Christina Ching

Segmental arterial mapping during pediatric robot-assisted laparoscopic heminephrectomy: A descriptive series

INTRODUCTION The incidence of innocent moiety injury during heminephrectomy is estimated to be 4-5%. This complication can have long-term consequences for the child. Selective arterial mapping (SAM) with indocyanine green (ICG)-aided near infrared fluorescence (NIRF) imaging using the Firefly™ system on the da Vinci(®) surgical robotic console has proven to be valuable in robotic partial nephrectomy for adult renal tumors. However, there is nothing in the literature for using this technique in pediatric robot-assisted laparoscopic heminephrectomy (RALHN). OBJECTIVE To present a descriptive series of children who had SAM RALHN using ICG-aided NIRF imaging. To determine the feasibility of using ICG-aided NIRF SAM during RALHN, and to study if real-time delineation of the selective arterial anatomy of the upper and lower moieties would be helpful or change the immediate outcomes of the surgery. STUDY DESIGN A descriptive series of six children who received RALHN at the present institution. RESULTS Selective arterial mapping was performed safely without toxicity or vascular complications; it did not extend the operative time and did not change the complexity of the operation. As shown in the summary table below, SAM added value by increasing safety of the operation. The individual operation cost increase of using SAM was only related to the single-use vial of ICG. DISCUSSION Inadvertent injury to the innocent moiety in pediatric heminephrectomy is seldom noted intraoperatively, and many times only becomes evident postoperatively when there is acute ischemia or a chronic reduction in renal function. Although there is no replacement for good surgical technique and judgment, SAM during RALHN is a useful real-time way of alerting the surgeon to unexpected anatomy, and possible unintended or occult injury to the innocent moiety that could have devastating short-term and long-term consequences to the child, despite immediate recovery from surgery. CONCLUSIONS This report achieved its aim of reporting the feasibility of SAM on a small descriptive series of children who had RALHN.

Inflammation Drives Renal Scarring in Experimental Pyelonephritis

Acquired renal scarring occurs in a subset of patients following febrile urinary tract infections and is associated with hypertension, proteinuria, and chronic kidney disease. Limited knowledge of histopathology, immune cell recruitment, and gene expression changes during pyelonephritis restricts the development of therapies to limit renal scarring. Here, we address this knowledge gap using immunocompetent mice with vesicoureteral reflux. Transurethral inoculation of uropathogenic Escherichia coli in C3H/HeOuJ mice leads to renal mucosal injury, tubulointerstitial nephritis, and cortical fibrosis. The extent of fibrosis correlates most significantly with inflammation at 7 and 28 days postinfection. The recruitment of neutrophils and inflammatory macrophages to infected kidneys is proportional to renal bacterial burden. Transcriptome analysis reveals molecular signatures associated with renal ischemia-reperfusion injury, immune cell chemotaxis, and leukocyte activation. This murine model recapitulates the cardinal histopathological features observed in humans with acquired renal scarring following pyelonephritis. The integration of histopathology, quantification of cellular immune influx, and unbiased transcriptional profiling begins to define potential mechanisms of tissue injury during pyelonephritis in the context of an intact immune response. The clear relationship between inflammatory cell recruitment and fibrosis supports the hypothesis that acquired renal scarring arises as a consequence of excessive host inflammation and suggests that immunomodulatory therapies should be investigated to reduce renal scarring in patients with pyelonephritis.

