Sumit Dave

The microbiome of the urinary tract—a role beyond infection

Urologists rarely need to consider bacteria beyond their role in infectious disease. However, emerging evidence shows that the microorganisms inhabiting many sites of the body, including the urinary tract—which has long been assumed sterile in healthy individuals—might have a role in maintaining urinary health. Studies of the urinary microbiota have identified remarkable differences between healthy populations and those with urologic diseases. Microorganisms at sites distal to the kidney, bladder and urethra are likely to have a profound effect on urologic health, both positive and negative, owing to their metabolic output and other contributions. Connections between the gut microbiota and renal stone formation have already been discovered. In addition, bacteria are also used in the prevention of bladder cancer recurrence. In the future, urologists will need to consider possible influences of the microbiome in diagnosis and treatment of certain urological conditions. New insights might provide an opportunity to predict the risk of developing certain urological diseases and could enable the development of innovative therapeutic strategies.

Prevention of chronic kidney disease in spina bifida

ObjectiveThe prevalence of progressive chronic kidney disease (CKD) in children and adults with spina bifida is considerable, rising, and entirely preventable.Removing the cause: prevention of spina bifidaThe best prevention of CKD in spina bifida is prevention of spina bifida itself through strategies that include folate supplementation, ideally before pregnancy.The cause of CKDDysfunctional bladder outlet causes febrile Urinary Tract Infections (UTI), even with clean intermittent catheterization (CIC), and subsequent renal scarring. The development of secondary vesicoureteric reflux (VUR) increases the risk of renal scarring and CKD.Finding the ideal marker for measurement of renal function in spina bifidaCreatinine-based methods are insensitive because of low muscle mass and underdeveloped musculature in the legs. Only Cystatin C–based eGFR can reliably assess global renal function in these patients. However, unilateral renal damage requires nuclear medicine scans, such as 99mTc DMSA.(Video)Urodynamics studies (UDS)Early treatment is recommended based on UDS with anticholinergics, CIC, and antibiotic prophylaxis when indicated. Overnight catheter drainage, Botox, and eventually augmentation cystoplasty are required for poorly compliant bladders. A continent child or one rendered continent following surgery is at a higher risk of renal damage.ConclusionA multidisciplinary approach is required to reduce the burden of CKD in patients with spina bifida. The right tools have to be utilized to monitor these patients, particularly if recurrent UTIs occur. Cystatin C eGFR is preferred for monitoring renal damage in these patients, and 99mTc DMSA scans have to be used to detect unilateral renal scarring.

Learning From the Learning Curve: Factors Associated With Successful Endoscopic Correction of Vesicoureteral Reflux Using Dextranomer/Hyaluronic Acid Copolymer

PURPOSE Conflicting reports exist regarding the parameters guiding successful correction of vesicoureteral reflux using dextranomer/hyaluronic acid copolymer. We performed logistic regression analysis to evaluate the effect of injected volume while adjusting for other factors potentially associated with success following dextranomer/hyaluronic acid copolymer injection. MATERIALS AND METHODS Between July 2003 and June 2006, 126 consecutive patients (34 boys and 92 girls) with a mean +/- SD age of 6.5 +/- 3.7 years with primary vesicoureteral reflux (196 refluxing ureters) underwent injection for febrile urinary tract infections. Success was defined as complete reflux resolution. Age, gender, laterality, preoperative vesicoureteral reflux grade, surgeon experience, dextranomer/hyaluronic acid copolymer volume, time to surgery from initial presentation and preoperative treatment for lower urinary tract symptoms were analyzed. RESULTS Vesicoureteral reflux grade was I to V in 7 (3.5%), 53 (27%), 91 (46.4%), 30 (15.3%) and 15 renal units (7.6%), respectively. The success rate after 1 injection was 50% by patient and 59.2% by ureter. Mean injected volume was 0.9 +/- 0.27 ml in those who had a successful injection vs 0.67 +/- 0.24 ml in those in whom injection failed (p <0.001). The success rate after 1 injection was 78.9% using 0.8 ml or greater dextranomer/hyaluronic acid copolymer compared to 31.7% with less than 0.8 ml. Multivariate analysis confirmed that higher dextranomer/hyaluronic acid copolymer volume (p = 0.001), lower preoperative grade (p = 0.013), surgeon experience (p = 0.025) and treatment for lower urinary tract symptoms (p = 0.009) were associated with successful correction of vesicoureteral reflux. CONCLUSIONS Our analysis strengthens the previously reported association of surgeon experience and vesicoureteral reflux grade with successful endoscopic vesicoureteral reflux correction. The data also revealed an association between injected volume and vesicoureteral reflux correction even while controlling for other variables, highlighting its importance as a true success modifier.

