Reducing fistula rate in hypospadias repair: A comparative study between standard tubularized incised plate repair and incorporation of a layer of spongiosum tissue.

INTRODUCTION: The most prevalent complication in hypospadias repair is fistula formation. Adhering to the principle of providing urethroplasty coverage to mitigate fistula occurrence, we implemented a modification by integrating a spongiosum layer between the urethroplasty and the dartos flap. Our hypothesis posited that this approach would result in a reduced fistula formation rate. METHODS: This study is a comparative analysis involving patients under 18 years of age who underwent primary hypospadias repair. The cases were allocated into two groups. In the study group, in addition to performing tubularized incised plate (TIP) repair, a spongiosum layer harvested from both sides of the urethra was used to cover the urethroplasty (modification of the Y-to-I urethroplasty). The control group underwent a standard TIP repair. The primary outcome was to assess urethrocutaneous fistula formation. Secondary outcomes included evaluating the development of meatal stenosis and glans dehiscence, along with assessing cosmetic results by the Hypospadias Objective Penile Evaluation (HOPE) score. RESULTS: Overall, 154 hypospadias cases were included in the study. Eighty-seven patients (56%) were allocated to the study group, and 67 (44%) were allocated to the control group. Urethrocutaneous fistula developed in 3 (3.4%) and 11 (16.4%) patients in the study and control group, respectively (p = 0.006). Glans dehiscence occurred in 2 (2.3%) patients in the study group and 4 (6%) patients in the control group (p = 0.198). Meatal stenosis was observed in 4 (4.6%) patients in the study group and 5 (7.5%) patients in the control (p = 0.452). The mean HOPE score was 59 in both groups (p = 0.36). DISCUSSION: This study details our encounters with the novel modification and compares the results with standard TIP. Our data suggest that adding a layer of spongiosum tissue over the urethroplasty reduces the complication of urethrocutaneous fistula without increasing the occurrence of dehiscence, significant meatal stenosis, or compromising cosmetic outcomes. CONCLUSION: We advocate for implementing the described surgical modification as a viable option for hypospadias repair.

Use of Validated Questionnaires to Predict Cosmetic Outcomes of Hypospadias Repair.

INTRODUCTION: Hypospadias is a syndrome of penile maldevelopment. The primary goal of hypospadias surgery is to create a penis with normal appearance and function. Historically, the outcome of hypospadias repair has been assessed based on the need for reoperation due to urethroplasty complications (UC), including fistula formation, dehiscence, meatal stenosis, or development of a urethral stricture. The Glans-Urethral Meatus-Shaft (GMS) score is a standardized tool to predict UC. Analysis of the cosmetic outcomes of hypospadias repair based on the appearance of the reconstructed penis has been validated, and standardized scores have been published. The Hypospadias Objective Penile Evaluation (HOPE) score is a validated questionnaire used to assess postoperative cosmetic outcomes. Although predictors of surgical outcomes and UC have been well documented, predictors of optimal cosmetic outcomes are lacking in the literature. Furthermore, reoperation due to cosmetic considerations has been poorly reported. OBJECTIVE: To identify predictors of cosmetic outcomes after hypospadias repair and to assess the reoperation rate according to cosmetic considerations. MATERIALS AND METHODS: This prospective cohort study included 126 boys who underwent primary hypospadias repair. The severity of hypospadias, degree of penile curvature, glans width, preoperative HOPE, and GMS scores were documented. The standard technique for single-stage repairs, the tubularized incised plate urethroplasty, was performed. The primary endpoint was cosmetic outcomes evaluated by the HOPE score questionnaire six months postoperatively. Optimal cosmetic results were defined by HOPE scores ≥ 57. RESULTS: The study population consisted of the following cases: 87 (69%) subcoronal, 32 (25%) shaft, and 7 (6%) proximal hypospadias. Among the study participants, 102 boys (81%) had optimal cosmetic results (HOPE ≥ 57), and 24 boys (19%) had surgeries with suboptimal cosmetic outcomes (HOPE < 57). Ancillary procedures were performed in 21 boys (16%), of which 14 (11%) were solely for cosmetic considerations, and 7 were secondary to UC. Using the Receiver Operating Characteristic analysis of potential predictors of optimal cosmetic outcomes, the preoperative HOPE score had the highest area under the curve (AUC = 0.79; 95% CI 0.69-0.89, p < 0.001). After multivariable analysis, the degree of penile chordee (p = 0.013), glans width (p = 0.003), GMS score (p = 0.007), and preoperative HOPE score (p = 0.002) were significant predictors of cosmetic outcomes. Although meatal location predicted suboptimal cosmetic results in univariate analysis, it was not a factor in multivariable analysis. CONCLUSIONS: Over 80% of boys undergoing hypospadias repair achieved optimal cosmetic outcomes. More than 10% of cases underwent ancillary procedures, secondary solely to cosmetic considerations. Predictors of optimal cosmetic outcomes after hypospadias surgery included degree of chordee, glans width, and preoperative HOPE and GMS scores, which were the best predictors of satisfactory cosmetic results. Although meatal location is the main predictor of UC, it was not a predictor for cosmetic outcomes. Factors affecting cosmetic outcomes should be clearly explained to parents during the preoperative consultation.

