Contemporary disparities in progression to orchiopexy for cryptorchidism as reported in the Pediatric Health Information System (PHIS) database.

INTRODUCTION: When evaluating the timeliness of orchiopexy for cryptorchidism, health disparities are apparent among Hispanic and African American males and those with public insurance. Since the publication of these data, the COVID-19 pandemic has stressed our healthcare system and significantly affected the provision of pediatric urology care. OBJECTIVE: We sought to assess if certain groups were disproportionately affected in progression to orchiopexy after the diagnosis of cryptorchidism during and after the pandemic in US freestanding children's hospitals. STUDY DESIGN: Using the PHIS database, pediatric patients ≤5 years who underwent orchiopexy between January 2018 and December 2022 were retrospectively analyzed. Exclusion criteria included prematurity, retractile testes, and testicular torsion. Primary outcomes were age at orchiopexy and the proportion of individuals undergoing timely orchiopexy for cryptorchidism. RESULTS: Over the study period 3140 patients ≤5 years old underwent orchiopexy for cryptorchidism. Non-Hispanic Blacks and Hispanics were significantly less likely to have timely orchiopexy and underwent orchiopexy 2.13 and 3.60 months later compared to whites (p < 0.01). As compared to pre-COVID-19, during the pandemic the proportion of patients who had timely surgery was higher and the median age was significantly lower (p = 0.01 and p < 0.01, respectively) in white patients only. Over the study period, patients with public insurance were less likely to have timely orchiopexy and underwent orchiopexy 2.94 months later (p < 0.01) than patients with private insurance. Compared to during the pandemic, post-pandemic a significantly lower proportion of publicly insured patients have since undergone timely orchiopexy (p = 0.04). Patients in the West were less likely to have timely orchiopexy and had a higher age at time of orchiopexy (p < 0.01) than other regions. However, in the West during the pandemic, the proportion of children who had timely surgery was higher compared to pre-and post-COVID-19 (p < 0.01). DISCUSSION: Overall, regardless of insurance status, race, or location, a significant proportion of patients did not undergo timely orchiopexy. During the pandemic white patients had a lower median age and an increased proportion underwent timely orchiopexy, despite the number of orchiopexies remaining constant. Disparities in the post-COVID-19 era have been further exacerbated for publicly insured patients, who a significantly lower proportion of have since undergone timely orchiopexy. Specific efforts are required across the United States to increase timely orchiopexy for all boys. CONCLUSIONS: Progression to timely orchiopexy remains low for all boys in the era surrounding COVID-19; certain groups appear to be more adversely affected.

Inter-disciplinary provider development of an online, interactive adolescent varicocele decision aid prototype.

BACKGROUND: Decision-making regarding varicocele management can be a complex process for patients and families. However, to date, no studies have presented ways to mitigate the decisional conflict surrounding varicoceles. OBJECTIVE: To facilitate a discussion among physicians in order to develop a framework of the decision-making process regarding adolescent varicocele management, which will inform the development of the first online, interactive decision aid. MATERIALS AND METHODS: Semi-structured interviews with pediatric urologists and interventional radiologists were conducted to discuss their rationale for varicocele decision-making. Interviews were audio recorded, transcribed, and coded. Key themes were identified, grouped, and then qualitatively analyzed using thematic analysis. Utilizing the common themes identified and the Ottawa Decision Support Framework, a decision aid prototype was developed and transformed into a user-friendly website: varicoceledecisionaid.com. RESULTS: Pediatric urologists (n = 10) and interventional radiologists (n = 2) were interviewed. Key themes identified included: (1) definition/epidemiology; (2) observation as an appropriate management choice; (3) reasons to recommend repair; (4) types of repair; (5) reasons to recommend one repair over another; (6) shared decision-making; and (7) appropriate counseling. With this insight, a varicocele decision aid prototype was developed that engages patients and parents in the decision-making process. DISCUSSION AND CONCLUSIONS: This is the first interactive and easily accessible varicocele decision aid prototype developed by inter-disciplinary physicians for patients. This tool aids in decision-making surrounding varicocele surgery. It can be used before or after consultation to help families understand more about varicoceles and their repair, and why intervention may or may not be offered. It also considers a patient and family's personal values. Future studies will incorporate the patient and family perspective into the decision-making aid as well as implement and test the usability of this decision aid prototype in practice and in the wider urologic community.