Ventral Penile Lengthening Versus Dorsal Plication for Severe Ventral Curvature in Children With Proximal Hypospadias

PURPOSE The 2 main approaches to correct severe ventral curvature are dorsal plication of the corpora and ventral corporeal lengthening by tunica albuginea patching. Controversy persists since neither technique has been proved to be superior to the other with respect to initial or long-term outcome. However, to our knowledge a direct comparison of outcome of these 2 procedures has not been previously reported. MATERIALS AND METHODS A retrospective review of the records of 100 consecutive patients who underwent repair of penoscrotal or more proximal defects from 1996 to 2004 was performed. Children were divided into 2 groups, including group 1-32 who underwent a ventral penile lengthening procedure and group 2-68 who underwent dorsal plication. Meatal location, preoperative testosterone stimulation, severe ventral curvature (greater than 45 degrees) at the beginning of operation and after degloving, proximal ventral dissection, urethral plate transection and recurrent ventral curvature were compared between the 2 groups. RESULTS Mean age was 17 months (range 9 to 56) in patients with ventral penile lengthening and 17.8 months (range 10 to 58) in patients with dorsal plication. Mean followup was 65 (range 29 to 120) and 62 months (range 30 to 116), respectively. Of the 32 group 1 children 30 (93.7%) had penoscrotal or more proximal hypospadias vs 57 of the 68 (83.8%) in group 2. Three of the 32 children who underwent ventral penile lengthening had recurrent ventral curvature vs 19 of the 68 who underwent dorsal plication (9.4% vs 27.9%, p = 0.03). On multivariate analysis dorsal plication remained significantly associated with recurrent ventral curvature independently of the other factors (OR 4.56, 95% CI 1.14-18.28, p = 0.03). CONCLUSIONS Dorsal plication was more often associated with recurrent ventral curvature compared to ventral penile lengthening on univariate and multivariate analysis. Future studies adjusting for proximal ventral dissection and urethral plate transection are necessary to further elucidate the role of each technique in the correction of severe ventral curvature in children with proximal hypospadias.

Is Long-Term Bladder Deterioration Inevitable Following Successful Isolated Bladder Outlet Procedures in Children With Neuropathic Bladder Dysfunction?

PURPOSE Bladder decompensation is well described following artificial urinary sphincter implantation in neurogenic bladders. We evaluated the long-term results of various bladder outlet procedures in a subset of patients with neurogenic bladder and isolated outlet deficiency. MATERIALS AND METHODS We retrospectively reviewed the charts of 15 consecutive patients who underwent bladder outlet procedures during a 10-year period for urinary incontinence associated with neuropathic bladder dysfunction. Postoperative success was defined as a dry interval of at least 4 hours. RESULTS Preoperative evaluation showed a smooth bladder in 11 patients with vesicoureteral reflux and hydronephrosis in 2. Using the minimal acceptable capacity for age, mean percent expected bladder capacity for age was 89% +/- 25%, capacity below 20 cm H(2)O was 81% and capacity below 30 cm H(2)O was 89%. Mean preoperative expected capacity for age was 60% +/- 18%. Mean postoperative followup was 11.2 years. Postoperatively, 11 patients achieved initial dryness but 9 subsequently presented with recurrent incontinence and 2 presented with upper tract deterioration. Four cases failed the initial bladder outlet procedure. Salvage procedures included augmentation cystoplasty in all 15 patients, combined with repeat bladder outlet procedure in 4 and bladder neck closure in 2. Mean time to augmentation cystoplasty was 39.6 +/- 28 months. CONCLUSIONS Isolated bladder outlet procedures for neurogenic incontinence portend a poor long-term outcome, requiring augmentation cystoplasty despite the use of anticholinergic medications and strict followup. Preoperative urodynamic evaluation does not predict the need or timing from the initial bladder outlet procedure for future augmentation cystoplasty.

