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Accurate measurement of post-void residual (PVR) volumes requires accurate determination of the timing of voiding, which is challenging in non-verbal patients. As a proof of principle, we sought to test the feasibility, safety and efficacy of using an enuresis alarm to indicate voiding in ten infants. Each infant was observed for 4 h with alarm in the diaper, and diapers checked every 15-30 min to confirm voiding. The alarm activated in 31 of 33 voids (93.9%). No adverse events occurred. Further work will investigate whether this approach may improve accuracy of PVR measurement.
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INTRODUCTION: Despite swift implementation of telemedicine with the coronavirus disease 2019 pandemic, there is a paucity of research on its use for management of pediatric urology patients. Specifically, there is limited knowledge and inconsistent data on the effectiveness of telemedicine for various pediatric urologic conditions. Our aim was to evaluate the efficacy of pediatric urological care provided via video visits (VVs) at a large tertiary care children's hospital. MATERIAL AND METHODS: We performed a prospective assessment of pediatric urology patients younger than 21 years who had a VV between 5/18/2022 and 5/17/2023. New patients with a testicular diagnosis were not eligible for VVs. After entering the diagnosis and submitting billing using a modifier for telemedicine, clinicians were mandated to select whether the VV allowed for: complete case management (CCM), suboptimal case management (SCM), or incomplete case management (ICM) requiring an in-person visit. Case management categorizations were analyzed according to patient pathology, visit type (i.e., new or established), and patient-centered variables including age, sex, race, insurance type, need for an interpreter, and distress score [a proxy for socioeconomic status]. RESULTS: During the one-year period, there were 3267 telemedicine patients with a median age of 9 years (IQR 3-13) and 57.0% were male. Most VVs (89.3%) were established encounters. Almost 12% of telemedicine patients had external organ pathology (EOP, e.g., phimosis), 43.0% had internal organ pathology (IOP, e.g., hydronephrosis), and 45.1% had functional urological pathology (FUP, e.g., dysfunctional voiding). Clinicians deemed 96.9%, 2.7%, and 0.5% of VVs as having CCM, SCM or ICM, respectively. Telemedicine patients with IOP or FUP were more likely to have CCM, than those with EOP (98.5% and 97.8% vs 87.1%, p < 0.0001). On multivariable analysis, patient age, pathology, and visit type were predictive of VV efficacy. DISCUSSION: Now that telemedicine use has slowed, it is necessary to evaluate and establish its optimal role in pediatric urology. Factors associated with VV efficacy included older patient age, internal organ or functional urological pathology, and established encounters. The long-term success of telemedicine requires suitable patient selection. CONCLUSIONS: Telemedicine is quite effective for the management of a wide variety of pediatric urology patients. Continued evaluation of telemedicine, including multi-institutional investigation and corroboration, is necessary for the development of evidence-based best practice guidelines regarding appropriate, safe, and effective integration of telemedicine that drives pediatric urological care forward to meet the demands of the future.
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Refluxo Vesicoureteral , Humanos , Refluxo Vesicoureteral/epidemiologia , Prevalência , CriançaAssuntos
Pesquisa em Enfermagem , Melhoria de Qualidade , Urologia , Humanos , Criança , Pediatria , Enfermagem PediátricaRESUMO
This educational article highlights the critical role of pediatric urology nursing research in improving the care of children with urological conditions. It discusses the multifaceted nature of pediatric urology nursing, addresses challenges such as limited nurse scientists and resource constraints, and highlights the need to overcome barriers to increase research involvement. The authors emphasize the importance of prioritizing research areas, the promotion of collaboration, and the provision of adequate funding and academic time for pediatric nurses to contribute to evidence-based practice, to improve patient outcomes. Furthermore, it highlights the importance of research in advancing nursing practice, shaping protocols, and advocating for the rights and needs of children with urological conditions and their families.
