Inhibition of hypoxia-inducible factor-prolyl hydroxylation protects from cyclophosphamide-induced bladder injury and urinary dysfunction.

Disruption of the blood-urine barrier can result in acute or chronic inflammatory bladder injury. Activation of the oxygen-regulated hypoxia-inducible factor (HIF) pathway has been shown to protect mucosal membranes by increasing the expression of cytoprotective genes and by suppressing inflammation. The activity of HIF is controlled by prolyl hydroxylase domain (PHD) dioxygenases, which have been exploited as therapeutic targets for the treatment of anemia of chronic kidney disease. Here, we established a mouse model of acute cyclophosphamide (CYP)-induced blood-urine barrier disruption associated with inflammation and severe urinary dysfunction to investigate the HIF-PHD axis in inflammatory bladder injury. We found that systemic administration of dimethyloxalylglycine or molidustat, two small-molecule inhibitors of HIF-prolyl hydroxylases, profoundly mitigated CYP-induced bladder injury and inflammation as assessed by morphological analysis of transmural edema and urothelial integrity and by measuring tissue cytokine expression. Void spot analysis to examine bladder function quantitatively demonstrated that HIF-prolyl hydroxylase inhibitor administration normalized micturition patterns and protected against CYP-induced alteration of urinary frequency and micturition patterns. Our study highlights the therapeutic potential of HIF-activating small-molecule compounds for the prevention or therapy of bladder injury and urinary dysfunction due to blood-urine barrier disruption.NEW & NOTEWORTHY Disruption of the blood-urine barrier can result in acute or chronic inflammatory bladder injury. Here, we demonstrate that pharmacological inhibition of hypoxia-inducible factor (HIF)-prolyl hydroxylation prevented bladder injury and protected from urinary dysfunction in a mouse model of cyclophosphamide-induced disruption of the blood-urine barrier. Our study highlights a potential role for HIF-activating small-molecule compounds in the prevention or therapy of bladder injury and urinary dysfunction and provides a rationale for future clinical studies.

Parapelvic cyst: A rare cause of ureteropelvic junction obstruction in a pediatric patient managed with robotic cyst decortication.

INTRODUCTION: We report a case of a right parapelvic renal cyst causing intermittent ureteropelvic junction obstruction (UPJO). DIAGNOSTIC EVALUATION: A 13-year-old male was referred for right flank pain. Stone protocol CT revealed renal pelvis dilation with punctate stones. Due to concern for intermittently obstructive calculi, he underwent ureteroscopy, which was unremarkable. A diuretic renogram showed symmetric uptake with partial emptying on the right with pain after diuretic administration. In office, we potentiated a Dietl's crisis with ultrasound obtained before and after fluid intake. Comparison of ultrasounds revealed a parapelvic cyst causing calyceal dilation. He was counseled for robotic cyst decortication and possible pyeloplasty. SURGICAL CONSIDERATIONS: A robotic cyst decortication was performed. Once decorticated, the cyst base was fulgurated and pararenal fat was interposed into the cyst base. Console time was 70 min with minimal blood loss. The patient was discharged post-operative day 1. Follow-up renal ultrasound at 4 months demonstrated resolution of hydronephrosis and parapelvic cyst. CONCLUSION: Parapelvic renal cysts causing intermittent UPJO is a rare entity that may be missed on a diuretic renogram. Clinical suspicion and appropriate imaging with ultrasound or magnetic resonance imaging are useful. Robotic cyst decortication is a technically feasible approach to treat this condition.

The Utilization of an Opioid-Free Anesthetic for Pediatric Circumcision in an Ambulatory Surgery Center.

Circumcision is one of the most common urologic procedures performed at pediatric ambulatory centers. Emerging data on the short- and long-term effects of perioperative opioid administration has highlighted the importance of an opioid-free anesthetic regimen. We sought to evaluate the effectiveness of an opioid-free anesthetic in pediatric circumcision and its correlation with ambulatory surgery center efficiency. Patients, 3 years of age and younger, who underwent circumcision or circumcision revision by two surgeons pre and post introduction of an opioid-free anesthetic fast-track regimen at an outpatient surgical center were included. There were 100 patients included in this analysis, with 50 patients in each cohort. On univariate analysis, fast-tracking was associated with a decrease in median combined in-room and post-anesthesia care unit times (102.5 vs. 129.0 min, p-value < 0.001). This difference continued after multivariable analysis with an adjusted median combined in-room and post-anesthesia care unit time difference of -15.6 min (95% CI -34.2 to -12.7 min, p-value 0.018). In addition, the fast-track cohort received less intraoperative morphine equivalents without an increase in post-operative analgesic administration or change in postoperative questionnaire score. This demonstrates that opioid-free anesthesia may be used effectively in pediatric circumcision while also allowing for significant time savings for surgical centers.

