Ureteral Stent Placement Prior to Definitive Stone Treatment Is Associated With Higher Postoperative Emergency Department Visits and Opioid Prescriptions for Youth Having Ureteroscopy or Shock Wave Lithotripsy.

PURPOSE: Little is known about the impact of ureteral stents on youth having stone surgery. We evaluated the association of ureteral stent placement before or concurrent with ureteroscopy and shock wave lithotripsy with emergency department visits and opioid prescriptions among pediatric patients. MATERIALS AND METHODS: We conducted a retrospective cohort study of individuals aged 0-24 years who underwent ureteroscopy or shock wave lithotripsy from 2009-2021 at 6 hospitals in PEDSnet, a research network that aggregates electronic health record data from children's health systems in the United States. The exposure, primary ureteral stent placement, was defined as a stent placed concurrent with or within 60 days before ureteroscopy or shock wave lithotripsy. Associations between primary stent placement and stone-related ED visits and opioid prescriptions within 120 days of the index procedure were evaluated with mixed-effects Poisson regression. RESULTS: Two-thousand ninety-three patients (60% female; median age 15 years, IQR 11-17) had 2,477 surgical episodes; 2,144 were ureteroscopy and 333 were shock wave lithotripsy. Primary stents were placed in 1,698 (79%) ureteroscopy episodes and 33 (10%) shock wave lithotripsy episodes. Ureteral stents were associated with a 33% higher rate of emergency department visits (IRR 1.33; 95% CI 1.02-1.73) and a 30% higher rate of opioid prescriptions (IRR 1.30; 95% CI 1.10-1.53). The magnitudes of both associations were greater for shock wave lithotripsy. Results were similar for age <18 and were lost when restricted to concurrent stent placement. CONCLUSIONS: Primary ureteral stent placement was associated with more frequent emergency department visits and opioid prescriptions, driven by pre-stenting. These results support elucidating situations where stents are not necessary for youth with nephrolithiasis.

Genetic testing in children with nephrolithiasis and nephrocalcinosis.

BACKGROUND: Diagnosing genetic kidney disease has become more accessible with low-cost, rapid genetic testing. The study objectives were to determine genetic testing diagnostic yield and examine predictors of genetic diagnosis in children with nephrolithiasis/nephrocalcinosis (NL/NC). METHODS: This retrospective multicenter cross-sectional study was conducted on children ≤ 21 years old with NL/NC from pediatric nephrology/urology centers that underwent the Invitae Nephrolithiasis Panel 1/1/2019-9/30/2021. The diagnostic yield of the genetic panel was calculated. Bivariate and multiple logistic regression were performed to assess for predictors of positive genetic testing. RESULTS: One hundred and thirteen children (83 NL, 30 NC) from 7 centers were included. Genetic testing was positive in 32% overall (29% NL, 40% NC) with definite diagnoses (had pathogenic variants alone) made in 11.5%, probable diagnoses (carried a combination of pathogenic variants and variants of uncertain significance (VUS) in the same gene) made in 5.4%, and possible diagnoses (had VUS alone) made in 15.0%. Variants were found in 28 genes (most commonly HOGA1 in NL, SLC34A3 in NC) and 20 different conditions were identified. Compared to NL, those with NC were younger and had a higher proportion with developmental delay, hypercalcemia, low serum bicarbonate, hypophosphatemia, and chronic kidney disease. In multivariate analysis, low serum bicarbonate was associated with increased odds of genetic diagnosis (ß 2.2, OR 8.7, 95% CI 1.4-54.7, p = 0.02). CONCLUSIONS: Genetic testing was high-yield with definite, probable, or possible explanatory variants found in up to one-third of children with NL/NC and shows promise to improve clinical practice. A higher resolution version of the Graphical abstract is available as Supplementary information.

Antireflux Surgery at National Surgical Quality Improvement Program-Pediatric Hospitals.

