy at 3 frames/sec. RESULTS: Forty-four patients with a median age of 13.6 months (IQR 3.7-42.3) were enrolled. Median fluoroscopic time was 54 s (IQR 36-72). The median values absorbed dose by dosimeter and air kerma were 0.32 mGy (IQR 0.13-0.56, range 0.01-2.9) and 0.24 mGy (IQR 0.14-0.37), respectively. There was a positive correlation between the air kerma and absorbed dose (r = 0.69, p < 0.001) and fluoroscopy time and absorbed dose mGy (r = 0.60, p < 0.001). Absorbed dose was independent of age, body mass index and body surface area (p = 0.19, p = 0.57 and p = 0.16, respectively). Median whole body effective dose was 0.04 mSv (IQR 0.02-0.7). DISCUSSION: Overall, the absorbed dose received by the dosimeter remained low at a median of 0.32 mGy (range 0.01-2.91). These values are remarkably low and well within the accepted radiation exposure norms. Our radiologists follow a strict protocol to reduce the overall radiation emitted during a VCUG. These measures include setting the x-ray source at a low dose mode, collimating to the smallest area possible, and using pulsed fluoroscopy at 3 frames/sec. Limitations to this study include a slight variability in technique of VCUG between different technicians and providers, for which we cannot control. CONCLUSION: The radiation dose absorbed at the skin entrance and uniform whole body effective dose is low for a single VCUG when utilizing strict parameters. While newer non-ionizing technologies continue to emerge, our data is encouraging and will serve as a valuable tool when educating parents regarding radiation doses associated with a VCUG.

Prostatic cyst in a pediatric patient with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inheritable form of renal cystic disease and is associated with cysts in other organs. Prostatic cysts are rare though and have not been reported in the paediatric population. Reported is the presence of a prostatic cyst that was incidentally noted on routine sonogram in a 15 year old with ADPKD.

Discrepancies in Self-Reported and Actual Conflicts of Interest for Robotic Pediatric Urological Surgery.

PURPOSE: Transparency of conflicts of interest is essential when assessing publications that address the benefits of robotic surgery over traditional laparoscopic and open operations. We assessed discrepancies between self-reported and actual conflicts of interest as well as whether conflicts of interest are associated with favorable endorsement of robotic surgery. MATERIALS AND METHODS: We searched the Embase® and MEDLINE® databases for articles on robotic surgery within pediatric urology. We included English language articles published since 2013, when data in the Open Payments program (Centers for Medicare and Medicaid Services, Baltimore, Maryland) became available. For all United States based authors Open Payments was used to identify the total amount of financial payment received from Intuitive Surgical®. Chi-square test was used to assess the association between conflicts of interest and favorable endorsement of robotic surgery. RESULTS: A total of 191 articles were initially identified. After exclusion criteria were applied 107 articles remained (267 distinct authors). Of the articles 86 (80.4%) had at least 1 author with a history of payment from Intuitive Surgical, with 79 (91.9%) having at least 1 author who did not declare a conflict of interest despite history of payment. A total of 44 authors (16.5%) had a history of payment from Intuitive Surgical, with an average payment of $3,594.15. Articles with a first and/or last author with a history of payment were more likely to contain a favorable endorsement of robotic surgery compared to articles without a history of payment (85.1% vs 63.6%, p = 0.0124). CONCLUSIONS: Nondisclosure of conflict of interest with Intuitive Surgical is extremely common within pediatric urology. Steps to ensure accurate reporting of conflicts of interest are essential. There appears to be an association between a history of payment and favorable endorsement of robotic surgery.

Urologic Phenotype and Patterns of Care in Patients With Megacystis Microcolon Intestinal Hypoperistalsis Syndrome Presenting to a Major Pediatric Transplantation Center.

OBJECTIVE: To describe the phenotype, referral pattern, and trends of urologic management for children with megacystis microcolon intestinal hypoperistalsis syndrome. MATERIALS AND METHODS: We performed a retrospective review of all patients with megacystis microcolon intestinal hypoperistalsis syndrome treated at a large tertiary children's medical center over a 14-year period. Our primary outcomes included the rate of urology referral, urodynamic characteristics of bladder function, and the proportion of patients managed with clean intermittent catheterization. RESULTS: Twenty-six patients were evaluated at our institution with a median age at presentation of 1.3 years (73% female, 19 of 26). Most patients presented for intestinal transplantation evaluation and were dependent on parenteral nutrition. Megacystis was diagnosed prenatally in 15 patients and postnatally in 11 patients. Twenty patients (77%, 20 of 26) were evaluated by a pediatric urologist. Six patients (23%, 6 of 26) had varying degrees of vesicoureteral reflux. Early bladder management consisted of clean intermittent catheterization in 13 patients and vesicostomy in 8 patients. CONCLUSION: Megacystis microcolon intestinal hypoperistalsis syndrome is a severe form of intestinal failure and bladder atony with substantial urologic morbidity. Parents should be counseled accordingly and prompt urologic consultation should be included in the multidisciplinary approach to these complex patients.

