Marion Schulte

Tamsulosin and Spontaneous Passage of Ureteral Stones in Children: A Multi-Institutional Cohort Study

PURPOSE Tamsulosin is associated with increased passage of ureteral stones in adults but its effectiveness in children is uncertain. We determined the association between tamsulosin and the spontaneous passage of ureteral stones in children. MATERIALS AND METHODS We performed a multi-institutional retrospective cohort study of patients 18 years or younger who presented between 2007 and 2012 with ureteral stones up to 10 mm and who were treated with tamsulosin or oral analgesics alone. The outcome was spontaneous stone passage, defined as radiographic clearance and/or patient report of passage. Subjects prescribed tamsulosin were matched with subjects prescribed analgesics alone, using nearest neighbor propensity score matching to adjust for treatment selection. Conditional logistic regression models were used to estimate the association between tamsulosin and spontaneous passage of ureteral stones, adjusting for stone size and location. RESULTS Of 449 children with ureteral stones 334 were eligible for inclusion, and complete data were available for 274 patients from 4 institutions (99 receiving tamsulosin, 175 receiving analgesics alone). Following case matching, there were no differences in age, gender, weight, height, stone size or stone location between the 99 subjects prescribed tamsulosin and the 99 propensity score matched subjects prescribed analgesics alone. In the tamsulosin cohort 55% of ureteral stones passed, compared to 44% in the analgesics alone cohort (p=0.03). In multivariate analysis adjusting for stone size and location tamsulosin was associated with spontaneous passage of ureteral stones (OR 3.31, 95% CI 1.49-7.34). CONCLUSIONS The odds of spontaneous passage of ureteral stones were greater in children prescribed tamsulosin vs analgesics alone.

Urinary NGAL Levels Correlate with Differential Renal Function in Patients with Ureteropelvic Junction Obstruction Undergoing Pyeloplasty

PURPOSE Recent investigations described the use of NGAL, a sensitive biomarker for kidney injury, in the setting of ureteropelvic junction obstruction. We prospectively evaluated urinary NGAL levels in the affected renal pelvis and bladder of children with ureteropelvic junction obstruction undergoing unilateral dismembered pyeloplasty. Our hypothesis was that higher NGAL in the kidney and bladder would correlate with decreased ipsilateral differential function. MATERIALS AND METHODS We performed a prospective cohort study in patients treated with unilateral dismembered pyeloplasty from 2010 to 2012. Urine was obtained intraoperatively from the bladder and obstructed renal pelvis. A control population of unaffected children was recruited to provide a voided bladder specimen. Bladder NGAL levels were compared between the study and control populations. We tested our study hypothesis by correlating bladder and renal pelvic NGAL levels with the differential renal function of the affected kidney. RESULTS A total of 61 patients with a median age at surgery of 1.62 years (range 0.12 to 18.7) were enrolled in the study. Median bladder NGAL was 18.6 ng/mg (range 1.4-1,650.8) and median renal pelvic NGAL was 26.2 ng/mg (range 1.2-18,034.5, p = 0.004). Median bladder NGAL was significantly higher than in controls (p = 0.004). The correlation of bladder and renal pelvic NGAL with differential renal function was r = -0.359 (p = 0.004) and r = -0.383 (p = 0.002), respectively. CONCLUSIONS Bladder NGAL is increased in children with ureteropelvic junction obstruction. Renal pelvic and bladder normalized urinary NGAL levels correlate inversely with the relative function of the affected kidney in cases of unilateral ureteropelvic junction obstruction.

Ninety-day perioperative complications of pediatric robotic urological surgery: A multi-institutional study.