Cloaca reconstruction: a new algorithm which considers the role of urethral length in determining surgical planning

BACKGROUND Cloacal malformations represent a uniquely complex challenge for surgeons. The surgical approach to date has been based on the common channel (CC) length with two patient groups considered: less than or greater than 3cm, which we believe is an oversimplification. We reviewed 19 patients, referred after surgery done elsewhere. Eight had postoperative urinary complications, 3 had constant urinary leakage and had been left after surgery with a urethra <1cm, .5 with an original 3 to 5cm common channel, who had undergone total urogenital mobilization (TUM), experienced peri-operative urethral loss needing a vesicostomy, and later, a Mitrofanoff. These patients together with a review of the cloacal and urological literature led us to design a new algorithm where urethral length is a key determinant for care. METHODS We prospectively collected data on 31 consecutive cloaca patients referred to our team (2014 to 2016) and managed according to this new protocol. The CC length, urethral length, surgical technique employed, and initial outcomes were recorded. RESULTS Of 31 primary cases, CC length was 1 to 3cm in 20, 3 to 5cm in 9, and greater than 5cm in 2. In the 1 to 3cm and the 3 to 5cm groups, a urethra less than 1.5cm led us to perform an urogenital separation. We only performed a TUM if the urethra was greater than 1.5cm. Using this protocol, we performed a urogenital separation in 1 of 20 in the 1 to 3cm CC group, 6 of 9 in the 3 to 5cm CC group, and 2 of 2 in the greater than 5cm CC group. Seven patients underwent separation, who with the previous approach, would have had a TUM. Thus far, no urinary leakage or urethral loss has occurred in any patient, but follow-up is less than 3years. CONCLUSION Urethral length appears to be a vitally important component in cloacal reconstruction. A short urethra left after repair can lead to urinary leakage. A TUM done under the wrong circumstances can lead to urethral loss. We describe a new technical approach to cloacal repair which considers urethral length but recognize that long term urological outcomes will need to be carefully documented. TYPE OF STUDY Clinical cohort study with no comparative group. LEVEL OF EVIDENCE Level 4.

Intraoperative Onabotulinumtoxin-A Reduces Postoperative Narcotic and Anticholinergic Requirements After Continent Bladder Reconstruction

OBJECTIVE To determine if intradetrusor injection of onabotulinumtoxin-A (BTX-A) would reduce postoperative narcotic and anticholinergic requirements in children undergoing open continent bladder reconstruction. MATERIALS AND METHODS After institutional review board approval, we retrospectively reviewed all bladder reconstructions performed. Bladder reconstruction was defined as the following procedures in any combination: bladder neck reconstruction and sling, bladder neck closure, Mitrofanoff, Monti, or bladder augmentation. We identified 15 children who underwent reconstruction with BTX-A injection and compared these with 15 children who did not receive BTX-A. Postoperative narcotic and anticholinergic requirements were recorded as well as length of stay, time to diet, time to return of bowel function, and complications. All medications were converted to morphine mEq/kg per day or mg/kg per day to standardize for patient size and length of stay. RESULTS Thirty patients who underwent open bladder reconstruction were included. Fifteen received BTX-A injection and 15 did not. The BTX-A group required significantly less narcotic medication postoperatively compared with the no-BTX-A group (0.32 vs 0.85 morphine mEq/kg per day; P = .0002). The BTX-A group also required significantly less anticholinergic medication compared with the no-BTX-A group (0.22 vs 0.88 mg/kg per day; P = .024). There was no significant difference between the groups with respect to length of stay (98.27 vs 9.287 days; P = .34) or return of bowel function (5.53 vs 4.93 days; P = .994). Complication rate between the groups was similar (P >.99). CONCLUSION Intraoperative injection of BTX-A significantly reduced postoperative narcotic and anticholinergic requirements in patients who underwent open continent bladder reconstruction. This is an encouraging alternative treatment to manage postoperative pain with no associated risk of significant complications.

Novel role for androgen signaling in pyelonephritis

Sex differences in urinary tract infection (UTI) susceptibility and severity are known, but have historically focused on anatomic differences between males and females. Until recently, experimental UTI has been limited to female animals due to ease of transurethral bladder catheterization. Olson and colleagues have developed a model of experimental UTI independent of sex that relies on direct bladder inoculation and thus permits investigation of sex differences in UTI susceptibility. They now build upon their prior work in this model by implicating androgens as drivers of tubular invasion by uropathogenic Escherichia coli, which form luminal bacterial communities preceding renal abscess formation.