Trends in Urologic Indications for Pediatric Renal Transplantation Over a 27-Year-period United Network for Organ Sharing (UNOS) Database.

OBJECTIVE: To elucidate the trends in urologic causes for renal transplant in the pediatric population using a national database. Little is known about the specific pediatric urologic conditions and resultant trends that precede renal transplantation. MATERIAL AND METHODS: We reviewed the United Network for Organ Sharing (UNOS) database for pediatric patients (<18 years old) who underwent renal transplantation from January 1988 to September 2015. We included those patients who received a renal transplant because of a urologic condition. RESULTS: Over 27 years, 7291 of 20,213 children (36%) underwent renal transplant secondary to a urologic condition. The 2 most common indications were hypoplasia/dysplasia/dysgenesis/agenesis (HDDA, 35.1%) and congenital obstructive uropathy (COU, 25.7%). The incidence of COU has increased from 18% to 30%, and the incidence of Wilms tumor has remained relatively consistent at 1.8% per year. In addition, 68% of all urologic renal transplants were performed in men compared with women. However, a higher percentage of women required transplantation because of Wilms tumor (3.1% vs 1.2%) and chronic pyelonephritis (17.6% vs 7.9%). Overall, the majority of patients (61.5%) who underwent renal transplantation were white, 18.8% Hispanic, and 15.3% black. CONCLUSION: HDDA and COU consistently have been the most common urologic indications for renal transplantation. Both are the leading causes in men, whereas HDDA and chronic pyelonephritis are predominant in women. Higher rate of renal transplant during the ages of 11-17 years is suggestive of increased burden on poorly functioning kidneys during times of adolescent growth.

Bowel preparation prior to reconstructive urologic surgery in pediatric myelomeningocele patients.

INTRODUCTION: Mechanical bowel preparation (MBP) has historically been the standard of care for patients undergoing reconstructive urologic surgery, including urinary diversion. To date, several studies have examined the role of mechanical bowel preparation in postoperative outcomes in pediatric patients undergoing augmentation cystoplasty. However, these patient populations have been heterogeneous in nature, with no studies dedicated to examining the role of MBP prior to reconstructive urologic surgery in pediatric patients with myelomenginoceles. Thus, our objective was to retrospectively assess perioperative measures and postoperative complications after reconstructive urologic surgery with or without mechanical bowel preparation in pediatric myelomeningocele patients. MATERIALS AND METHODS: From 2008 to 2013, 80 patients with myelomeningocele underwent reconstructive urologic surgery involving the use of bowel. Seventy patients underwent a preoperative MBP while 10 did not. Perioperative measures and postoperative complications for these two cohorts were assessed. RESULTS: Eighty patients with myelomeningocele were identified; 70 patients underwent MBP while 10 patients did not. There were no statistically significant differences in demographics or operative time. There were no statistically significant differences in postoperative outcomes including time to first bowel movement and time to tolerating diet. There was also no significant difference in overall complication rate; patients with MBP had 31/70 (44%) complications while 2/10 (20%) of those without MBP had complications (p = 0.18). CONCLUSION: There was no significant difference in perioperative measures and postoperative complications for patients who did not receive a mechanical bowel preparation. Our findings indicate that it is safe and warranted to perform a prospective, randomized study to better characterize the risks and benefits of preoperative bowel preparation for patients with myelomeningocele.

Percutaneous Stone Surgery in Spina Bifida Patients--Are Stone-Free Rates Worth the Risk?