Does KUB play a role in the diagnosis of bladder bowel dysfunction?

INTRODUCTION: Kidney ureter bladder radiography (KUB) is widely used for the evaluation of constipation in children with bladder and bowel dysfunction (BBD); however, there is varying evidence to support its routine diagnostic use. One drawback to KUB is radiation exposure. The dangers of radiation in children are well-documented, and per As Low As Reasonably Achievable, non-beneficial radiation should be avoided. This risk is especially high in children who undergo repeated imaging in the follow up of constipation treatment. OBJECTIVE: We sought to assess the utility of KUB in diagnosing children with BBD by comparing it to four diagnostic tests and/or validated instruments: the Dysfunctional Voiding Symptom Score (DVSS), Rome IV criteria, rectal diameter on ultrasound (RD), and the Bristol Stool Form Score (BSFS). STUDY DESIGN: We prospectively enrolled a cohort of patients presenting to an academic pediatric urology practice with symptoms of BBD. Severity of stool burden on KUB (mild, moderate, or severe), RD on ultrasound (≥3.4 cm), DVSS, Rome IV, and BSFS were obtained for each patient. All imaging was interpreted by a pediatric radiologist and pediatric urologist. Primary outcomes were the association between the four diagnostic tests and KUB stool burden. Bivariate analysis of all individual variables versus KUB was performed, as well as multivariate regressions to determine if multiple measures were predictive of KUB stool burden when combined. RESULTS: Between October 2020 and May 2022, 50 patients were enrolled. All children were under the age of 18, with a median age of 8 years (IQR 3-13). 38 % were male. Median BMI-for-age-percentile was 80.8 (IQR 50.3-98.3). When comparing individual variables to KUB in bivariate analyses, it was found that RD on ultrasound is predictive of significant stool burden on KUB (p = 0.03). No other individual variables were predictive. In the multivariate analyses, no combination of tests was found to be predictive of KUB. DISCUSSION: We compared the effectiveness of four commonly used diagnostic tests in children with BBD to validate the use of KUB. In conclusion, our results support the use of RD on ultrasound as a non-radiating alternative to KUB to assess stool burden. Data also suggest that KUB for fecal load does not correlate with urinary (DVSS) or bowel (Rome IV, BSFS) symptoms in BBD, and that symptoms scores should still be used independently for diagnosis and monitoring of treatment response. CONCLUSION: In conclusion, KUB has a limited role in the diagnosis of BBD.

Open retropubic prostatectomy in a patient with bladder exstrophy for management of hematuria and urethral discharge - A case report.

Bladder exstrophy (BE) is a rare congenital disorder causing bladder and urethral malformation due to an abdominal wall embryological defect. Traditionally, BE had a poor life expectancy, but advances now offer a normal lifespan. A 57-year-old male with BE history and ureterosigmoidostomy repair presented with intractable hematuria, urethral discharge, and recurrent prostatic infections. He underwent retropubic subtotal prostatectomy without major complications, resolving urinary symptoms. Advances in BE management extend patient lifespans. This case demonstrates successful surgical management of hematuria and urethral discharge through radical prostatectomy in an adult with a history of BE.

The Assessment of TikTok as a Source of Quality Health Information on Varicoceles.