Data highlighting phenotypic diversity of urine-associated Escherichia coli isolates.

This article provides a reusable dataset describing detailed phenotypic and associated clinical parameters in n=303 clinical isolates of urinary Escherichia coli collected at Vanderbilt University Medical Center. De-identified clinical data collected with each isolate are detailed here and correlated to biofilm abundance and metabolomics data. Biofilm-abundance data were collected for each isolate under different in vitro conditions along with datasets quantifying biofilm abundance of each isolate under different conditions. Metabolomics data were collected from a subset of bacterial strains isolated from uncomplicated cases of cystitis or cases with no apparent symptoms accompanying colonization. For more insight, please see "Defining a Molecular Signature for Uropathogenic versus Urocolonizing Escherichia coli: The Status of the Field and New Clinical Opportunities" [1].

Defining a Molecular Signature for Uropathogenic versus Urocolonizing Escherichia coli: The Status of the Field and New Clinical Opportunities.

Urinary tract infections (UTIs) represent a major burden across the population, although key facets of their pathophysiology and host interaction remain unclear. Escherichia coli epitomizes these obstacles: this gram-negative bacterial species is the most prevalent agent of UTIs worldwide and can also colonize the urogenital tract in a phenomenon known as asymptomatic bacteriuria (ASB). Unfortunately, at the level of the individual E. coli strains, the relationship between UTI and ASB is poorly defined, confounding our understanding of microbial pathogenesis and strategies for clinical management. Unlike diarrheagenic pathotypes of E. coli, the definition of uropathogenic E. coli (UPEC) remains phenomenologic, without conserved phenotypes and known genetic determinants that rigorously distinguish UTI- and ASB-associated strains. This article provides a cross-disciplinary review of the current issues from interrelated mechanistic and diagnostic perspectives and describes new opportunities by which clinical resources can be leveraged to overcome molecular challenges. Specifically, we present our work harnessing a large collection of patient-derived isolates to identify features that do (and do not) distinguish UTI- from ASB-associated E. coli strains. Analyses of biofilm formation, previously reported to be higher in ASB strains, revealed extensive phenotypic heterogeneity that did not correlate with symptomatology. However, metabolomic experiments revealed distinct signatures between ASB and cystitis isolates, including in the purine pathway (previously shown to be critical for intracellular survival during acute infection). Together, these studies demonstrate how large-scale, wild-type approaches can help dissect the physiology of colonization versus infection, suggesting that the molecular definition of UPEC may rest at the level of global bacterial metabolism.

Respiratory Heterogeneity Shapes Biofilm Formation and Host Colonization in Uropathogenic Escherichia coli.

Biofilms are multicellular bacterial communities encased in a self-secreted extracellular matrix comprised of polysaccharides, proteinaceous fibers, and DNA. Organization of these components lends spatial organization to the biofilm community such that biofilm residents can benefit from the production of common goods while being protected from exogenous insults. Spatial organization is driven by the presence of chemical gradients, such as oxygen. Here we show that two quinol oxidases found in Escherichia coli and other bacteria organize along the biofilm oxygen gradient and that this spatially coordinated expression controls architectural integrity. Cytochrome bd, a high-affinity quinol oxidase required for aerobic respiration under hypoxic conditions, is the most abundantly expressed respiratory complex in the biofilm community. Depletion of the cytochrome bd-expressing subpopulation compromises biofilm complexity by reducing the abundance of secreted extracellular matrix as well as increasing cellular sensitivity to exogenous stresses. Interrogation of the distribution of quinol oxidases in the planktonic state revealed that ∼15% of the population expresses cytochrome bd at atmospheric oxygen concentration, and this population dominates during acute urinary tract infection. These data point toward a bet-hedging mechanism in which heterogeneous expression of respiratory complexes ensures respiratory plasticity of E. coli across diverse host niches.IMPORTANCE Biofilms are multicellular bacterial communities encased in a self-secreted extracellular matrix comprised of polysaccharides, proteinaceous fibers, and DNA. Organization of these components lends spatial organization in the biofilm community. Here we demonstrate that oxygen gradients in uropathogenic Escherichia coli (UPEC) biofilms lead to spatially distinct expression programs for quinol oxidases-components of the terminal electron transport chain. Our studies reveal that the cytochrome bd-expressing subpopulation is critical for biofilm development and matrix production. In addition, we show that quinol oxidases are heterogeneously expressed in planktonic populations and that this respiratory heterogeneity provides a fitness advantage during infection. These studies define the contributions of quinol oxidases to biofilm physiology and suggest the presence of respiratory bet-hedging behavior in UPEC.