PURPOSE: This study aims to examine contemporary practice patterns and compare short-term outcomes for vesicoureteral reflux procedures (ureteral reimplant/endoscopic injection) using National Surgical Quality Improvement Program-Pediatric data. MATERIALS AND METHODS: Procedure-specific variables for antireflux surgery were developed to capture data not typically collected in National Surgical Quality Improvement Program-Pediatric (eg vesicoureteral reflux grade, urine cultures, 31-60-day followup). Descriptive statistics were performed, and logistic regression assessed associations between patient/procedural factors and outcomes (urinary tract infection, readmissions, unplanned procedures). RESULTS: In total, 2,842 patients (median age 4 years; 76% female; 68% open reimplant, 6% minimally invasive reimplant, 25% endoscopic injection) had procedure-specific variables collected from July 2016 through June 2018. Among 88 hospitals, a median of 24.5 procedures/study period were performed (range 1-148); 95% performed ≥1 open reimplant, 30% ≥1 minimally invasive reimplant, and 70% ≥1 endoscopic injection, with variability by hospital. Two-thirds of patients had urine cultures sent preoperatively, and 76% were discharged on antibiotics. Outcomes at 30 days included emergency department visits (10%), readmissions (4%), urinary tract infections (3%), and unplanned procedures (2%). Over half of patients (55%) had optional 31-60-day followup, with additional outcomes (particularly urinary tract infections) noted. Patients undergoing reimplant were younger, had higher reflux grades, and more postoperative occurrences than patients undergoing endoscopic injections. CONCLUSIONS: Contemporary data indicate that open reimplant is still the most common antireflux procedure, but procedure distribution varies by hospital. Emergency department visits are common, but unplanned procedures are rare, particularly for endoscopic injection. These data provide basis for comparing short-term complications and developing standardized perioperative pathways for antireflux surgery.

Postoperative Imaging Patterns of Pediatric Nephrolithiasis: Opportunities for Improvement.

PURPOSE: Imaging following surgical intervention for nephrolithiasis is important to define operative success and ensure the absence of silent obstruction. We assessed nationwide postoperative imaging patterns in children undergoing ureteroscopy and shock wave lithotripsy. MATERIALS AND METHODS: We reviewed the MarketScan® Commercial Claims and Encounters database from 2007 to 2013 for patients 1 to 18 years old undergoing ureteroscopy or shock wave lithotripsy. We assessed imaging exposure following index procedure within 90 days as a primary analysis and 180 days as a secondary analysis of the index procedure. Univariate and multivariate statistical analyses were performed to assess factors associated with undergoing postoperative imaging. RESULTS: A total of 4,251 children met inclusion criteria, of whom 1,647 had undergone shock wave lithotripsy and 2,604 had undergone ureteroscopy. Postoperative imaging was performed in 57.5% of the cohort, with a higher proportion of children undergong imaging following shock wave lithotripsy compared to ureteroscopy (73% vs 47.8%, p <0.001). Noncomputerized tomographic imaging modalities were most common following ureteroscopy (70.8%) and shock wave lithotripsy (84.6%). Younger children and those with complex medical conditions or complicated postoperative courses were more likely to undergo followup imaging. Computerized tomography was more commonly used in older children and females. At 180-day followup 63% of the cohort had undergone any imaging, again more frequently following shock wave lithotripsy (77.0%) vs ureteroscopy (45.0%). CONCLUSIONS: A large percentage of children with nephrolithiasis do not undergo followup imaging after shock wave lithotripsy, and even fewer undergo imaging after ureteroscopy. Most followup imaging is done within 90 days of surgery. Further work is needed to define appropriate postoperative imaging practices in this population.

Laparoscopic heminephrectomy for duplex system: observed difference in outcomes between upper and lower pole resections.

INTRODUCTION: Renal duplication is a relatively common congenital abnormality of the urinary tract, but symptomatic duplex kidney is a rare presentation in adults. Traditionally, the treatment of choice for poorly functioning moiety has been heminephrectomy. There is extensive literature detailing the outcomes of minimally invasive upper pole heminephrectomy, but comparatively little published regarding lower pole resection, especially in adult patients. We present a series of 13 patients who underwent minimally invasive heminephrectomy for duplex kidney. MATERIALS AND METHODS: Over a 6 year period (2011-2017) 13 patients at a single center underwent laparoscopic heminephrectomy for symptomatic duplex kidney with a poorly functioning moiety. A retrospective review of case notes and imaging was undertaken. RESULTS: Eight and 5 patients underwent upper and lower pole heminephrectomies, respectively. Laparoscopic transperitoneal approach was utilized in all cases. Median length of stay was 2 days (range 1 to 16 days). In the upper pole cohort, one patient had a postoperative infection requiring IV antibiotics. In the lower pole cohort by contrast, there were three major complications (60%). Conversion to complete nephrectomy was necessary in one case; one patient had urinary leakage requiring selective embolization and one patient required a second operation to resect remnant calyces. Furthermore, two patients (40%) developed late recurrence of symptoms. CONCLUSIONS: Symptomatic duplex kidney is a rare presentation in adults. In our experience, heminephrectomy for non-functioning renal unit is safe and reproducible in experienced hands with no major complications and resolution of symptoms in the majority of patients. We have, however, observed a higher complication rate in those undergoing resection of a lower pole moiety. Alternative management such as uretero-ureterostomy should be considered in these cases.

Multi-Institutional Review of Outcomes and Complications of Robot-Assisted Laparoscopic Extravesical Ureteral Reimplantation for Treatment of Primary Vesicoureteral Reflux in Children.