PURPOSE: Percutaneous stone surgery can be challenging in spina bifida (SB) patients due to their body habitus and spinal cord anomalies. A safe surgical approach may necessitate acceptance of lower stone-free (SF) rates. We seek to determine if anatomic complexity, as measured by spinal cord curvature and torso length, is associated with SF rates after percutaneous stone surgery in SB patients. We hypothesize that increasing anatomic complexity is associated with lower SF rates following percutaneous stone surgery. METHODS: We retrospectively reviewed all cases of percutaneous nephrolithotomy (PCNL) and percutaneous cystolitholapaxy (PC) in patients with SB at our institution. We calculated individual Cobb angles for scoliosis and kyphosis and measured torso lengths to serve as surrogates of anatomic complexity. These parameters were used to test for associations between anatomic complexity and SF rates. RESULTS: A total of 32 procedures were analyzed (15 PCNL, 17 PC). SF rates for PCNL and PC were 60% and 71%, respectively. For both the PCNL and PC cohorts, there was no difference in age, preoperative stone burden, body mass index, operative time, or estimate blood loss between patients deemed SF or not stone free (NSF) after a single procedure. In the PCNL cohort, worsening scoliosis (higher Cobb angle) and lower SF rates trended toward statistical significance (43° vs. 24°, p = 0.058). In the PC cohort, increasing torso length was associated with lower SF rates (34.1 vs. 28.5 cm, p = 0.02). CONCLUSIONS: Overall SF rates were modest in this population. Cobb angle measurements of scoliosis and kyphosis as well as torso length are novel tools for objectively defining anatomic complexity in the SB population and may help predict success following stone surgery.

Clinical and Radiological Risk Factors Predicting Open Surgical Repair in Pediatric Patients With Dilating Vesicoureteral Reflux.

OBJECTIVE: To study the individual patient-related risk factors in those undergoing open corrective vesicoureteral reflux (VUR) surgery in a contemporary series. The management of VUR remains controversial, and the indications for open surgery has evolved from that of surgeon and patient preference to criteria involving breakthrough urinary tract infections and grade of VUR. MATERIALS AND METHODS: A retrospective study was performed, and patients undergoing open surgical repair for dilating VUR (grade III-V) from 2005 to 2014 were included. Characteristics of patients were determined to identify predictors of operative intervention. Statistical analysis including Fisher's exact test and multivariable logistic regression of patient demographics and independent predictors of surgery was performed using the Stata (College Station, TX) version 13 software package. RESULTS: Of the 469 patients, 351 (74.8%) underwent open intravesical ureteroneocystostomy and 118 (25.2%) were managed conservatively. Based on the multivariable analysis, age, female sex, number of febrile urinary tract infections, maximum grade of reflux, prenatal hydronephrosis, ureteral dilatation, and persistence of VUR on voiding phase of voiding cystourethrogram were strong predictors of eventual surgery. Female sex (odds ratio [OR]: 19.8), ureteral dilatation (OR: 6.2), and persistence of VUR on voiding phase (OR: 5.03) were among the strongest predictors of surgical intervention. CONCLUSION: Female sex and higher grades of VUR were the strongest predictors of eventual surgical intervention. VCUG characteristics of ureteral dilatation >7 mm and persistence of VUR on the voiding phase were also very strong predictors of eventual surgical intervention.

Transcutaneous Electrical Nerve Stimulation of the Foot: Results of a Novel At-home, Noninvasive Treatment for Nocturnal Enuresis in Children.

OBJECTIVE: To evaluate the effect of a novel at-home approach to electrical foot stimulation of peripheral tibial nerve branches on the frequency of nocturnal enuresis episodes in children. MATERIALS AND METHODS: Children aged 5 to 18 having 2 or more bedwetting episodes per week for at least 3 consecutive months were eligible. The study was a total of 6 weeks. Participants completed a baseline nighttime voiding diary during the first 2 weeks. This was followed by 2 weeks of foot stimulation for 60 minutes each night. During the stimulation period, and the following 2 weeks poststimulation, participants completed the nighttime voiding diary. RESULTS: Twenty-two patients with a mean age of 11.4 years (range 7-16) completed the study. Overall, there was a significant reduction in mean total wet nights from 9.0 ± 4.0 to 6.8 ± 4.8 during the stimulation period (P < .01) and a sustained significant reduction to 7.2 ± 5.0 wet nights during the poststimulation period (P = .02). Sixteen patients (72.7%) showed improvement of at least 1 less wet night during stimulation, demonstrating a significant improvement from a mean of 7.9 ± 3.7 to 4.8 ± 3.5 wet nights during the 2-week stimulation (P < .01) and maintained an improved mean of 5.1 ± 4.0 wet nights during the poststimulation period (P < .01). There were no adverse events experienced by any child. CONCLUSION: Transcutaneous foot stimulation is a well-tolerated, noninvasive, at-home treatment that may reduce the number of wet nights in children with nocturnal enuresis.

Predicting Spontaneous Stone Passage in Prepubertal Children: A Single Institution Cohort.