Prolonged Vaginal Bleeding in an Adolescent Secondary to a Foreign Body: Need for a Comprehensive Assessment and Complex Surgery

BACKGROUND Heavy, prolonged menstrual bleeding is common in adolescents and results from a variety of etiologies. CASE A 13-year-old, virginal girl was referred for prolonged, heavy vaginal bleeding despite combined oral contraceptive use and elected management with a levonorgestrel intrauterine device. A preprocedure exam revealed a plastic foreign body embedded in the posterior vaginal fornix, however, attempted removal in the office was unsuccessful. Subsequent computed tomography imaging of the pelvis revealed a vaginal foreign body, complex adnexal mass, and hydroureter. The patient underwent exam under anesthesia and diagnostic laparoscopy, but required conversion to exploratory laparotomy for removal of a foreign body because of vaginal perforation abutting the rectum. SUMMARY AND CONCLUSION Foreign bodies not easily removed in the outpatient setting should be considered for surgical removal with consideration of preoperative multidisciplinary coordination when imaging reveals intra-abdominal pathology, such as tubo-ovarian abscess and hydroureter.

Simultaneous Robotic-Assisted Laparoscopy for Bladder and Bowel Reconstruction

INTRODUCTION Patients with neurogenic bladder frequently also have bowel dysfunction and a simultaneous urologic and colorectal reconstruction is possible. We present our experience with combined reconstructive procedures using robot-assisted laparoscopy, and demonstrate the utility of a minimally invasive approach that considers both the bowel and bladder management of these patients. METHODS We retrospectively reviewed all patients who underwent combined bowel and urologic reconstruction at our institution since the start of our multidisciplinary robotic program. RESULTS Seven patients were identified in our cohort with a mean age of 6.4 years (3.8-10.1 years). Six patients had myelomeningocele and 1 had caudal regression. Malone appendicostomies were placed in all 7 patients. A split appendix technique was used as a conduit in 5 patients, in situ appendix in 1, and neoappendicostomy with cecal flap in 1. Six patients had a Mitrofanoff appendiceal conduit created, while 1 patient had a sigmoid colovesicostomy for urinary diversion. Five patients required bladder neck repair. One patient had stenosis of the Mitrofanoff and one patient had an anastomotic leak of the sigmoid anastomosis. The average operating time was 526 minutes (313-724 minutes). The median length of stay (LOS) was 5 days (4-7 days), excluding one outlier who suffered an anastomotic leak and had an extended LOS (50 days). All patients who underwent continent bladder reconstruction are dry on their current catheterizing regimen, 6/7 are clean with antegrade flushes. CONCLUSION Patients with neurogenic bladder often have coexisting bowel dysfunction, which provides an opportunity to reconstruct both organ systems simultaneously and achieve social urinary and bowel continence. Before committing to any intervention, the surgeon should consider both the urologic and gastrointestinal needs of the patient, and perform the needed procedures simultaneously. We describe a number of combined operations aimed at bowel and bladder management that can be performed safely using robot-assisted laparoscopy.

The uroplakin plaque promotes renal structural integrity during congenital and acquired urinary tract obstruction