PURPOSE: Robot-assisted laparoscopic extravesical ureteral reimplantation has been proposed as a minimally invasive alternative to open ureteral reimplantation for correcting primary vesicoureteral reflux in children. However, in the current literature there are conflicting data regarding the safety and efficacy of this approach. Amid ongoing debate we analyzed outcomes and complications from this procedure in a large multi-institutional cohort. MATERIALS AND METHODS: We reviewed the records of children who underwent robot-assisted laparoscopic extravesical ureteral reimplantation at 9 academic centers from 2005 to 2014. Radiographic failure was defined as persistent vesicoureteral reflux on postoperative voiding cystourethrogram or radionuclide cystogram. Complications were graded using the Clavien-Dindo scale. RESULTS: A total of 260 patients (363 ureters) underwent robot-assisted laparoscopic extravesical ureteral reimplantation for primary vesicoureteral reflux during the study period. The cohort included 90 patients with either duplex ureter (42), failed endoscopic treatment (40) or concomitant diverticulectomy (8). Of the 280 ureters with postoperative voiding cystourethrogram or radionuclide cystogram available radiographic resolution was seen in 246 (87.9%). There were 25 complications overall (9.6%), with 7 grade 3 complications (2.7%) and no grade 4 or 5 complications. Four patients (3.9%) had transient urinary retention following bilateral reimplantation. CONCLUSIONS: Robot-assisted laparoscopic extravesical ureteral reimplantation has a low complication rate consistent with published series of open ureteral reimplantation. Radiographic success rates are approaching those of the open procedure but continue to fall short of the gold standard approach. These findings necessitate critical thinking regarding potential technique improvements and further prospective investigation into the efficacy of this procedure.

The intestinal microbiome of children with initial and recurrent nephrolithiasis: A pilot study and exploratory analysis.

INTRODUCTION: Kidney stone disease in children is rising disproportionate to the general population, representing a disease population with a distinct biological mechanism as compared to adults. Factors influencing recurrent kidney stone disease in children are poorly characterized and the associations of the intestinal microbiome within sub-populations of kidney stone formers, however, are not well described. We evaluated a pilot cohort of children with nephrolithiasis comparing patients based on recurrent kidney stone episodes and abnormal 24-h urinary parameters, with dual aims to compare the microbiome signal in children with initial and recurrent nephrolithiasis and to explore additional associations in microbiome composition and diversity within this population. METHODS: Children aged 6-18 with a history of nephrolithiasis, without an active ureteral calculus or antibiotic exposure within 30 days of study entry were eligible to participate. All participants had a 24-h urine study within 6 months of study entry and provided a fecal sample. Microbiome samples were analyzed using 16S ribosomal DNA sequencing techniques for alpha and beta diversity comparing initial and recurrent stone formers as well as microbiome multivariate association (MaAsLin2) to determine differentially abundant taxa. Shotgun sequencing reads were aligned to custom oxidase degradation and butyrate production gene databases (5 databases total). Comparisons for MaAsLin2 and shotgun metagenomics, normalized to sequencing depth, were based on stone recurrence, sex, hypercalcuria (≤4 mg/kg/day), hyperoxaluria (≥45 mg/1.73 m2), and hypocitraturia (<310 mg/1.73 m2 [females] or < 365 mg/1.73 m2 [males]). RESULTS: A total of 16 enrolled children provided samples sufficient for analyses, including 9 girls and 7 boys, of whom 5 had experienced recurrent kidney stone events. Three participants had hypercalcuria, 2 had hyperoxaluria, and 4 had hypocitraturia. Comparisons of Formyl-CoA transferase between index and recurrent urinary stone disease revealed a trend towards higher mean abundance of the gene in initial stone formers (0.166% vs 0.0343%, p = 0.2847) (Summary Figure), while trends toward lower biodiversity were also noted in the recurrent stone cohort on both Faith (p = 0.06) and Shannon (p = 0.05) indices. Exploratory analyses found Eubacterium siraeum to be significantly greater in relative abundance in children with documented hypercalciuria (p = 0.001). DISCUSSION: Our pilot study demonstrates possible signals in both microbial diversity and oxalate gene expression, both of which are lower in recurrent pediatric kidney stone patients. These findings warrant further investigation as a potential diagnostic marker for future kidney stone events.

A Systematic Scoping Review of Comparative Effectiveness Studies in Kidney Stone Disease.