OBJECTIVE: To evaluate the quality of varicocele information on TikTok, a popular video platform that adolescent patients are now turning to as a source of medical information before visiting a doctor. METHODS: Using the key word "varicocele," we retrieved the top 225 videos listed on TikTok in May 2022. We extracted general video and engagement data. Video information was coded and analyzed for the completeness of different types of content (definition, symptoms, evaluation, management, and outcomes). The quality of consumer health information was rated using the DISCERN instrument. RESULTS: Thirty-six videos met inclusion criteria; 17 were created by general users, 16 by healthcare professionals or systems (2 by urologists), and 3 by scientific communities. Healthcare professionals had more views than non-healthcare (P = .05). The quality of health information using the DISCERN instrument was "poor" from health care professional videos and "very poor" from non-health care professionals. However, the quality of information provided by healthcare professionals was statistically better than that of non-healthcare (P< .05). Video content mainly focused on symptoms: 50% of videos from healthcare providers had some or extensive content and 41% of non-healthcare had some content. 23% of videos had misinformation. CONCLUSION: The overall quality of information for varicoceles on TikTok is not acceptable and does not meet patient needs. It is imperative that urologists create robust, accurate content, and partner with these platforms to connect users with higher quality information. TikTok users should also be mindful that information may not be medically accurate.

Epoxyeicosatrienoic acid administration or soluble epoxide hydrolase inhibition attenuates renal fibrogenesis in obstructive nephropathy.

Epoxyeicosatrienoic acids (EETs) are arachidonic acid metabolites with biological effects, including antiapoptotic, anti-inflammatory, and antifibrotic functions. Soluble epoxide hydrolase (sEH)-mediated hydrolysis of EETs to dihydroxyeicosatrienoic acids (DHETs) attenuates these effects. Recent studies have demonstrated that inhibition of sEH prevents renal tubulointerstitial fibrosis and inflammation in the chronic kidney disease model. Given the pathophysiological role of the EET pathway in chronic kidney disease, we investigated if administration of EET regioisomers and/or sEH inhibition will promote antifibrotic and renoprotective effects in renal fibrosis following unilateral ureteral obstruction (UUO). EETs administration abolished tubulointerstitial fibrogenesis, as demonstrated by reduced fibroblast activation and collagen deposition after UUO. The inflammatory response was prevented as demonstrated by decreased neutrophil and macrophage infiltration and expression of cytokines in EET-administered UUO kidneys. EET administration and/or sEH inhibition significantly reduced M1 macrophage markers, whereas M2 macrophage markers were highly upregulated. Furthermore, UUO-induced oxidative stress, tubular injury, and apoptosis were all downregulated following EET administration. Combined EET administration and sEH inhibition, however, had no additive effect in attenuating inflammation and renal interstitial fibrogenesis after UUO. Taken together, our findings provide a mechanistic understanding of how EETs prevent kidney fibrogenesis during obstructive nephropathy and suggest EET treatment as a potential therapeutic strategy to treat fibrotic diseases.NEW & NOTEWORTHY Epoxyeicosatrienoic acids (EETs) are cytochrome P-450-dependent antihypertensive and anti-inflammatory derivatives of arachidonic acid, which are highly abundant in the kidney and considered renoprotective. We found that EET administration and/or soluble epoxide hydrolase inhibition significantly attenuates oxidative stress, renal cell death, inflammation, macrophage differentiation, and fibrogenesis following unilateral ureteral obstruction. Our findings provide a mechanistic understanding of how EETs prevent kidney fibrogenesis during obstructive nephropathy and suggest that EET treatment may be a potential therapeutic strategy to treat fibrotic diseases.

Hypospadias in toddlers: a multivariable study of prognostic factors in distal to mid-shaft hypospadias and review of literature.