BACKGROUND Robotic technology is the newest tool in the armamentarium for minimally invasive surgery. Individual centers have reported on both the outcomes and complications associated with this technology, but the numbers in these studies remain small, and it has been difficult to extrapolate meaningful information. OBJECTIVES The intention was to evaluate a large cohort of pediatric robotic patients through a multi-center database in order to determine the frequency and types of complications associated with robotic surgery for pediatric reconstructive and ablative procedures in the United States. STUDY DESIGN After institutional review board approvals at the participating centers, data were retrospectively collected (2007-2011) by each institute and entered into a RedCap(®) database. Available demographic and complication data that were assigned Clavien grading scores were analyzed. RESULTS From a cohort of 858 patients (880 RAL procedures), Grade IIIa and Grade IIIb complications were seen in 41 (4.8%); and one patient (0.1%) had a grade IVa complication. Intraoperative visceral injuries secondary to robotic instrument exchange and traction injury were seen in four (0.5%) patients, with subsequent conversion to an open procedure. Grade I and II complications were seen in 59 (6.9%) and 70 (8.2%) patients, respectively; they were all managed conservatively. A total of 14 (1.6%) were converted to an open or pure laparoscopic procedure, of which, 12 (86%) were secondary to mechanical challenges. DISCUSSION It is believed that this study represents the largest and most comprehensive description of pediatric RAL urological complications to date. The results demonstrate a 4.7% rate of Clavien Grade IIIa and Grade IIIb complications in a total of 880 cases. While small numbers make it difficult to draw conclusions regarding the most complex reconstructive cases (bladder diverticulectomy, bladder neck revision, etc.), the data on the more commonly performed procedures, such as the RAL pyeloplasty and ureteral reimplantation, are robust and more likely represent the true complication rate for these procedures when performed by highly experienced robotic surgeons. CONCLUSION Pediatric robotic urologic procedures are technically feasible and safe. The overall 90-day complication rate is similar to reports of laparoscopic and open surgical procedures. COMPLICATIONS n (%) Life threatening (IVa): 1 (0.1%) Requiring radiologic and or surgical intervention (IIIa and IIIb): 41 (4.8%) Secondary to robotic system: 4 (0.5%) Mechanical failure leading to conversion: 14 (1.6%).

Infant robot-assisted laparoscopic upper urinary tract reconstructive surgery.

OBJECTIVE Our aim was to assess the outcomes of infant robot-assisted laparoscopic (RAL) upper urinary tract reconstruction. MATERIALS AND METHODS The medical records of all infants who underwent RAL upper urinary tract reconstruction were reviewed. Patients less than 1 year of age at surgery were included. Patient demographics, intraoperative details, narcotic usage, and complications were reviewed. RESULTS Ten infants met the study criteria. There were five right and five left-sided procedures. Eight pyeloplasties (4 right, 4 left) and two ureteroureterostomies (1 right single system, 1 left duplex system) were performed. The median age was 8 months (range 3-12 months). Median weight was 7.7 kg (range 5.8-10.9 kg). Median operative time was 128 min (range 95-205 min). There was no significant blood loss or intraoperative complications. One (10%) patient received a regional block. Eight (80%) patients did not receive postoperative narcotics. Median hospital stay was 1 day (range 1-2). Median follow-up was 10 months (range 3-18 months). Complications included one urinary leak, one ileus, and one urinary tract infection. Hydronephrosis improved in all patients. CONCLUSIONS Infant RAL upper urinary tract reconstruction is technically feasible, safe, and effective. It can be applied for duplication anomalies and single system obstructions in infants.

Prospective evaluation of urinary metabolic indices in severely obese adolescents after weight loss surgery

BACKGROUND Observational studies in obese adults have found abnormal urinary metabolic indices that predispose to nephrolithiasis. Few studies have been performed in severely obese adolescents. OBJECTIVES To assess urinary stone risk factors in severely obese adolescents and in those undergoing 2 types of weight loss surgery. SETTING Childrens hospital, United States. METHODS A prospective cross-sectional study was performed to assess urinary metabolic profiles in severely obese adolescents who either have not undergone any gastrointestinal surgery or who have undergone Roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (SG). Twenty-four-hour urine collections were performed at home and evaluated at a central laboratory. Established normal reference ranges for adults were used in the analysis. A linear regression analysis was performed assessing the relationship of the study group with each of the outcomes. RESULTS A total of 55 samples were analyzed from 14 severely obese adolescents and from 17 severely obese adolescents after bariatric surgery (RYGB, 10; SG, 7). Median body mass index was similar between the RYGB and SG groups. The median 24-hour excretion of oxalate was significantly elevated in the RYGB group. Calcium and uric acid excretion and the median supersaturation of calcium oxalate, calcium phosphate, and uric acid were similar among all groups. CONCLUSIONS Elevated excretion of oxalate in the urine of severely obese adolescents and in those who have undergone RYGB may portend increased risk for kidney stone formation. Larger longitudinal studies are needed to verify these findings and to determine the clinical risk of developing stone disease in these patient populations.