OBJECTIVE: To review the status of comparative effectiveness studies for kidney stone disease with focus on study outcome, type, population, time trends, and patient-centered approaches. METHODS: A systematic scoping review was performed for articles published between January 1, 2005, and March 30, 2021, using keywords relevant to kidney stone disease. Studies published in English that compared two or more alternative methods for prevention, diagnosis, treatment, monitoring, or care delivery were included. Two reviewers independently reviewed abstracts and an arbitrator resolved discrepancies. Nine reviewers abstracted information from full-length studies. Descriptive statistics were summarized, and linear regression was performed to evaluate temporal trends of study characteristics. RESULTS: We reviewed 1773 abstracts and 707 full-length manuscripts focused on surgical intervention (440); medical expulsive therapy (MET) (152); analgesic control (80); and homeopathic, diagnostics, and/or prophylaxis (84). Randomized controlled trials were common across all outcome categories, including surgery (41.6%), MET (60.2%), analgesic control (81.3%), homeopathic (41.2%), diagnostic (47.6%), and prophylaxis (49.1%). Patient-reported outcomes were utilized in 71.7% and 95% of MET and analgesic control studies, respectively, but in the minority of all other study themes. Over time, meta-analyses and multicenter studies increased [P < .001]. CONCLUSION: Surgical and MET themes dominate published comparative literature in kidney stone disease. There is substantial variation in use of patient-reported outcomes across surgical themes. Multicentered studies and those generating higher level evidence have increased over time but opportunities exist to improve collaborative, high-quality, and patient-centered research in kidney stone disease.

Surgeon, and Institution Characteristics Associated Surgical Preferences in the Pediatric KIDney Stone Care Improvement Network.

OBJECTIVE: To reveal barriers and opportunities to implement evidence for the management of pediatric kidney stone disease, we determined surgeon and institutional factors associated with preferences for the type of surgical intervention for kidney and ureteral stones. METHODS: We conducted a cross-sectional study of urologists participating in the Pediatric KIDney Stone Care Improvement Network (PKIDS) trial. Questionnaires ascertained strengths of urologists' preferences for types of surgery as well as characteristics of participating urologists and institutions. The outcome was the strength of preferences for ureteroscopy, shockwave lithotripsy, and percutaneous nephrolithotomy for four scenarios for which two alternative procedures are recommended by the AUA guidelines: (1) 2 cm kidney stone, (2) 9 mm proximal ureteral stone, (3) 1.5 cm lower pole kidney stone, (4) 1 cm nonlower pole kidney stone. Principal component analysis was performed to identify unique clusters of factors that explain surgical preferences. RESULTS: One hundred forty-eight urologists at 29 sites completed surveys. Stated preferences were highly skewed except for the choice between ureteroscopy and percutaneous nephrolithotomy for a 1.5 cm kidney stone. Shockwave lithotripsy ownership and local practice patterns most frequently associated with the strength of surgeons' preferences for the type of surgery. Principal component analysis revealed that three clusters of stone, patient, and heterogenous characteristics explained 30% of the variance in preferences. CONCLUSION: There is wide variation in the strengths of preferences for surgical interventions supported by current guidelines that are partially explained by surgeon and institutional characteristics. These results reveal opportunities to develop strategies for guidelines that consider real-world drivers of care.

The distal left Malone antegrade continence enema--is it better?

PURPOSE: The Malone antegrade continence enema is used for refractory fecal dysfunction in the pediatric neuropathic population. While various locations along the colon have been described, the optimal site for achieving efficient enemas remains unknown. We reviewed our experience with the Malone antegrade continence enema procedure and investigated functional outcomes and complications associated with proximal and distal locations. MATERIALS AND METHODS: We performed an institutional review board approved, retrospective chart review of 109 consecutive MACE procedures done by a single surgeon from 2000 to 2012. Preoperative patient characteristics, intraoperative techniques and postoperative outcomes were reviewed and statistical analysis was performed. RESULTS: Included in analysis were 90 patients treated with a total of 109 MACE procedures. Average age at operation was 13.8 years. Myelomeningocele was the most common diagnosis. Most patients underwent simultaneous urinary reconstruction. Stomal complications were most common (49% of patients). We compared the outcomes of proximal (cecal) MACE in 48 cases and distal (sigmoid colon) MACE in 55. Location did not affect the overall efficiency of fecal continence. Flush time was shorter for distal than for proximal MACE stomas (37.2 vs 61.2 minutes, p <0.001). Of the patients 15 underwent a total of 20 complete MACE revisions, including 12 proximal and 6 distal MACEs. As a channel, appendix was associated with a higher but not statistically significant stomal complication rate compared to colon (42% vs 25%). CONCLUSIONS: A cecal, transverse or colonic location for MACE results in acceptable outcomes. Distal MACE is associated with significantly shorter flush time and possibly fewer stomal complications. Stomal complications remain a frustrating reality of the MACE procedure.