Repositioning of Ureteropelvic Junction in Robot-assisted Laparoscopic Pyeloplasty.

OBJECTIVE: To describe the technique of ureteropelvic junction (UPJ) repositioning in robot-assisted dismembered pyeloplasty as a modified approach during which the UPJ is brought to a new location to facilitate the anastomosis. MATERIALS AND METHODS: Retrospective review of pediatric and adult cases of robot-assisted laparoscopic pyeloplasty performed between the years 2016 and 2022. In a select group of patients, repositioning of the UPJ was performed. Demographic data, surgical and post-surgical outcomes were compared to a group that underwent classical Anderson-Hynes (AH) dismembered pyeloplasty. RESULTS: Overall, 70 patients underwent robot-assisted laparoscopic dismembered pyeloplasty and were included in the study, with 15 in the repositioning group and 55 in the AH group. The median age of patients included was 26 months (interquartile range (IQR) 7-203). Median operative time was 140 minutes (IQR 129-192) and 170 minutes (IQR 135-207) for the repositioning and AH group, respectively. The indications for UPJ repositioning were high UPJ insertion (n = 8), crossing vessel (n = 5), and renal malformations (n = 2). Clinical significance was shown in the Society of Fetal Urology classification and split renal function postoperatively, respectively (P <.001; P <.01). Postoperatively, both groups showed improvement in anterior posterior diameter (APD) and diuretic T1/2 (P = 0.48). There was 1 case of surgical failure requiring revisional surgery in the repositioning group (6.6%) and 3 in the AH group (5.5%) (P >.05). Overall, there were 3 cases of Clavien-Dindo Grade 3 complications, all in the AH group (2 cases of urine leak from anastomosis, 1 case of port side hernia). CONCLUSION: Repositioning of the UPJ is optional in cases when the obstructed UPJ is in a suboptimal anatomical position.

Laparoscopic Ureteral Reimplantation after Failed Open Surgery: Incorporating the Psoas Hitch Maneuver for Sufficient Tunnel Length.

BACKGROUND: Failure after open ureteral reimplantation has been reported to occur in 2 to 7% of cases. While a second open reconstructive surgery is appropriate in most cases, there are data suggesting similar outcomes utilizing the laparoscopic approach. The objective of this study is to describe a modification and report our experience with laparoscopic ureteral reimplantation after failed open reimplantation reinforced with a psoas hitch. MATERIALS AND METHODS: A retrospective review of pediatric patients who underwent laparoscopic ureteral reimplantation after failed open surgery between September 2012 and April 2018 at three different academic centers was performed. Patient demographics, surgical indications, complications, and outcomes were reviewed. Either ipsilateral ureteral reimplantation with a combined intravesical and extravesical approaches or a cross-trigonal extravesical approach was utilized, depending on the length of the ureter. In all cases, a psoas hitch was performed to gain a longer submucosal tunnel and relieve tension, thus facilitating an efficient antireflux mechanism. RESULTS: Seventeen patients underwent a laparoscopic ureteral reimplantation after failed open surgery. Median age at second surgery was 106 months (interquartile range [IQR]: 53-122.5). Ipsilateral ureteral reimplantation with a combined intravesical and extravesical approaches was performed in 11 cases and cross-trigonal extravesical approach in 6 cases. Median ureteral diameter before the redo surgery was 16 mm (IQR: 14.5-18.5) and after surgery was 6 mm (IQR: 3.5-8.5) (p < 0.001). Postoperative mercaptoacetyltriglycine renal scan showed a nonobstructive pattern and stable renal function in all cases. CONCLUSION: Laparoscopic ureteral reimplantation with incorporation of a psoas hitch after failed open reimplantation is safe and effective.