Prospective multicenter study on robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV): Outcomes and complications

BACKGROUND Robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV) is a minimally invasive alternative to open surgery. We have previously reported retrospective outcomes from our study group, and herein provide an updated prospective analysis with a focus on success rate, surgical technique, and complications among surgeons who have overcome the initial learning curve. OBJECTIVE To assess the safety and efficacy of RALUR-EV in children, among experienced surgeons. DESIGN AND METHODS We reviewed our prospective database of children undergoing RALUR-EV by pediatric urologists at eight academic centers from 2015 to 2017. Radiographic success was defined as absence of vesicoureteral reflux (VUR) on postoperative voiding cystourethrogram. Complications were graded using the Clavien scale. Univariate regression analysis was performed to assess for association among various patient and technical factors and radiographic failure. RESULTS In total, 143 patients were treated with RALUR-EV for primary VUR (87 unilateral, 56 bilateral; 199 ureters). The majority of ureters (73.4%) had grade III or higher VUR preoperatively. Radiographic resolution was present in 93.8% of ureters, as shown in the summary table. Ureteral complications occurred in five ureters (2.5%) with mean follow-up of 7.4 months (SD 4.0). Transient urinary retention occurred in four patients following bilateral procedure (7.1%) and in no patients after unilateral. On univariate analysis, there were no patient or technical factors associated with increased odds of radiographic failure. DISCUSSION We report a radiographic success rate of 93.8% overall, and 94.1% among children with grades III-V VUR. In contemporary series, alternate management options such as endoscopic injection and open UR have reported radiographic success rates of 90% and 93.5% respectively. We were unable to identify specific patient or technical factors that influenced outcomes, although immeasurable factors such as tissue handling and intraoperative decision-making could not be assessed. Ureteral complications requiring operative intervention were rare and occurred with the same incidence reported in a large open series. Limitations include lack of long-term follow-up and absence of radiographic follow-up on a subset of patients. CONCLUSIONS Radiographic resolution of VUR following RALUR is on par with contemporary open series, and the incidence of ureteral complications is low. RALUR should be considered as one of several viable options for management of VUR in children.

Calcium-to-Citrate Ratio Distinguishes Solitary and Recurrent Urinary Stone Forming Children

Purpose: The prevalence of urinary stone disease is increasing in children. We previously reported a high rate of urinary metabolic abnormalities, including hypercalciuria and hypocitraturia, in stone forming children. In this study we determined whether calcium‐to‐citrate ratio could help predict those at risk for recurrent stone formation. Materials and Methods: We conducted a retrospective cohort study to assess calcium‐to‐citrate ratios in children with urolithiasis. Two 24‐hour urine collections were performed. Urinary excretions of calcium and citrate were analyzed, and calcium‐to‐citrate ratio was calculated. Patients were stratified into solitary and recurrent stone formers and compared to a control group of normal children. Results: We identified 73 solitary and 92 recurrent stone formers. Mean patient age was 13 years for both groups. Gender was well matched. A total of 29 normal children served as controls. Mean calcium‐to‐citrate ratio was 0.41 in solitary stone formers and 0.64 in recurrent stone formers (p = 0.02). Mean value in normal children (0.33) was significantly less compared to recurrent stone formers (p = 0.002) and trended lower compared to solitary stone formers (p = 0.15). The ratio was abnormally high in recurrent stone formers (70%) compared to solitary stone formers (47%, p = 0.003). Conclusions: There are significant differences in urine calcium‐to‐citrate ratios between solitary and recurrent calcium stone forming children. Solitary stone formers trended higher compared to controls. These findings may allow more precise risk stratification and treatment to prevent recurrent stone episodes.