Background: Tubularized incised plate urethroplasty is the most common hypospadias repair technique. However, there are unanswered questions and debates about the anatomical prognostic factors affecting the repair outcomes. This study tried to address some of the problems in the studies compromising the results of the current body of literature. Methods: A prospective cohort of 101 males aged 1-3 years undergoing primary distal to mid-shaft hypospadias repair were enrolled in the study. Complications including edema, erection, inadvertent removal of the urethral stent, surgical wound infection, bladder spasm, hematoma, and hemorrhage were evaluated. Studies in the current literature were reviewed to achieve a better perspective for future investigations. Results: Persistent complications were found in 16 cases (15.8%) including fistula formation, the persistence of chordee, meatal stenosis, glans, and urethral dehiscence. The mean follow-up time was 6.6±3.4 months. In the single-variable analysis, the meatal location, the length and width of the urethral plate, and the reversible acute postoperative events were significantly associated with the complications. Furthermore, fistula formation was associated with acute surgical site infection (p<0.001). However, the multivariable regression study revealed the presurgical meatal location to be the only statistically significant factor (p=0.03). Notably, the glans diameter or glanular groove shape, urethral plate dimensions, or presence of mild chordee were not independently associated with the outcomes (p>0.05). Conclusions: Our study on the toddlers with hypospadias surgery revealed that the location of urethral meatal was the main predicting factor in the development of major complications. Furthermore, the fistula formation at the infected surgical site emphasizes the importance of postsurgical care.

Study Regarding the Optimal Dimension of Intraoral Bitewing Radiographs in Patients with Primary Dentition.

The aim of this study was to determine the optimum dimensions of a radiographic plate to allow correct visualization of dental tissues and correct fit in the oral cavity of children with deciduous dentition. A quasi-experimental clinical study was carried out in children of both sexes aged between 3 and 5 years. The study variables were the complete visualization of the dental structures, the surveillance of ischemia on soft tissues, stimulation of the gag reflex, and acceptance of the radiographic plate by the pediatric patient through a validated visual analogue scale that measures anxiety. The data obtained were subjected to a descriptive and comparative statistical analysis carried out for both study phases. A total of 80 children participated in the study. The optimal dimensions obtained for the radiographic plate were 19.5 mm in height and 27.3 mm in width. Visualization of the dental tissues during both phases was not statistically significant (p = 0.412). However, there were statistically significant differences regarding the presence of ischemia, gag reflex, and child rejection (p < 0.001). A smaller radiographic plate allows correct visualization of the coronal dental tissues without causing rejection, ischemia, or gag reflex in patients in the deciduous dentition.

Hepatic and proximal tubule angiotensinogen play distinct roles in kidney dysfunction, glomerular and tubular injury, and fibrosis progression.

Components of the renin-angiotensin system, including angiotensinogen (AGT), are critical contributors to chronic kidney disease (CKD) development and progression. However, the specific role of tissue-derived AGTs in CKD has not been fully understood. To define the contribution of liver versus kidney AGT in the CKD development, we performed 5/6 nephrectomy (Nx), an established CKD model, in wild-type (WT), proximal tubule (PT)- or liver-specific AGT knockout (KO) mice. Nx significantly elevated intrarenal AGT expression and elevated blood pressure (BP) in WT mice. The increase of intrarenal AGT protein was completely blocked in liver-specific AGT KO mice with BP reduction, suggesting a crucial role for liver AGT in BP regulation during CKD. Nx-induced glomerular and kidney injury and dysfunction, as well as fibrosis, were all attenuated to a greater extent in liver-specific AGT KO mice compared with PT-specific AGT KO and WT mice. However, the suppression of interstitial fibrosis in PT- and liver-specific AGT KO mouse kidneys was comparable. Our findings demonstrate that liver AGT acts as a critical contributor in driving glomerular and tubular injury, renal dysfunction, and fibrosis progression, whereas the role of PT AGT was limited to interstitial fibrosis progression in chronic renal insufficiency. Our results provide new insights for the development of tissue-targeted renin-angiotensin system intervention in the treatment of CKD.NEW & NOTEWORTHY Chronic kidney disease (CKD) is a major unmet medical need with no effective treatment. Current findings demonstrate that hepatic and proximal tubule angiotensinogen have distinct roles in tubular and glomerular injury, fibrogenesis, and renal dysfunction during CKD development. As renin-angiotensin system components, including angiotensinogen, are important targets for treating CKD in the clinic, the results from our study may be applied to developing better tissue-targeted treatment strategies for CKD and other fibroproliferative diseases.