Three-Dimensional Printing of Surgical Clips: An In Vitro Pilot Study and Trial of Efficacy.

INTRODUCTION AND OBJECTIVE: Three-dimensional (3D) printing applications have increased over the past decade. Our objective was to test rapid prototyping of a 3D printed surgical clip for intraoperative use. MATERIALS AND METHODS: Our prototype was modeled after the 10 mm Weck® Hem-o-lok® polymer clip (Teleflex, Inc., Wayne, PA). A 3D computer-aided design model of the Hem-o-lok clip was reverse engineered using commercial microscopy and printing was done using an Objet Connex500 multijetting system (Stratasys, Eden Prairie, MN). The initial polymer was Objet VeroWhitePlus RGD835; the addition of Objet TangoBlackPlus FLX980 during the design process improved hinge flexibility. The 3D printed clips were then pressure tested on rubber Penrose tubing and compared in vitro versus commercial Hem-o-lok clips. RESULTS: Initial 3D printed clips were not functional as they split at the hinge upon closure of the clip jaws. Design changes were made to add Objet TangoBlackPlus FLX980 at the hinge to improve flexibility. Additional modifications were made to allow for clips to be compatible with the Hem-o-lok endoscopic clip applier. A total of 50 clips were tested. Fracture rate for the printed clips using a clip applier was 54% (n = 27), whereas none of the commercial Hem-o-lok clips broke upon closure. Of the 23 printed clips that closed, mean leak was at 20.7 κPa (range 4.8-42.7). In contrast, none of the commercial clips leaked, and fill continued until Penrose rupture at mean 46.2 κPa (44.8-47.6). CONCLUSIONS: This pilot study demonstrates feasibility of 3D printing functional surgical clips. However, the performance of our first generation clips is poor compared with commercial grade product. Refinement in printers and materials available may allow for customization of such printed surgical instruments that could be economically competitive to purchasing and stocking product.

A case of Fournier's gangrene necessitating total penectomy.

Fournier's gangrene is an uncommon necrotizing infection affecting the genital and perineal area. Penile involvement in particular is rare owing to its rich vascular supply. In this report, we document a case of Fournier's gangrene involving penile and urethral tissue requiring multiple debridements resulting in significant penile deformity and a non-healing wound. Eventually, the patient underwent penectomy and perineal urethrostomy creation. In this case, penectomy and perineal urethrostomy provide a functional outcome for highly refractory and complex patients with Fournier's gangrene involving penile tissue.

Robotic appendicovesicostomy revision in children: description of technique and initial results.

PURPOSE: To report our initial results of robotic appendicovesicostomy (APV) revision in children. PATIENTS AND METHODS: Three patients (median age 6 years; range 6-13) underwent robot-assisted APV surgery for bladder dysfunction because of posterior urethral valves, myelomeningocele, and traumatic spinal cord transection. Leakage developed in each patient from the APV. After failing more conservative treatments, the patients subsequently underwent robot-assisted APV revision. RESULTS: Robot-assisted APV revision was conducted at a median 14 months (range 6-34 mos) after initial surgery. Median operative time was 165 minutes (range 106-232 min), and blood loss was ≤5 mL for all patients. Intraoperative findings ranged from partial to complete separation of the APV from the bladder tunnel. APV leakage resolved for all patients at last follow-up (median 5 months; range 2-9 mos). CONCLUSION: This initial series expands the scope of robotic surgical procedures in children. Robot-assisted APV revision was technically feasible and safe in this early experience.