Potential Complications With the Prescrotal Approach for the Palpable Undescended Testis? A Comparison of Single Prescrotal Incision to the Traditional Inguinal Approach

PURPOSE Prescrotal orchiopexy is emerging as an alternative surgical approach to undescended testicles. We compare operative times, success rates and complications of single incision prescrotal orchiopexy and the traditional inguinal approach. MATERIALS AND METHODS During a 3-year period all patients who underwent prescrotal orchiopexy were retrospectively reviewed and compared to age matched controls operated on via the traditional inguinal approach. Data collected included preoperative and postoperative testicular positioning, operative time and complications, including testicular atrophy and ascent. Exclusion criteria were retractile or ectopic testis, incomplete data, including lack of followup, and a concurrent procedure at the time of orchiopexy. RESULTS A total of 63 orchiopexies were performed using the prescrotal approach (mean patient age 4.6 years) and the inguinal approach (4.7 years). Average surgical times for the prescrotal and inguinal groups were 34 and 64 minutes, respectively (p = 0.002). Followup ranged from 6 to 42 months. Complication rates between the groups were similar. However, 2 hernias (3%) occurred in the prescrotal group, of which 1 was incarcerated and associated with Meckels diverticulum, and 1 was a late recurrence. CONCLUSIONS With the paucity of literature on prescrotal orchiopexy potential complications may be underreported. Despite the limitations of sample size, prescrotal orchiopexy may be associated with a 3% risk of postoperative hernia. A single incision prescrotal orchiopexy is still a viable approach for patients with primary palpable undescended testicles. Advantages include shorter operative time, a cosmetically appealing single incision and possibly less pain.

Single-Institutional Study on Role of Ureteroscopy and Retrograde Intrarenal Surgery in Treatment of Pediatric Renal Calculi

OBJECTIVES Ureteroscopy (URS) is accepted as a primary modality to treat ureteral calculi in children and extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy continue to be the primary option for renal stones. We report our experience with the use of URS in managing pediatric upper tract calculi and evaluate the results in relation to stone location, size, and the use of URS as a primary or secondary treatment modality. METHODS A retrospective chart review was performed for all children who underwent URS for renal stones from 1999 to 2004. Success was defined as complete radiologic clearance. RESULTS A total of 19 patients (mean age 6.9 years) with 23 calculi underwent URS and were followed up for a mean of 23 months. The stones were located in the renal pelvis in 8 patients, and the polar regions in 4 and 7 patients had partial staghorn calculi with >1 caliceal extension. The primary and secondary success rate for patients with renal calculi was 80% (5 of 8) and 66% (2 of 3) for pelvic stones and 100% (4 of 4) for polar stones. Only 1 of the partial staghorn calculi was completely cleared with URS. Complications included distal ureteral perforation in 1 and urinoma in 1. CONCLUSIONS URS achieves reasonable results with minimal complications in pediatric patients with renal pelvic calculi. Polar stones required multiple sessions for complete clearance, and staghorn calculi were not amenable to URS. Additional studies are necessary to define the role of URS as an option in the surgical treatment of children with renal calculi.

Current status of bladder neck reconstruction.