Bilateral Ureterovesical Junction Obstruction Resulting in Anuria in a 3-Week-Old Infant.

Bilateral megaureter with ureterovesical junction obstruction is exceedingly rare. We present a case of a 3-week-old boy who presented in acute renal failure and found to have bilateral megaureter. He was initially decompressed with bilateral percutaneous nephrostomy tubes and once stable underwent bilateral ureterostomy. At 6 months old, renal ultrasound showed stable mild right sided hydronephrosis.

Potential role for microbial ureolysis in the rapid formation of carbonate tufa mounds.

Modern carbonate tufa towers in the alkaline (~pH 9.5) Big Soda Lake (BSL), Nevada, exhibit rapid precipitation rates (exceeding 3 cm/year) and host diverse microbial communities. Geochemical indicators reveal that carbonate precipitation is, in part, promoted by the mixing of calcium-rich groundwater and carbonate-rich lake water, such that a microbial role for carbonate precipitation is unknown. Here, we characterize the BSL microbial communities and evaluate their potential effects on carbonate precipitation that may influence fast carbonate precipitation rates of the active tufa mounds of BSL. Small subunit rRNA gene surveys indicate a diverse microbial community living endolithically, in interior voids, and on tufa surfaces. Metagenomic DNA sequencing shows that genes associated with metabolisms that are capable of increasing carbonate saturation (e.g., photosynthesis, ureolysis, and bicarbonate transport) are abundant. Enzyme activity assays revealed that urease and carbonic anhydrase, two microbial enzymes that promote carbonate precipitation, are active in situ in BSL tufa biofilms, and urease also increased calcium carbonate precipitation rates in laboratory incubation analyses. We propose that, although BSL tufas form partially as a result of water mixing, tufa-inhabiting microbiota promote rapid carbonate authigenesis via ureolysis, and potentially via bicarbonate dehydration and CO2 outgassing by carbonic anhydrase. Microbially induced calcium carbonate precipitation in BSL tufas may generate signatures preserved in the carbonate microfabric, such as stromatolitic layers, which could serve as models for developing potential biosignatures on Earth and elsewhere.

Regional anesthesia for ambulatory pediatric penoscrotal procedures.

BACKGROUND/PURPOSE: Pediatric urology procedures are amongst the most commonly performed in children. The need for proactive treatment of pain is essential for optimal patient care. Current guidelines recommend the routine use of regional anesthesia in children as appropriate unless contraindicated. Given the commonality of urologic procedures in children, it is essential to understand the indications for and the utility of regional anesthesia. METHODS: The current literature was searched using PubMed as the primary platform. Search words included 'dorsal penile nerve block,' 'pudendal nerve block,' 'ring block,' 'spinal anesthesia,' and 'caudal,' along with 'pediatric', 'circumcision,' 'hypospadias,' 'urology', and 'urological surgery' as part of the keywords of the search. RESULTS: The articles resulting from the literature search were reviewed for content, clarity and study design by two co-authors, and agreement determined the incorporation into the review. Additionally, a detailed description of study design, regional anesthetic technique, local anesthetic(s) used, and outcomes of each study referenced was incorporated into the supplemental table. CONCLUSION: Given the variance in block technique and local anesthetic choice amongst the current reported studies in the literature, it is difficult to truly compare and infer superiority of the regional anesthetic choices for ambulatory penoscrotal procedures. When choosing a regional anesthetic technique, careful consideration must be placed on block coverage, severity of expected pain and surgical duration of the procedure, type and dose of local anesthetic, as well as the patient's past medical history and anatomy. Moreover, the regional block chosen should result from a thorough preoperative discussion between the surgeon and the anesthesiologist.

Planar chromatography and immunodetection of hydrocarbons on polyvinylidene difluoride membranes.