INTRODUCTION: No method currently exists for predicting which young child with a renal or ureteral stone will require surgery as opposed to pass the stone. Our goals were to analyze practice patterns at a major pediatric center and to identify factors that predicted spontaneous stone passage. METHOD: A retrospective review of all prepubertal patients (≤ 11 years) presenting to our institution from January 2005 to July 2014 with symptomatic nephrolithiasis was performed. Demographic data and stone details were reviewed, including anatomic location, size, and outcomes. Spontaneous stone passage was determined by parental report and/or stone absence on imaging obtained within 6 months after initial diagnosis. RESULTS: A total of 119 eligible patients were identified, with an average age of 88.7 months (4-143). Forty eight (40.3%) patients spontaneously passed their stone and the remaining 59.7% required endoscopic intervention. Overall, 79.0% had symptomatic presentation (flank pain, hematuria) and 39.5% of patients were obstructing stones. Symptomatic presentation was more common with ureteral (86.5%) than with renal (66.7%) stones, but was not associated with increased passage of stones in general (p-value 0.1765). Of the 48 patients who spontaneously passed stones, 11 (24.4%) were renal stones compared with 37 (50.0%) ureteral stones. The average size of spontaneously passed stones was 3.5 mm (2-8) for renal and 3.4 mm (1-7) for ureteral stones. Based on logistic regression, the single most important predictor of stone passage was stone size (p-value <0.001). The odds of passage were 3.1 times higher for ureteral stones compared with renal stones (p = 0.0070) when not controlling for size. CONCLUSION: In prepubertal patients, ureteral stones with an average size of 3.5 mm or less are more likely to pass spontaneously. Based on this information, watchful waiting is a reasonable option in clinically stable nonseptic patients with renal/ureteral stones of this size.

A multi-institutional study of perioperative and functional outcomes for pediatric robotic-assisted laparoscopic Mitrofanoff appendicovesicostomy.

BACKGROUND: Robotic techniques are increasingly being used for reconstructive procedures in the pediatric population. OBJECTIVE: The present study reported the functional and perioperative outcomes of a multi-institutional cohort of pediatric patients who underwent robotic-assisted laparoscopic Mitrofanoff appendicovesicostomy (RALMA). STUDY DESIGN: Pediatric patients who underwent RALMA at five different centers were included. Positioning is shown (Summary Figure). Demographics were gathered, and intraoperative parameters included concomitant procedures, detrusor tunnel length, estimated blood loss (EBL) and operative time. Perioperative outcomes included length of hospital stay (LOS), morphine use and 30-day complications. Outcomes were reported in terms of stomal continence and surgical revisions. RESULTS: Eighty-eight patients with a mean age of 10.4 ± 4.0 years were included in the analysis. Median follow-up was 29.5 months (IQR 11.8-45.0). Bladder augmentation was performed concomitantly in 15 (17%) patients, and bladder neck procedures in 34 (39%). Mean detrusor tunnel length was 3.9 ± 1.0 cm, EBL was 54 ± 70 ml, and operative time was 424 ± 120 min. Postoperatively, mean LOS was 5.2 ± 2.8 days. Patients who underwent concomitant augmentation had higher EBL and operative times (both P < 0.05). At 90 days, complications occurred in 26 patients (29.5%) with six Clavien grade ≥3 (6.8%). During follow-up, 11 (12.5%) patients required appendicovesicostomy revision. Regarding functional outcomes, 75 (85.2%) patients were initially continent. After additional procedures, 81 (92.0%) patients were continent at last follow-up. DISCUSSION: Compared to previous open series, initial stomal continence rates with RALMA were acceptable, with a minority of patients requiring subsequent procedures to manage complications and achieve continence. CONCLUSION: RALMA is safe and effective in a pediatric population with regard to perioperative complications and stomal continence.

Open versus minimally invasive ureteroneocystostomy: A population-level analysis.