Purpose of review This paper reviews the literature over the last 3 years on bladder outlet procedures for children with urinary incontinence. The multitude of procedures and need for concomitant bladder augmentation indicates that there is no ideal surgical option for these children. Recent findings The results of bladder neck slings with or without bladder augmentation have been reported in some key studies during this review period. Several modifications of the bladder wrap around sling and modifications of the Kropp–Salle procedure are described. Long-term results of bladder neck injections are highlighted. Preliminary results of complete primary repair of bladder exstrophy are compared with those of staged repair. Summary Achieving urinary continence is difficult and continues to challenge the reconstructive surgeon. Standardized definition of dryness and further efforts to search for preoperative criteria to define the etiology of incontinence are needed to better assess outcomes.

Risk Factors for Perinephric Hematoma Formation After Shockwave Lithotripsy: A Matched Case-Control Analysis

PURPOSE To determine the incidence of and evaluate the potential risk of a symptomatic perinephric hematoma (PNH) after shockwave lithotripsy (SWL) with the Storz Modulith SLX-F2 device. PATIENTS AND METHODS Patient and treatment-related data from 6172 SWL treatments for proximal ureteral and kidney stones were collected prospectively from April 2006 to August 2010. Patients in whom signs or symptoms of a PNH developed after SWL were investigated with imaging studies. Each patient identified with a PNH was matched with four controls using sex, age (±5 years), shockwave rate, energy and number, and no SWL within the previous 6 months as the matching variables. The baseline characteristics of the 21 cases and 84 controls were compared using the Student t test. The independent variables of hypertension (intraoperative value >140/90 mm Hg), anticoagulant/antiplatelet drugs, obesity (body mass index ≥30), and diabetes were compared using a conditional logistic regression analysis. The dependent variable was hematoma. RESULTS A PNH developed after SWL with the Storz Modulith SLX-F2 device in 21 (0.34%) adult patients (19 men, 2 women) with a mean age of 55.2 years. Significant risk factors identified included intraoperative hypertension (hazard ratio [HR] 3.302, 1.066-10.230, P=0.0384) and anticoagulant/antiplatelet medications (HR 4.198, 1.103-15.984, P=0.0355). Diabetes (P=0.1043) and obesity (P=0.1021) were not associated with PNH. CONCLUSIONS A clinical PNH occurred in less than 1% of our population. This is consistent with reports from earlier generation devices. Risk factors identified for hematoma formation were intraoperative hypertension and the use of anticoagulant/antiplatelet drugs.

Open Versus Laparoscopic Staged Fowler-Stephens Orchiopexy: Impact of Long Loop Vas

PURPOSE There is a paucity of literature on factors associated with testicular atrophy following second stage laparoscopic Fowler-Stephens orchiopexy. We hypothesized that dissection of a long looping vas during this procedure could compromise testicular blood supply, leading to testicular atrophy. MATERIALS AND METHODS Following an initial laparoscopic testicular vessel ligation, a second stage Fowler-Stephens orchiopexy was performed in 73 testes (laparoscopic in 61, open in 12). The presence of a long looping vas was noted from the first stage operative notes. Doppler ultrasound was performed postoperatively to confirm testicular atrophy. RESULTS Atrophy rate at a mean followup of 13.5 months was 20.5% (15 of 61 in laparoscopic and 0 of 12 in open orchiopexy). None of the 5 long looping vas testes atrophied following open orchiopexy, compared to 5 of 6 (83%) following laparoscopic orchiopexy (p = 0.03). Analyzing the laparoscopic group alone, a long looping vas was significantly associated with risk of atrophy (p <0.01). CONCLUSIONS The presence of a long looping vas was associated with a higher atrophy rate following laparoscopic second stage Fowler-Stephens orchiopexy. Laparoscopic management of the long looping vas may be more challenging and, therefore, in such cases open Fowler-Stephens orchiopexy may result in better success rates by preserving the integrity of the collateral vessels.