Fast, cheap, and simple separation of lipids and hydrocarbons can currently be achieved using thin-layer chromatography. Here, we describe an alternative planar chromatographic method using polyvinylidene difluoride membranes as the stationary phase. The procedure has the same advantages of thin-layer chromatography over other expensive and time-consuming techniques, such as high-performance liquid chromatography or gas chromatography. Polyvinylidene difluoride membranes, however, also provide an immediate support for analyte development via immunodetection, are easy to manipulate, and potentially increase the performance of other detection methods. We show that polyvinylidene difluoride membranes are compatible with a variety of solvents that can migrate by capillarity and redistribute analytes between the membrane and the solvent according to their relative affinities, providing a chromatographic separation. We directly test the developed membranes by immunoblotting using anti-squalene antibodies that cross-react with acyclic isoprenoids. Separations of crude oils and plant extracts under different solvent conditions show the potential to resolve hydrocarbon group types and also to provide characteristic fingerprints of plant pigments and squalene degradation products. Polyvinylidene difluoride membranes prove useful as a stationary phase for planar chromatography and for the subsequent immunodetection of the separated compounds, providing a new and simple chromatographic technique to analyze lipids and hydrocarbons.

Directed co-evolution of interacting protein-peptide pairs by compartmentalized two-hybrid replication (C2HR).

Directed evolution methodologies benefit from read-outs quantitatively linking genotype to phenotype. We therefore devised a method that couples protein-peptide interactions to the dynamic read-out provided by an engineered DNA polymerase. Fusion of a processivity clamp protein to a thermostable nucleic acid polymerase enables polymerase activity and DNA amplification in otherwise prohibitive high-salt buffers. Here, we recapitulate this phenotype by indirectly coupling the Sso7d processivity clamp to Taq DNA polymerase via respective fusion to a high affinity and thermostable interacting protein-peptide pair. Escherichia coli cells co-expressing protein-peptide pairs can directly be used in polymerase chain reactions to determine relative interaction strengths by the measurement of amplicon yields. Conditional polymerase activity is further used to link genotype to phenotype of interacting protein-peptide pairs co-expressed in E. coli using the compartmentalized self-replication directed evolution platform. We validate this approach, termed compartmentalized two-hybrid replication, by selecting for high-affinity peptides that bind two model protein partners: SpyCatcher and the large fragment of NanoLuc luciferase. We further demonstrate directed co-evolution by randomizing both protein and peptide components of the SpyCatcher-SpyTag pair and co-selecting for functionally interacting variants.

The Resilient Child: Sex-Steroid Hormones and COVID-19 Incidence in Pediatric Patients.

Coronavirus disease-2019 (COVID-19), a disease caused by Severe Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, has become an unprecedented global health emergency, with fatal outcomes among adults of all ages in the United States, and the highest incidence and mortality in adult men. As the pandemic evolves there is limited understanding of a potential association between symptomatic viral infection and age. To date, there is no knowledge of the role children (prepubescent, ages 9-13 years) play as "silent" vectors of the virus, with themselves being asymptomatic. Throughout different time frames and geographic locations, the current evidence on COVID-19 suggests that children are becoming infected at a significantly lower rate than other age groups-as low as 1%. Androgens upregulate the protease TMPRSS2 (type II transmembrane serine protease-2), which facilitates efficient virus-host cell fusion with the epithelium of the lungs, thus increasing susceptibility to SARS-CoV-2 infection and development of severe COVID-19. Owing to low levels of steroid hormones, prepubertal children may have low expression of TMPRSS2, thereby limiting the viral entry into host cells. As the world anticipates a vaccine against SARS-CoV-2, the role of prepubescent children as vectors transmitting the virus must be interrogated to prepare for a potential resurgence of COVID-19. This review discusses the current evidence on the low incidence of COVID-19 in children and the effect of sex-steroid hormones on SARS-CoV-2 viral infection and clinical outcomes of pediatric patients. On reopening society at large, schools will need to implement heightened health protocols with the knowledge that children as the "silent" viral transmitters can significantly affect the adult populations.