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Pesquisa em Enfermagem , Enfermagem Pediátrica , Melhoria de Qualidade , Humanos , Criança , Urologia , Doenças Urológicas/terapia , Doenças Urológicas/enfermagemRESUMO
In this edition of Mythbusters, we examine the premise that prevalence of vesicoureteral reflux (VUR) in children varies by race. Specifically, we consider whether there is evidence supporting the contention that VUR is more common in White children and less common in Black children. Statements regarding the lower prevalence of VUR in Black children are ubiquitous in both research papers and reviews. Many of the references cited in support of these statements do not actually support the existence of racial variation in VUR, due to uncontrolled single-arm study designs, highly selected samples at risk for bias, or simply not addressing VUR prevalence at all. There is a small group of studies which directly compared VUR prevalence among children undergoing cystography, and these studies have found VUR to be less common among Black children compared to White children. However, the results of such papers can only be considered in the context of a system in which systemic bias and racism may impact access and care delivery in profound ways. Given that race is a social construct that bears little relationship to shared genetic ancestry or underlying biological characteristics, these findings must be approached with extreme caution. The goals of pediatric urological care should be to confer equitable care to all young children regardless of race.
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Grupos Raciais , Refluxo Vesicoureteral , Criança , Humanos , Prevalência , Estados Unidos/epidemiologia , Refluxo Vesicoureteral/epidemiologia , Refluxo Vesicoureteral/diagnóstico , Negro ou Afro-Americano , BrancosRESUMO
Why and when is animal experimentation relevant? The answer to this question depends on the research question. In this short educational article we aim to raise awareness of the importance of formulating a very specific research question before choosing an animal species. An awareness of anatomical and physiological differences vis-a-vis similarities between species, will increase the potential for obtaining data that is relevant for translation to human conditions.
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Experimentação Animal , Urologia , Animais , Criança , HumanosRESUMO
When performing animal experimentation in Pediatric Urology studies, it is important to be aware of physiological differences between species and to understand when relevant disease models are available. Diseased animal models may be more relevant in many cases, rather than performing studies in healthy and normally developed animals. For example, they may be more appropriate for the study of congenital malformations, to investigate the secondary effects of prenatal urinary obstruction, to study the effect of prenatal exposure to endogenous or exogenous factors which may lead to disease, or in testing bioengineered structures. In this short educational article, we aim to describe some disease models that have been used to simulate human pathologies and how, if properly designed, these studies can lead to important new knowledge for human translation. In addition, we also highlight the importance of formulating a research question(s) before deciding on the animal experimental model and species to choose.
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Experimentação Animal , Urologia , Animais , Humanos , Criança , Modelos AnimaisRESUMO
Although investigations over the past 2 decades have improved our understanding of the natural history of vesicoureteral reflux (VUR) and helped identify those at higher risk of both VUR itself as well as its potential severe sequelae, debate exists regarding key aspects of care, including when to perform diagnostic imaging and which patients benefit from continuous antibiotic prophylaxis. Artificial intelligence and machine learning have the potential to distill large volumes of granular data into practical tools that clinicians can use to guide diagnosis and management decisions. Surgical treatment, when indicated, remains highly effective and is associated with low morbidity.
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Refluxo Vesicoureteral , Humanos , Refluxo Vesicoureteral/diagnóstico , Refluxo Vesicoureteral/terapia , Inteligência Artificial , Antibioticoprofilaxia , Progressão da DoençaRESUMO
BACKGROUND: Ureteroscopy is a common treatment for urolithiasis, but initial ureteral access is not always possible, particularly in pediatrics. Clinical experience suggests that neuromuscular conditions such as cerebral palsy (CP) may facilitate access, thus avoiding the need for pre-stenting and staged procedures. OBJECTIVE: We sought to determine if probability of successful ureteral access (SUA) during initial attempted ureteroscopy (IAU) is higher in pediatric patients with CP vs. without CP. STUDY DESIGN: We reviewed IAU cases for urolithiasis (2010-2021) at our center. Patients with pre-stenting, prior ureteroscopy, or urologic surgical history were excluded. CP was defined using ICD-10 codes. SUA was defined as scope access to urinary tract level sufficient to reach stone. Association of CP and other factors with SUA were evaluated. RESULTS: 230 patients (45.7% male, median age: 16 years [IQR: 12-18 y], 8.7% had CP) underwent IAU, with SUA in 183 (79.6%). SUA occurred in 90.0% of patients with CP vs. 78.6% of those without CP (p = 0.38). SUA was 81.7% in patients >12 years (vs. 73.8% in those <12), and the highest SUA was in those >12 years with CP (93.3%), but these differences were not statistically significant. Renal stone location was significantly associated with lower SUA (p = 0.007). Among patients with renal stone only, SUA in those with CP was 85.7% vs. 68.9% in those without CP (p = 0.33). SUA did not differ significantly by gender or BMI. CONCLUSIONS: CP may facilitate ureteral access during IAU in pediatric patients, but we were unable to show a statistically significant difference. Further study of larger cohorts may demonstrate whether CP or other patient factors are associated with successful initial access. Improved understanding of such factors would help preoperative counseling and surgical planning for children with urolithiasis.