Outpatient robotic unilateral extravesical ureteral reimplantation in the pediatric population: short-term assessment of safety

Purpose: Robotic extravesical ureteral reimplantation has been established as a viable option for surgical management of vesicoureteral reflux. Typically this procedure is associated with a hospital stay for routine postoperative care. We assessed the short-term safety of robotic unilateral extravesical ureteral reimplantation as a scheduled outpatient procedure in a pediatric population. Materials and Methods: We retrospectively studied a cohort of patients who underwent robotic extravesical ureteral reimplantation between June 2012 and January 2018. No regional blocks were performed. Patients were discharged from the postanesthesia care unit as part of a scheduled outpatient procedure without an extended stay. Postoperative outcomes included 30-day emergency room visits, readmissions to the hospital and Clavien-Dindo grade I to V complications. Results: Four male and 23 female patients were identified. Median age was 85 months (range 27 to 210) and median weight was 26 kg (13 to 97). Median robotic console time was 140 minutes (range 84 to 257). No patient required a hospital stay for management of pain. Two patients (9%) required unplanned antibiotic therapy postoperatively for bacterial cystitis and pneumonia (Clavien-Dindo grade II complications). The patient with pneumonia was diagnosed during a subsequent emergency room visit. One patient was rehospitalized on postoperative day 4 because of constipation. No Clavien-Dindo grade III or higher complication was observed in any patient. Conclusions: Robotic unilateral extravesical ureteral reimplantation is safe as an outpatient procedure in the pediatric population. Further evaluation is warranted to assess its short and long-term outcomes on a larger scale.

Preliminary report: Surgical outcomes following genitoplasty in children with moderate to severe genital atypia

INTRODUCTION Prior studies of outcomes following genitoplasty have reported high rates of surgical complications among children with atypical genitalia. Few studies have prospectively assessed outcomes after contemporary surgical approaches. OBJECTIVE The current study reported the occurrence of early postoperative complications and of cosmetic outcomes (as rated by surgeons and parents) at 12 months following contemporary genitoplasty procedures in children born with atypical genitalia. STUDY DESIGN This 11-site, prospective study included children aged ≤2 years, with Prader 3-5 or Quigley 3-6 external genitalia, with no prior genitoplasty and non-urogenital malformations at the time of enrollment. Genital appearance was rated on a 4-point Likert scale. Paired t-tests evaluated differences in cosmesis ratings. RESULTS Out of 27 children, 10 were 46,XY patients with the following diagnoses: gonadal dysgenesis, PAIS or testosterone biosynthetic defect, severe hypospadias and microphallus, who were reared male. Sixteen 46,XX congenital adrenal hyperplasia patients were reared female and one child with sex chromosome mosaicism was reared male. Eleven children had masculinizing genitoplasty for penoscrotal or perineal hypospadias (one-stage, three; two-stage, eight). Among one-stage surgeries, one child had meatal stenosis (minor) and one developed both urinary retention (minor) and urethrocutaneous fistula (major) (Summary Figure). Among two-stage surgeries, three children developed a major complication: penoscrotal fistula, glans dehiscence or urethral dehiscence. Among 16 children who had feminizing genitoplasty, vaginoplasty was performed in all, clitoroplasty in nine, external genitoplasty in 13, urethroplasty in four, perineoplasty in five, and total urogenital sinus mobilization in two. Two children had minor complications: one had a UTI, and one had both a mucosal skin tag and vaginal mucosal polyp. Two additional children developed a major complication: vaginal stenosis. Cosmesis scores revealed sustained improvements from 6 months post-genitoplasty, as previously reported, with all scores reported as good or satisfied. DISCUSSION In these preliminary data from a multi-site, observational study, parents and surgeons were equally satisfied with the cosmetic outcomes 12 months after genitoplasty. A small number of patients had major complications in both feminizing and masculinizing surgeries; two-stage hypospadias repair had the most major complications. Long-term follow-up of patients at post-puberty will provide a better assessment of outcomes in this population. CONCLUSION In this cohort of children with moderate to severe atypical genitalia, preliminary data on both surgical and cosmetic outcomes were presented. Findings from this study, and from following these children in long-term studies, will help guide practitioners in their discussions with families about surgical management.