The use of individualized 3D-printed models on trainee and patient education, and surgical planning for robotic partial nephrectomies.

3D printing is a growing tool in surgical education to visualize and teach complex procedures. Previous studies demonstrating the usefulness of 3D models as teaching tools for partial nephrectomy used highly detailed models costing between $250 and 1000. We aimed to create thorough, inexpensive 3D models to accelerate learning for trainees and increase health literacy in patients. Patient-specific, cost-effective ($30-50) 3D models of the affected urologic structures were created using pre-operative imaging of 40 patients undergoing partial nephrectomy at Thomas Jefferson University Hospital (TJUH) between July 2020 and May 2021. Patients undergoing surgery filled out a survey before and after seeing the model to assess patient understanding of their kidney, pathophysiology, surgical procedure, and risks of surgery. Three urological residents, one fellow, and six attendings filled out separate surveys to assess their surgical plan and confidence before and after seeing the model. In a third survey, they ranked how much the model helped their comprehension and confidence during surgery. Patient understanding of all four subjects significantly improved after seeing the 3D model (P < 0.001). The urology residents (P < 0.001) and fellow (P < 0.001) reported significantly increased self-confidence after interacting with the model. Attending surgeon confidence increased significantly after seeing the 3D model (P < 0.01) as well. Cost-effective 3D models are effective learning tools and assist with the evaluation of patients presenting with renal masses, and increase patient, resident, and fellow understanding in partial nephrectomies. Further research should continue to explore the utility of inexpensive models in other urologic procedures.

Does antithrombotic use enable earlier diagnosis of bladder cancer? A brief institutional assessment.

INTRODUCTION: Wallis et al (JAMA 2017) demonstrated use of antithrombotic medications (ATMs) is associated with increased prevalence of hematuria-related complications and subsequent bladder cancer diagnosis within 6 months. Stage of diagnosis was lacking in this highly publicized study. This study examined the association of ATM use on bladder cancer stage at the time of diagnosis. MATERIALS AND METHODS: We completed a retrospective chart review of patients with a bladder cancer diagnosis at our institution. Patient demographics and bladder cancer work up information were assessed. Patients were stratified based on use of ATMs at time diagnosis. Descriptive statistics were completed to identify association between ATM use and stage of bladder cancer diagnosis, as stratified by non-muscle invasive bladder cancer (NMIBC) versus muscle invasive bladder cancer (MIBC). RESULTS: A total of 1052 patient charts were reviewed. Eight hundred and forty-four were included and 208 excluded due to unavailability of diagnosis history. At diagnosis, 357 (42.3%) patients were taking ATMs. Patients on ATMs presented with NMIBC at similar rates as patients not taking ATMs (81.2% vs. 77.8%, p = 0.23). Subgroup analysis by ATM class similarly demonstrated no statistically significant differences in staging. CONCLUSION: While Wallis et al established that patients on blood thinners who present with hematuria are more likely to be diagnosed with genitourinary pathology, this factor does not appear to enable an earlier diagnosis of bladder cancer. Future study may assess hematuria at presentation (gross, microscopic), type of blood thinners, and low versus high risk NMIBC presentation.

Standardized single-stage laparoscopic Fowler-Stephens orchiopexy regardless of testis position: Modification of technique eliminates the need for intra-operative decision-making.