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Paralisia Cerebral , Cálculos Renais , Ureter , Cálculos Ureterais , Urolitíase , Adolescente , Criança , Feminino , Humanos , Masculino , Paralisia Cerebral/complicações , Cálculos Renais/cirurgia , Resultado do Tratamento , Ureter/cirurgia , Cálculos Ureterais/complicações , Cálculos Ureterais/cirurgia , Ureteroscopia/métodos , Urolitíase/cirurgiaRESUMO
INTRODUCTION: Patients with penile conditions comprise a significant proportion of any pediatric urology practice, and physical examination is the mainstay of diagnosis for such conditions. While the rapid adoption of telemedicine (TM) facilitated access to pediatric urology care during the pandemic, the accuracy of TM-based diagnosis for pediatric penile anatomy and pathology has not been studied. Our aim was to characterize the diagnostic accuracy of TM-based evaluation of pediatric penile conditions by comparing diagnosis during the initial virtual visit (VV) with a subsequent in-person visit (IPV). We also sought to assess the agreement between scheduled and actual surgical procedure performed. METHODS: A single-institution prospective database of male patients less than 21 years of age who presented for evaluation of penile conditions between August 2020 and December 2021 was analyzed. Patients were included if they had an IPV with the same pediatric urologist within 12 months of the initial VV. Diagnostic concordance was based on a surgeon-reported survey of specific penile diagnoses, completed at both initial VV and follow-up IPV. Surgical concordance was assessed based on the proposed versus billed CPT code(s). RESULTS: Median age among 158 patients was 10.6 months. The most frequent VV diagnoses were penile adhesions (n = 37), phimosis (n = 26), "other" (n = 24), post-circumcision redundancy (n = 18), and buried penis (n = 14). Initial VV and subsequent IPV diagnoses were concordant in 40.5% (64/158); 40/158 (25%) had partial concordance (at least one diagnosis matched). There was no difference in age, race, ethnicity, median time between visits, or device type between patients with concordant vs. discordant diagnoses. Of 102 patients who underwent surgery, 44 had VV only while 58 had IPV prior to surgery. Concordance of scheduled versus actual penile surgery was 90.9% in those patients who only had a VV prior to surgery. Overall, surgery concordance was lower among those with hypospadias repairs vs. non-hypospadias surgery (79.4% vs. 92.6%, p = 0.05). CONCLUSION: Among pediatric patients being evaluated by TM for penile conditions, there was poor agreement between VV-based and IPV-based diagnoses. However, besides hypospadias repairs, agreement between planned and actual surgical procedures performed was high, suggesting that TM-based assessment is generally adequate for surgical planning in this population. These findings leave open the possibility that, among patients not scheduled for surgery or IPV, certain conditions might be misdiagnosed or missed entirely.
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Circuncisão Masculina , Hipospadia , Fimose , Telemedicina , Criança , Humanos , Masculino , Hipospadia/cirurgia , Pênis/cirurgia , Pênis/anatomia & histologia , Fimose/cirurgiaRESUMO
BACKGROUND: Virtual medicine has the potential to improve access for underserved populations by facilitating timely remote evaluation. However, challenges in the real-world implementation of this technology may paradoxically exacerbate health disparities. We sought to characterize families' digital access and how social determinants of health may impact virtual medicine access within pediatric urology. We hypothesized that disadvantaged socioeconomic status would be a barrier to virtual medicine access. STUDY DESIGN: A digital access screening tool was prospectively developed and launched in July 2021. Schedulers are prompted to complete this optional screening questionnaire at the time of patient intake, for video or in-person encounters. The parent is screened for access to a device and reliable internet or cellular data that could be used to participate in a video visit. These represented the primary study outcomes. A modality preference for an in-person visit, video visit, or no preference was also recorded. Patient demographics were retrospectively evaluated, and socioeconomic status was estimated using the Distressed Communities Index generated for each patient's zip code. For each zip code, the Distressed Communities Index produces a normalized, comparative distress score ranging from 0 ("prosperous") to 100 ("distressed"). RESULTS: 3885 patients were included, with median age of 5 years (IQR 1-11). Almost 74% were male, 71.3% were White, 20.9% had public insurance, and 2.9% required an interpreter. The median distress score was 14.2 (IQR 7.2-27.5). Screening revealed that 136 families (3.5%) lacked digital access. On multivariable logistic regression analysis, insurance type (p = 0.0020) and distress score (p = 0.0125) were significant predictors of digital access (Summary Table). Those patients who lacked access to a device (p < 0.0001) or reliable internet/cellular data (p < 0.0001) were more likely to prefer an in-person visit. DISCUSSION: Family screening revealed that there is a small but significant proportion of families who lack digital access, and this cohort disproportionately represents underserved communities with higher distress scores, likely reflecting lower socioeconomic status. Those families without digital access were more likely to prefer an in-person visit. Improved identification of these socially complex "at-risk" patients can assist in the development of more inclusive health care strategies. CONCLUSIONS: Despite the chance for virtual medicine to expand access for underserved populations, lack of digital tools may hinder its potential impact on health disparities in pediatric urology. Ongoing digital access screening and further studies are needed to design interventions tailored to the specific needs of our patients, allowing for more equitable pediatric urological care.