Field detection of urease and carbonic anhydrase activity using rapid and economical tests to assess microbially induced carbonate precipitation.

Microbial precipitation of calcium carbonate is a widespread environmental phenomenon that has diverse engineering applications, from building and soil restoration to carbon sequestration. Urease-mediated ureolysis and CO2 (de)hydration by carbonic anhydrase (CA) are known for their potential to precipitate carbonate minerals, yet many environmental microbial community studies rely on marker gene or metagenomic approaches that are unable to determine in situ activity. Here, we developed fast and cost-effective tests for the field detection of urease and CA activity using pH-sensitive strips inside microcentrifuge tubes that change colour in response to the reaction products of urease (NH3 ) and CA (CO2 ). The urease assay proved sensitive and useful in the field to detect in situ activity in biofilms from a saline lake, a series of calcareous fens, and ferrous springs, finding relatively high urease activity in lake samples. Incubations of lake microbes with urea resulted in significantly higher CaCO3 precipitation compared to incubations with a urease inhibitor, showing that the rapid assay indicated an on-site active metabolism potentially mediating carbonate precipitation. The CA assay, however, showed less sensitivity compared to the urease test. While its sensitivity limits its utility, the assay may still be useful as a preliminary indicator given the paucity of other means for detecting CA activity in the field. Field urease, and potentially CA, activity assays complement molecular approaches and facilitate the search for carbonate-precipitating microbes and their in situ activity, which could be applied toward agriculture, engineering and carbon sequestration technologies.

A novel urinary biomarker protein panel to identify children with ureteropelvic junction obstruction - A pilot study.

INTRODUCTION AND OBJECTIVE: Reliable urinary biomarker proteins would be invaluable in identifying children with ureteropelvic junction obstruction (UPJO) as the existing biomarker proteins are inconsistent in their predictive ability. Therefore, the aim of this study was to identify consistent and reliable urinary biomarker proteins in children with UPJO. METHODS: To identify candidate biomarker proteins, total protein from age-restricted (<2 years) and sex-matched (males) control (n = 22) and UPJO (n = 21) urine samples was analyzed by mass spectrometry. Proteins that were preferentially identified in UPJO samples were selected (2-step process) and ranked according to their diagnostic odds ratio value. The top ten proteins with highest odds ratio values were selected and tested individually by ELISA. The total amount of each protein was normalized to urine creatinine and the median with interquartile ranges for control and UPJO samples was determined. Additionally, fold change (UPJO/Control) of medians of the final panel of 5 proteins was also determined. Finally, we calculated the average + 3(SD) and average + 4(SD) values of each of the 5 proteins in the control samples and used it as an arbitrary cutoff to classify individual control and UPJO samples. RESULTS: In the first step of our selection process, we identified 171 proteins in UPJO samples that were not detected in the majority of the control samples (16/22 samples, or 72.7%). Of the 171 proteins, only 50 proteins were detected in at least 11/21 (52.4%) of the UPJO samples and hence were selected in the second step. Subsequently, these 50 proteins were ranked according to the odds ratio value and the top 10 ranked proteins were validated by ELISA. Five of the 10 proteins - prostaglandin-reductase-1, ficolin-2, nicotinate-nucleotide pyrophosphorylase [carboxylating], immunoglobulin superfamily-containing leucine-rich-repeat-protein and vascular cell adhesion molecule-1 were present at higher levels in the UPJO samples (fold-change of the median protein concentrations ranging from 2.9 to 9.4) and emerged as a panel of biomarkers to identify obstructive uropathy. Finally, the order of prevalence of the 5 proteins in UPJO samples is PTGR1>FCN2>QPRT>ISLR>VCAM1. CONCLUSION: In summary, this unique screening strategy led to the identification of previously unknown biomarker proteins that when screened collectively, may reliably distinguish between obstructed vs. non-obstructed infants and may prove useful in identifying informative biomarker panels for biological samples from many diseases.