Background / Purpose: It is generally perceived that a primary laparoscopic orchiopexy has superior outcomes due to preservation of the testicular artery, and thus should be the choice when achievable. The two-stage laparoscopic Fowler-Stephens orchiopexy (LFSO) is considered superior regarding success rate compared to the one-stage procedure when the artery must be transected. Outcomes can be jeopardized when a primary orchiopexy is ultimately realized to be the incorrect procedure due to insufficient testicular artery length. It is preferable to decide the approach before initiating dissection, however, in reality, this does not always occur. A single uniform approach to all intraabdominal testes (IAT) that takes into consideration the main challenges encountered when performing laparoscopic orchiopexy can simplify the approach and potentially achieve good outcomes. We present our experience with a standardized approach for IAT regardless of testicular position and describe the surgical modification needed to achieve good results with the one-stage LFSO. Materials and Methods: Key surgical maneuvers implicated in the modified one-stage LFSO (M-LFSO) include preservation of a wide peritoneal flap between the vessels and the vas deferens, dissecting the vessels as proximal as possible and avoiding manipulation of the epididymis and vessels between the vas and epididymis when transferring the testis to the scrotum. Results: Our cohort included 55 boys (59 testes). Median age and weight at surgery were 13.3 months (interquartile range [IQR] 9.2-32.4) and 10.4 kg (IQR 9.2-12.6). The mean operative time was 70 min (IQR 60-85). The median follow-up was 11 months (IQR 7-12). There was one case of testicular atrophy (2%) and two cases of suboptimal testicular position in the scrotum at 6 months. Conclusions: M-LFSO is a standardized approach for all cases of IAT regardless of testicular position. Preservation of a wide peritoneal flap and proximal dissection of the vessels may contribute to the adequate testicular blood supply. The proposed approach eliminates the need for intra-operative decision-making and for ancillary procedures.

Pediatric Bladder Tumors: A Ten-Year Retrospective Analysis.

OBJECTIVE: To present our experience in a single pediatric urology practice over a 10-year period with bladder tumors in the pediatric population in an effort to add to the relatively small amount of existing data. We hope to expand the community's knowledge of presentations, management and natural history of pediatric bladder tumors. METHODS: We retrospectively queried our electronic medical records for International Classification of Diseases, Tenth Revision (ICD-10) and Current Procedural Terminology (CPT) codes relevant for bladder tumors. Patients with underlying bladder pathology, such as neurogenic bladder, history of bladder exstrophy, and history of bladder augmentation, were excluded. RESULTS: We identified 30 patients with bladder tumors from 2011 to 2021. There were 21 males and 9 females. Age at diagnosis ranged from 16 months to 19 years. Tumors identified were: 11 of various inflammatory subtypes; 4 papillomas; 4 rhabdomyosarcomas; 3 papillary urothelial neoplasms of low malignant potential and 8 of other types. Treatment included transurethral resection of bladder tumor, chemoradiation and laparoscopic partial cystectomy. Twenty nine patients had disease limited to the bladder and 1 had disease outside the bladder. Follow-up ranged from 2 weeks to 13 years (median 19 months). All patients had no evidence of disease at most recent follow-up. CONCLUSION: Pediatric bladder tumors range from aggressive rhabdomyosarcomas to more benign urothelial lesions. Fortunately, the latter type of tumor is the more prevalent lesion. Knowledge of the treatment options and natural history of these tumors will hopefully be of benefit to clinicians and parents alike.

Urethral Cancer After Urethroplasty: A Case Report and Review of the Literature.

OBJECTIVE: To review and report data on transformation to urethral carcinoma after urethroplasty for urethral stricture disease. Primary urethral carcinoma is a rare entity, and guidelines lack high quality data from which to cite. Urethroplasty is a highly effective treatment for urethral stricture disease, though in rare cases complications may include development of urethral carcinoma. METHODS: A systematic PubMed search was performed to identify all articles describing patients with urethral carcinoma after urethroplasty. Data were collected on the following parameters: patient age and sex, indication for urethroplasty, presentation of cancer, imaging, pathology, presence of metastasis, intervention, and outcome. RESULTS: The final cohort included fourteen patients, 13 from previously published cases and one from our institution. The median patient age at presentation was 60, most had endoscopic management prior to urethroplasty, and the majority presented with decreased urinary stream. All patients developed squamous cell carcinoma of the urethra. Patients underwent radical resection, lymph node dissection, chemotherapy, or radiotherapy, often in combination. A majority of patients had died at the time of case report. CONCLUSION: Development of urethral squamous cell carcinoma, particularly after urethroplasty, is a rarely encountered process. Patients and urologists must have a high index of suspicion and investigate symptoms such as fistula or lower urinary tract symptoms, even if these occur many months or even years after buccal mucosa graft . By compiling previously reported cases and adding an additional case to the literature, we hope that familiarity with this entity will lead to earlier recognition and diagnosis of disease.

Robot-assisted Modified One-Stage Orchiopexy: Description of a Surgical Technique.