INTRODUCTION: Open ureteroneocystostomy (UNC) is the gold standard for surgical correction of vesicoureteral reflux (VUR). Beyond single-center reports, there are few published data on outcomes of minimally-invasive (MIS) UNC. Our objective was to compare postoperative outcomes of open and MIS UNC using national, population-level data. METHOD: We reviewed the 1998-2012 Nationwide Inpatient Sample to identify pediatric (≤18 years) VUR patients who underwent either open or MIS UNC. Demographics, National Surgical Quality Improvement Program (NSQIP) complications, length of stay (LOS), and cost data were extracted. Statistical analysis was performed using weighted, hierarchical multivariate logistic regression (complications) and negative binomial regression (LOS, cost). RESULTS: We identified 780 MIS and 75,976 open UNC admissions. Compared with patients undergoing open UNC, patients who underwent MIS UNC were likely to be older (6.2 versus 4.8 years, p < 0.001), publically insured (43 versus 26%, p < 0.001), and treated in recent years (90 versus 46% after 2005, p < 0.001). MIS admissions were associated with a significantly shorter length of stay (1.0 versus 1.8 days, p < 0.001) and higher cost ($9230 versus $6,304, p = 0.002). After adjusting for patient-level confounders (age, gender, insurance, treatment year, and comorbidity), and hospital-level factors (region, bedsize, and teaching status), MIS UNC was associated with a significantly higher rate of postoperative urinary complications such as UTIs, urinary retention, and renal injury (OR 3.1, p = 0.02), shorter LOS (RR 0.8, p = 0.02), and higher cost (RR 1.4, p = 0.008). DISCUSSION: Strengths of this study are its large cohort size, long time horizon, national estimation, and cost data. Most prior studies are case-series limited to the size of the institutional cohort. Our analysis of 76,756 operative encounters revealed that open UNC continues to be performed at far greater frequency than MIS UNC, outpacing the latter modality by nearly 100:1. Children treated with MIS UNC had three times greater odds of developing postoperative urinary complications, and MIS UNC patients incurred average costs per admission that were nearly 1.5 times higher than those of children who underwent open UNC. These children were also likely to be older, publically insured, and treated in more recent years. On the other hand, patients treated with MIS UNC required substantially shorter postoperative hospitalization, with an average LOS roughly half that of open UNC cases. Limitations include the retrospective nature of the administrative database, lack of detailed patient-level data, and no available long-term postoperative outcomes. Compared with open surgery, MIS UNC was associated with shorter LOS but higher costs and possibly higher urinary complication rates.

24-Hour Urinary Parameters in Overweight and Obese Children with Urolithiasis.

PURPOSE: The increasing incidence of pediatric nephrolithiasis is a growing concern and its association with obesity continues to be an area of debate. We present data on urine chemistries of overweight/obese children compared to those with a normal body mass index and history of urolithiasis treated at a single institution in the United States, and assess risk factors. MATERIALS AND METHODS: We retrospectively identified 110 stone forming patients who underwent 24-hour urine collection and stratified them according to the Centers for Disease Control and Prevention definitions of overweight/obese (body mass index above 85th/95th percentile). Absolute urine collection quantities were compared between groups. Stone risk factors were analyzed according to Litholink® specified reference ranges. RESULTS: Compared to patients with low or normal body mass index, overweight and obese patients had lower body surface area adjusted citrate (242 mg/1.73 m(2) vs 315 mg/1.73 m(2), p = 0.03), lower urine phosphate (12 mg/kg vs 14 mg/kg, p = 0.04), lower urine magnesium (1.2 mg/kg vs 1.6 mg/kg, p = 0.01) and increased incidence of hypercalciuria (31% vs 11%, p = 0.02). Differences in urine citrate, phosphate and magnesium were not apparent when analyzing stone risk factors. There was no association between body mass index and urine pH. CONCLUSIONS: Overweight and obese stone forming children have decreased levels of urine citrate, phosphate and magnesium compared to patients with normal body mass index. The incidence of hypercalciuria is increased in overweight/obese patients. In contrast to findings in adults, there is no association between urine pH and body mass index.

Evolving Mechanisms of Injury and Management of Pediatric Blunt Renal Trauma--20 Years of Experience.

OBJECTIVE: To review 20 years of a prospectively maintained trauma database to identify changing trends in mechanisms of renal injury, demographics, and management outcomes. MATERIALS AND METHODS: Following the approval from the institutional review board, a prospectively maintained trauma database was reviewed for renal trauma patient demographics, management, and mechanisms of injury. Data were reviewed first for the entire cohort and then incrementally to identify mechanisms of injury associated with increasing frequency or grade of injury. RESULTS: A total of 228 graded renal injuries were identified from 1993 to 2013. The majority of renal injuries occurred in males (77.2%) >6 years of age (85.1%). Low grade (I-III) injuries were more common (70.6%). The most frequent mechanisms of injury identified were falls, recreational motor vehicle (RMV) accidents, bike accidents, motor vehicle collisions, and sports accidents, in descending order of frequency. RMV-related injuries have become frequent with time despite recommendations against use in the pediatric age population. Surgical intervention was rarely necessary. Over the 20 year study period, 5 nephrectomies (1.4%) were required, whereas 10 endoscopic interventions or percutaneous drainage procedures were needed (2.4%). CONCLUSION: The majority of blunt pediatric renal injuries are low grade and can be managed nonoperatively. Nephrectomy is rarely required but is indicated for hemodynamic instability refractory to resuscitation. Pediatric blunt renal trauma secondary to RMV use is increasing despite recommendations against their use in the pediatric population.