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Telemedicina , Urologia , Criança , Humanos , Masculino , Lactente , Pré-Escolar , Feminino , Estudos RetrospectivosRESUMO
PURPOSE: False-positive urine pregnancy screening tests (UPST) have been reported among patients with bowel-containing urinary reconstruction (BCUR). However, the true frequency of such inaccurate results, which have been attributed to urinary mucous or other proteins interfering with or mimicking the binding of beta-HCG in the assay, is unknown in this population. We sought to determine the incidence of false-positive pregnancy screening tests among this patient population at our institution. MATERIALS AND METHODS: Using existing databases of patients with spina bifida, bladder exstrophy, and genitourinary rhabdomyosarcoma, we identified female patients with BCUR who had UPST over a 10-year period as screening prior to procedures or imaging. Patient and test result information was recorded. RESULTS: A total of 120 patients with a history of BCUR were identified: 33 with spina bifida, 73 within the exstrophy-epispadias complex (EEC), and 14 with genitourinary rhabdomyosarcoma. Of this group, 46 patients (38%) had at least one UPST during the study period; 15 had 1 UPST, 6 had 2 UPSTs, 4 had 3 UPSTs, and 21 had greater than 3 UPSTs, for a total of 244 UPST in this cohort. UPSTs used at our institution included Sure-Vue brand and Alere brand (HCG sensitivity 20 mIU/ml). Types of BCUR included ileal enterocystoplasty in 25 patients, colon enterocystoplasty in 6, stomach enterocystoplasty in 5, composite enterocystoplasty in 7, and continent catheterizable channel alone (e.g. Yang-Monti, appendicovesicostomy) in 3 patients. Of the 244 UPSTs in patients with BCUR, zero (0%) were positive. CONCLUSIONS: Despite reports in the literature that false-positive UPST are common among patients with bowel-containing urinary diversions, we found no positive UPST among patients with BCUR in the healthcare setting. False-positive UPST in the home setting may be due to variability in sensitivity thresholds, binding agents, technical errors in test technique, kit quality control, or other factors.
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Extrofia Vesical , Doenças dos Genitais Femininos , Disrafismo Espinal , Sistema Urinário , Humanos , Feminino , Gravidez , Extrofia Vesical/diagnóstico , Extrofia Vesical/cirurgia , Bexiga Urinária/cirurgia , Disrafismo Espinal/diagnóstico , HospitaisRESUMO
PURPOSE: Nephrolithiasis (NL) affects 1 in 11 individuals worldwide, leading to significant patient morbidity. NL is associated with nephrocalcinosis (NC), a risk factor for chronic kidney disease. Causative genetic variants are detected in 11% to 28% of NL and/or NC, suggesting that additional NL/NC-associated genetic loci await discovery. Therefore, we employed genomic approaches to discover novel genetic forms of NL/NC. METHODS: Exome sequencing and directed sequencing of the OXGR1 locus were performed in a worldwide NL/NC cohort. Putatively deleterious, rare OXGR1 variants were functionally characterized. RESULTS: Exome sequencing revealed a heterozygous OXGR1 missense variant (c.371T>G, p.L124R) cosegregating with calcium oxalate NL and/or NC disease in an autosomal dominant inheritance pattern within a multigenerational family with 5 affected individuals. OXGR1 encodes 2-oxoglutarate (α-ketoglutarate [AKG]) receptor 1 in the distal nephron. In response to its ligand AKG, OXGR1 stimulates the chloride-bicarbonate exchanger, pendrin, which also regulates transepithelial calcium transport in cortical connecting tubules. Strong amino acid conservation in orthologs and paralogs, severe in silico prediction scores, and extreme rarity in exome population databases suggested that the variant was deleterious. Interrogation of the OXGR1 locus in 1107 additional NL/NC families identified 5 additional deleterious dominant variants in 5 families with calcium oxalate NL/NC. Rare, potentially deleterious OXGR1 variants were enriched in patients with NL/NC compared with Exome Aggregation Consortium controls (χ2 = 7.117, P = .0076). Wild-type OXGR1-expressing Xenopus oocytes exhibited AKG-responsive Ca2+ uptake. Of 5 NL/NC-associated missense variants, 5 revealed impaired AKG-dependent Ca2+ uptake, demonstrating loss of function. CONCLUSION: Rare, dominant loss-of-function OXGR1 variants are associated with recurrent calcium oxalate NL/NC disease.