BACKGROUND: In recent years, robot-assisted laparoscopic procedures have gradually replaced standard laparoscopic procedures in the realm of pediatric urology. The potential advantages of the robot-assisted technique include a higher degree of dexterity, three-dimensional visualization, and reproducibility. Although laparoscopic orchiopexy is considered to be the gold standard approach in cases of intra-abdominal testes, it can be technically challenging. A crucial point in decision-making is choosing between preservation of testicular blood vessels or sacrificing the vessels in order to achieve sufficient length, as with the one and two-stage Fowler-Stephens orchiopexy (FSO). It is perceived that the one-stage FSO has lower success rates than the two-stage procedure. We present a modification of the one-stage FSO procedure for intra-abdominal testes, utilizing a robot-assisted laparoscopic orchiopexy (RAL-O) method. METHODS: The key surgical maneuvers for the modified one-stage RAL-O include mobilization of the blood vessels and ligation of the artery as cranial as possible, maintenance of a wide flap of peritoneum between the vessels and vas deferens and employing the Prentiss maneuver. RESULTS: The cohort included 5 boys, all of which underwent RAL-O between April 2018 and May 2020. Median age at the time of surgery was 11 months (interquartile range [IQR] 8-16) and median weight was 9.6 kilograms (IQR 9.3-11.3). Median operating time and follow-up time were 97 minutes (IQR 77.5-109.5) and 8 months (IQR 4-14.5), respectively. All cases were completed as RAL-O and there was no conversion to a two-stage procedure. There were no cases of testicular atrophy. CONCLUSION: Modified one-stage Fowler Stephens RAL-O is safe and effective. It can be employed in all cases of intra-abdominal testis regardless of testis location, and eliminates the need for intra-operative decision-making, thus allowing for a standardized, one-stage approach.

Minimally Invasive Dismembered Extravesical Cross-Trigonal Ureteral Reimplantation for Obstructed Megaureter: A Multi-Institutional Study Comparing Robotic and Laparoscopic Approaches.

OBJECTIVE: To compare 2 minimally invasive surgical options for the treatment of obstructed megaureter: robot assisted dismembered extravesical cross-trigonal ureteral reimplantation (RADECUR) and laparoscopic dismembered extravesical cross-trigonal ureteral reimplantation (LDECUR). METHODS: A 2 arm retrospective comparative study, including all pediatric patients who underwent ureteral reimplantation of unilateral obstructed megaureter, either by RADECUR or LDECUR. Patient demographics, perioperative surgical data, complications, and results are described. The surgical technique in both arms was similar: dismembering of the ureter, performing an extravesical cross-trigonal detrusorotomy, and intracorporeal tailoring of the ureter when indicated, were the pivotal maneuvers utilized. RESULTS: The study included 95 patients (48 and 47 in the RADECUR and LDECUR arms, respectively) operated between the years 2016 and 2019. Overall, median age at surgery was 24 months (IQR 12-48) and median weight was 14 kg (IQR 11-21). Median operative time was 93 minutes (IQR 90-120) for RADECUR and 130 minutes (IQR 105-160) for LDECUR (P< 0.001). Intracorporeal excisional tapering was performed in 11 of the RADECUR patients and 19 LDECUR patients. Grade 1-2 Clavien-Dindo complications occurred in 7 patients, and grade 3 complication in 1 patient in the RADECUR arm. In the LDECUR arm, grade 1-2 complications occurred in 2 patients, and 2 had a grade 3 complications. Surgical success was achieved in 97% and 94% in the RADECUR and LDECUR groups, respectively. CONCLUSION: Unilateral robotic extravesical cross-trigonal ureteral re-implantation for treatment of obstructed megaureter in the pediatric population is safe and effective both for RADECUR and LDECUR. Operative time is significantly shorter for RADECUR.

Ureteral Triplication- Laparoscopic Partial Nephrectomy With Highly Selective Arterial Dissection: Description of Surgical Technique.