Urinary tract obstruction represents a common cause of kidney injury across the human life span, resulting in chronic kidney disease and end-stage renal disease. Yet, the extent of obstructive renal damage can be heterogeneous between individuals, implying the existence of unknown mechanisms that protect against or accelerate kidney injury. In this study, we investigated the role of urothelial remodeling in renal adaptation during congenital and acquired obstruction. In the Megabladder ( Mgb-/-) model of congenital obstruction and unilateral ureteral ligation model of acute obstruction, progressive hydronephrosis is strongly associated with dynamic reorganization of the renal urothelium, which elaborates a continuous uroplakin (Upk) plaque. This led us to postulate that the Upk plaque prevents parenchymal injury during urinary tract obstruction. To test this hypothesis, we interbred Mgb-/- and Upk1b-/- mice, which lack the critical Upk1b subunit for Upk plaque formation. Upk1b-/-; Mgb-/- mice experienced an accelerated onset of bilateral hydronephrosis with severe (>67%) parenchymal loss, leading to renal failure and mortality in adolescence. To investigate the function of the renal Upk plaque during acute obstruction, we destabilized the Upk plaque by Upk1b deletion or genetically depleted Upk+ cells following unilateral ureteral obstruction. Both of these strategies accelerated renal parenchymal loss following ureteral ligation, attesting to a conserved, stabilizing role for Upk plaque deposition in the acutely obstructed kidney. In aggregate, these complementary experiments provide the first evidence that the Upk plaque confers an essential, protective adaptation to preserve renal parenchymal integrity during congenital and acquired urinary tract obstruction.

The modified Ulaanbaatar procedure: Reduced complications and enhanced cosmetic outcome for the most severe cases of hypospadias

INTRODUCTION/OBJECTIVE Proximal hypospadias is one of the most challenging conditions that pediatric urologists have to deal with. Many procedures have been devised over the years, but nothing has been proven to be the best option. Although there have been some attempts at correcting severe hypospadias in one procedure, most have advocated a staged approach. The classic approach - laying penile skin or a graft within a split glans followed by glanuloplasty at the second stage - by definition requires two operations on the glans. In the Ulaanbaatar procedure the distal glanular urethra is constructed at the first stage, allowing for a single glans procedure and thus potentially better cosmetic outcomes. The present study discusses experience with the Ulaanbaatar procedure for severe hypospadias. STUDY DESIGN The study retrospectively reviewed every child who underwent both stages of this procedure at the present institution. It reviewed age, associated diagnoses, surgical technique and outcomes. SURGICAL TECHNIQUE The first stage was analogous to a classic first-stage procedure with regard to division of the urethral plate and correction of penile curvature. However, an island flap of preputial skin was mobilized and tubularized to create the glanular urethra. No attempt was made to bridge the native meatus and this reconstructed urethra, and the remaining penile skin was placed between the two. The second stage was performed 6 months later by tubularizing the penile skin between the two meatuses. RESULTS The series consisted of 34 boys. Mean age at surgery was 18.3 months (range 6-118). Nineteen underwent evaluation for genital ambiguity at birth (56%). Thirty (88%) received pre-operative testosterone or human chorionic gonadotropin (HCG). After urethral plate transection, persistent curvature was addressed during the first stage, with dorsal plication in 12 (35%), urethral plate transection alone in six (18%) or ventral grafting with small intestinal submucosa in 16 (47%). Twenty-three boys (67%) had the neourethra tunneled through the glans, and 11 (33%) had the glans split followed by glanuloplasty. Average time between the two stages was 7 months (range 4.0-13.9). Four patients (12%) developed urethral diverticula that required repair. One developed recurrent epididymitis related to an abnormal ejaculatory duct (no stricture) and underwent vasectomy. No patient developed a fistula. Mean length of follow-up was 15.2 months (range 0.3-55.5). DISCUSSION This modification of the classic staged hypospadias repair may allow for better cosmetic outcome, since the majority of boys required no formal glanuloplasty. There were reduced complications, perhaps because the urethral defect acted like a controlled fistula, allowing for better tissue healing prior to final urethral reconstruction.

Image of the Month: Clinical Features in a Newborn with Covered Cloacal Exstrophy

Cloacal exstrophy is the most severe type of anorectal malformations that belongs to the bladder–exstrophy–epispadias complex of genitourinary malformations. Interestingly, its variant, the covered cloacal exstrophy, is often missed. The clinical findings of this variant may include an imperforate anus, low lying umbilicus, thick pubic bone, and pubic diastasis but with an intact abdominal wall. We present an interesting case of covered cloacal exstrophy with a side-by-side duplicated bladder and discuss important considerations for the time of colostomy creation in the newborn period.