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Nefrolitíase , Receptores Purinérgicos P2 , Humanos , Oxalato de Cálcio , Nefrolitíase/genética , Mutação de Sentido Incorreto/genética , Transportadores de Sulfato/genética , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2/metabolismoRESUMO
Objectives: To assess the viability of a hybrid clinic model combining in-person examination with video-based consultation to minimize viral transmission risk. Methods: Data were collected prospectively in a pediatric urology clinic for in-person visits from January to April 2018 ("classic") and hybrid visits from October to December 2020 of the COVID-19 pandemic ("hybrid"). Variables included provider, diagnosis, patient type, time of day, prior surgery, postoperative status, and decision-making for surgery. The primary outcome was "room time" or time in-person. The secondary outcome was "total time" or visit duration. Proportion of visits involving close contact (room time ≥15 min) was assessed. Univariate analyses were performed using the Wilcoxon rank-sum test and Fisher's exact test. Mixed models were fitted for visit approach and other covariates as fixed effects and provider as random effect. Results: Data were collected for 346 visits (256 classic, 90 hybrid). Hybrid visits were associated with less room time (median 3 min vs. 10 min, p < 0.001) but greater total time (median 13.5 min vs. 10 min, p = 0.001) as compared with classic visits. On multivariate analysis, hybrid visits were associated with 3 min less room time (95% confidence intervals [CIs]: -5.3 to -1.7, p < 0.001) but 3.8 min more total time (95% CI: 1.5-6.1, p = 0.001). Close contact occurred in 6.7% of hybrid visits, as compared with 34.8% of classic visits (p < 0.001). Conclusions: Hybrid clinic visits reduce room time as compared with classic visits. This approach overcomes the examination limitations of telemedicine while minimizing viral transmission, and represents a viable model for ambulatory care whenever close contact carries infection risk.
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COVID-19 , Telemedicina , Criança , Humanos , COVID-19/epidemiologia , Pandemias , Assistência Ambulatorial , Instituições de Assistência AmbulatorialRESUMO
PURPOSE: The thulium fiber laser is a promising new lithoptripsy technology never before studied in the pediatric population. Our center adopted the first platform in North America, the SuperPulsed thulium fiber laser (SPTF). We aimed to compare outcomes in pediatric ureteroscopy using the SPTF to those using the gold standard, low-power holmium:yttrium-aluminum-garnet (Ho:YAG) laser. MATERIALS AND METHODS: This is a retrospective, consecutive cohort study of unilateral ureteroscopy with laser lithotripsy performed in pediatric patients from 2016 to 2021 as an early adopter of the SPTF. Thirty-day complications and stone-free status, defined as the absence of a stone fragment on followup imaging within 90 days, were analyzed using logistic regression. Operative times were compared using linear regression. Propensity scores for use of SPTF were used in regression analyses to account for potential cohort imbalance. RESULTS: A total of 125 cases were performed in 109 pediatric patients: 93 with Ho:YAG and 32 with SPTF. No significant difference was noted in age (p=0.2), gender (p=0.6), stone burden (p >0.9) or stone location (p=0.1). The overall stone-free rate was 62%; 70% with SPTF and 59% with Ho:YAG. The odds of having a residual stone fragment were significantly lower with SPTF than with Ho:YAG (OR=0.39, 95% CI: 0.19-0.77, p=0.01). There was no significant difference in operative time (p=0.8). Seven (25%) complications were noted with SPTF and 19 (22%) with Ho:YAG (p=0.6). CONCLUSIONS: The SPTF laser was associated with a higher stone-free rate than the low-power Ho:YAG laser without compromising operative time and safety.