BACKGROUND/OBJECTIVE: Ureteral triplication is a rare congenital malformation with a wide spectrum of presentation that requires a high index of suspicion in order to diagnose. To date, only about 100 cases have been published in medical literature. Smith et al1 proposed a classification for ureteral triplication that describes it as three separate ureters and three separate ureteral orifices with no interconnection between ureters. In this video, we present a surgical approach for laparoscopic partial nephrectomy of both upper moieties in the context of ureteral triplication. MATERIALS AND METHODS: The procedure is initiated with cystoscopy and retrograde pyelogram to better determine the pertinent anatomy. A ureteral catheter is inserted into the healthy ureter to facilitate its identification and reduce the risk of inadvertent injury. The patient is placed in the modified flank position. A 5 mm camera port is inserted using the Hasson technique and two additional ports are inserted under vision. The colon is deflected medially, and the kidney, ureters and blood supply are identified. Both upper pole ureters are transected. Variance of the blood supply can be encountered; therefore, highly selective dissection of the vessels is performed, and care is taken to preserve the main renal vessels. Upper pole partial nephrectomy is carried out using a harmonic scalpel at the demarcation line. RESULTS: Operative time was 182 minutes. Discharge was on post-operative day 2 without intra or postoperative complications. Follow-up ultrasound 3 months postoperation demonstrated a normal lower pole moiety without hydronephrosis or hydroureter. CONCLUSIONS: Laparoscopic partial nephrectomy with highly selective dissection of vessels in the context of a ureteral triplication anomaly is feasible and safe. Abnormal blood supply should be considered and addressed accordingly.

Robot-assisted Laparoscopic Extravesical Cross-trigonal Ureteral Reimplantation With Tailoring for Primary Obstructive Megaureter.

OBJECTIVE: To describe a novel, minimally invasive surgical technique, robotic-assisted laparoscopic dismembered extravesical cross-trigonal ureteral reimplantation for primary obstructive megaureter and to report a case series of 13 patients. METHODS: Thirteen patients between the ages of 10 and 96 months who were diagnosed with primary obstructive megaureter underwent robotic-assisted laparoscopic dismembered extravesical cross-trigonal ureteral reimplantation between April 2017 and May 2019. The principle of this technique is performing an extravesical cross-trigonal ureteral reimplantation with intracorporeal tailoring of the ureter. This provides the advantage of achieving a long tunnel mimicking the Cohen cross-trigonal ureteral reimplantation, without performing the open surgical technique and offers the potential benefits of minimally invasive surgery. Surgical technique is described, demographic data and intra- and/or postoperative parameters are reported. RESULTS: Median age was 26 months (IQR 16-60). Median weight was 15 kg (IQR 10.1-31). Median console time was 113 minutes (IQR 90.5-140). Median postoperative stay was 2.5 days (IQR 1.3-3). Median ureteral diameter decreased from 17 mm (IQR 12.5-18.5) to 3 mm (IQR 0-6.5, P = .001). Median renal pelvis diameter decreased from 28 mm (IQR 20.5-37.8) to 4 mm (IQR 1.5-5, P = .005). Median renal function before surgery was 46% (IQR 24.5-48.5) and following surgery was 42% (IQR 36-42, P = .700). Median T1/2 decreased from 28 minutes (IQR 19.3-30) to 4.5 minutes (IQR 3-5, P = .009). Postoperative complications graded by the Clavien-Dindo classification were apparent in 3 patients (21%). One had grade I complication (fever, resolved spontaneously) and 2 had a Grade II complication (urinary tract infection). CONCLUSION: Robot-assisted cross-trigonal ureteral reimplantation with intracorporeal tailoring is safe, feasible, and reproducible in short-term follow-up.

Robot-assisted Laparoscopic Pyeloplasty for "Huge" Hydronephrosis Causing Vena Cava Thrombus.

OBJECTIVE: To present a rare case of "huge" hydronephrosis causing distortion of large vessels and formation of a thrombus in the inferior vena cava. Multidisciplinary treatment was applied with particular focus on pyeloplasty utilizing a robot-assisted laparoscopic approach. METHODS: A 20-month-old male presented to the emergency room severely ill with abdominal pain, nausea, vomiting, and fever and was subsequently transferred to the intensive care unit, in septic shock. An abdominal ultrasound revealed a large multilobular cystic structure in the right hemiabdomen, which was initially interpreted as an infected mesenteric cyst. CT scan revealed a huge hydronephrotic kidney crossing the midline, causing a mass effect that compressed and distorted the vena cava laterally, in addition to a thrombus between the hepatic vein and right renal vein. Intravenous Ceftriaxone and Amikacin, as well as anticoagulation therapy with low molecular weight heparin (Enoxaparin) were initiated. A nephrostomy tube was inserted that drained 900 mL of purulent urine. A full hematology investigation including protein C, S, and antithrombin III was carried out, excluding factor V Leiden and prothrombin mutation. All values were in the normal range. Dimercaptosuccinic Acid (DMSA) scan showed 30% function on the affected kidney and Voiding Cystourethrogram (VCUG) excluded any bladder pathology or reflux. Subcutaneous Enoxaparin was continued for 3 months, maintaining antifactor Xa in the therapeutic range (0.7-1 IU/mL). Ultrasound Doppler of the vena cava showed full resolution of the thrombus. Robot-assisted laparoscopic pyeloplasty was performed and significant reduction of the renal pelvis was carried out, taking care to preserve the calyces. Postoperative ultrasound 4 months after surgery showed a complete resolution of the hydronephrosis. CONCLUSION: Giant hydronephrosis is a rare finding. Distortion of adjacent veins and formation of thrombosis should be kept in mind, as they are life threatening. A multidisciplinary collaboration is mandatory to ensure optimal treatment.