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Lasers de Estado Sólido , Litotripsia a Laser , Criança , Estudos de Coortes , Hólmio , Humanos , Lasers de Estado Sólido/uso terapêutico , Litotripsia a Laser/métodos , Estudos Retrospectivos , Túlio , Ureteroscopia/métodosRESUMO
INTRODUCTION: Judicious use of antibiotics for surgical prophylaxis is important for reducing antimicrobial resistance while preventing infectious surgical complications. In the setting of pediatric distal hypospadias repairs, it is unclear if antibiotic surgical prophylaxis is beneficial. OBJECTIVE: The purpose of this study was to compare rates of infectious complications in pediatric subjects undergoing distal hypospadias repair who received any peri-operative antibiotics to those who did not. STUDY DESIGN: This was a review of a retrospective cohort from a database of individuals undergoing hypospadias repairs evaluating whether they received peri-operative or post-operative antibiotic prophylaxis and determining the rate of infectious complications in those who did compared to those who did not receive antibiotic prophylaxis. Infectious complications were defined as surgical site infection (SSI) or urinary tract infection (UTI). RESULTS: There was no significant difference in infectious complication rates between individuals who received peri-operative parenteral antibiotic prophylaxis and those who did not. All subjects with infectious complications received post-operative oral antibiotic prophylaxis. There was one instance of C. difficile infection in a subject who received peri-operative parenteral antibiotics. DISCUSSION: Reducing antibiotic utilization without increasing infectious surgical complications is important in safely reducing antimicrobial resistance. In this study of pediatric distal hypospadias repair, peri-operative antibiotics did not demonstrate a clear benefit and post-operative oral antibiotics demonstrated no benefit in preventing infectious complications. Other studies evaluating peri- and post-operative antibiotics for pediatric hypospadias repair have also failed to demonstrate a benefit for antibiotics in preventing infections. Practitioners should reconsider the use of antibiotics in this setting. CONCLUSION: Routine antibiotic prophylaxis does not appear beneficial for preventing infectious complications following uncomplicated, stented pediatric distal hypospadias repairs.
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Clostridioides difficile , Hipospadia , Masculino , Criança , Humanos , Hipospadia/cirurgia , Hipospadia/tratamento farmacológico , Antibioticoprofilaxia , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controleRESUMO
BACKGROUND: Assessment of the ureter is a fundamental part of the radiologic evaluation of the urinary tract. Abnormal ureteral dilation warrants further investigation to assess the etiology, which includes obstruction and/or reflux. Despite this fundamental need, there are no established normative values in children based on imaging. OBJECTIVE: To provide normative values for ureteral diameter in pediatric patients with age-related ranges. MATERIALS AND METHODS: We retrospectively reviewed all magnetic resonance (MR) urography studies and chose only normal ureters for assessment. The images were analyzed on commercially available software to assess maximum internal diameter. Manual measurements were done in cases where the images were below the resolution for automated assessment. Maximum intraluminal ureteral diameters were measured in upper, mid and lower thirds and the average of the three maximum ureteral diameters was used to obtain the average widest internal ureteral diameter. Multivariable linear regression was performed to test the association between the calculated diameter and gender. Differences in sizes between the left and right ureter were assessed using paired Wilcoxon signed rank test. RESULTS: One hundred twenty-one MR urography studies were selected, which included 160 ureter units. The diameter increases progressively with age, ranging from 3.2 mm during infancy to 5.0 mm in patients older than 16 years of age. After 9 years of age, the average widest internal ureteral diameter is slightly larger in males compared to females (odds ratio [OR]=1.91, 95% confidence interval [CI] [1.63, 2.25], P<0.0001). The right ureter was slightly larger than the left (3.9 mm vs. 3.7 mm, P=0.004) among 39 patients in whom both right and left ureter units were included. The average mid ureteral diameter is widest, followed by the distal third then proximal third. CONCLUSION: We present the normative values for the average widest internal ureteral diameter based on laterality and different segments. In the pediatric population, 3.8 mm should be considered the average widest internal ureteral diameter.