Engineered Interspecies Amino Acid Cross-Feeding Increases Population Evenness in a Synthetic Bacterial Consortium.

In nature, microbes interact antagonistically, neutrally, or beneficially. To shed light on the effects of positive interactions in microbial consortia, we introduced metabolic dependencies and metabolite overproduction into four bacterial species. While antagonistic interactions govern the wild-type consortium behavior, the genetic modifications alleviated antagonistic interactions and resulted in beneficial interactions. Engineered cross-feeding increased population evenness, a component of ecological diversity, in different environments, including in a more complex gnotobiotic mouse gut environment. Our findings suggest that metabolite cross-feeding could be used as a tool for intentionally shaping microbial consortia in complex environments.IMPORTANCE Microbial communities are ubiquitous in nature. Bacterial consortia live in and on our body and in our environment, and more recently, biotechnology is applying microbial consortia for bioproduction. As part of our body, bacterial consortia influence us in health and disease. Microbial consortium function is determined by its composition, which in turn is driven by the interactions between species. Further understanding of microbial interactions will help us in deciphering how consortia function in complex environments and may enable us to modify microbial consortia for health and environmental benefits.

Identification of a Fifth Antibacterial Toxin Produced by a Single Bacteroides fragilis Strain.

Bacteroidales are the most abundant Gram-negative bacteria of the healthy human colonic microbiota, comprising nearly 50% of the colonic bacteria in many individuals. Numerous species and strains of gut Bacteroidales are present simultaneously at high concentrations in this ecosystem. Studies are revealing that gut Bacteroides has numerous antibacterial weapons to antagonize closely related members. In this study, we identify a new diffusible antibacterial toxin produced by Bacteroides fragilis 638R, designated BSAP-4. This is the fifth antibacterial toxin produced by this strain and the second toxin of this strain with a membrane attack complex/perforin domain (MACPF). We identify the target molecule of sensitive cells as a ß-barrel outer membrane protein (OMP) with calycin-like domains. As with other MACPF toxins, the gene encoding the target in sensitive strains is in the same genetic region as bsap-4 in producing strains. A comparison of B. fragilis strains showed there are two sensitive variants of this OMP that are 87% similar to each other and 50% similar to the resistant OMP. Unlike other MACPF toxins, there are numerous B. fragilis strains that harbor the resistant OMP without bsap-4 Several OMP variants from strains that are BSAP-4 resistant under the conditions of our assay confer BSAP-4 sensitivity to Bacteroides thetaiotaomicron when constitutively expressed. Using a reporter assay, we show that the BSAP-4 receptor gene is differentially expressed in sensitive and resistant strains leading to apparent BSAP-4 resistance under the conditions of our assay, despite harboring the BSAP-4 target gene.IMPORTANCE The intestinal microbiota is a diverse microbial ecosystem that provides numerous benefits to humans. The factors that govern its establishment and stability are just beginning to be elucidated. Identification and characterization of antimicrobial toxins produced by its members and their killing range are essential to understanding the role of antagonism in community composition and stability. Here, we identify a fifth antimicrobial toxin produced by a single Bacteroides fragilis strain and identify its target. The finding of such a large number of toxins that antagonize competing members suggests that this feature substantially contributes to the fitness of these bacteria. In addition, these toxins may have applications in genetically engineered gut bacteria to allow engraftment or to antagonize a potentially pathogenic member.