Liam McCarthy

Endoscopic placement of double-J ureteric stents in children as a treatment for primary obstructive megaureter

Aim: To determine the efficacy and potential complications of double-J ureteric stents in the treatment of persistent or progressive primary obstructive megaureter in pediatric patients within our institution. Materials and Methods: A retrospective case-note review of all patients with double-J ureteric stents, between 1997 and 2004, was performed. In all, 38 stents were inserted in 31 patients aged between 2 months and 15 years of age. Complications and results of follow-up investigations and the need for follow-up investigations were recorded. Patients were followed up clinically and radiologically for a minimum of 2 years following stent insertion. Results: Endoscopic placement of double-J ureteric stents in childhood is straightforward and complications are uncommon (8/38 insertions). In non-resolving or progressive primary non-refluxing megaureter, double-J ureteric stenting alone is effective with resolution of primary non-refluxing megaureter in 66% of cases (25/38 insertions). Conclusions: Ureteric stenting provides an alternative to early surgery in patients with primary non-refluxing megaureter. The youngest patient in our series was 2 months old at the time of endoscopic ureteric double-J stent insertion. Endoscopic placement of ureteric double-J stents should be considered as a first-line treatment in the management of persistent or progressive non-refluxing megaureter leading to progressive hydronephrosis or pyonephrosis.

Urinomas protect renal function in posterior urethral valves—a population based study

BACKGROUND/PURPOSE Urinomas have been thought to protect renal function in boys with posterior urethral valves (PUVs), although recent reports have disputed this. This study tested the hypothesis that urinomas protect global renal function in boys with PUV. METHODS A retrospective analysis of all boys with PUV presenting to a tertiary unit derived from a region with an estimated population of 5.5 million was performed. Comparisons of the initial nadir creatinine, current creatinine, and renal status score (RSS) were made between those with and without urinomas. The RSS was derived from nephrology assessment of current renal status (0 = normal to 4 = end-stage renal failure or transplantation). Results were given as median (range), except for RSS, which was given as mean +/- SEM. P < or = .05 was regarded as significant. RESULTS During 1989-2009, 9 of 89 PUV boys were diagnosed with urinomas. Initial nadir creatinine was statistically lower in boys with urinomas (31 [18-44] vs 45 [20-574] mumol/L, P < .01). Length of follow-up was similar (5.1 [2.2-17.3] vs 5.9 [1.8-19.7] years, P = .59). Follow-up creatinine was significantly lower in urinoma boys (44 [25-77] vs 61 [29-1227] micromol/L, P < .05), as was the RSS (0.14 +/- 0.14 vs 0.91 +/- 0.14, P < .01). No urinoma boys progressed to end-stage renal failure or required transplant. CONCLUSION This population-based study of PUV boys demonstrates that urinomas reduce nadir creatinine and significantly protect long-term global renal function.

What is the efficacy of circumcision in boys with complex urinary tract abnormalities

The risk of urinary tract infection (UTI) in normal boys is 1%. This risk is significantly increased in boys with congenital abnormalities of the urinary tract, which includes such abnormalities as vesico-ureteric reflux, obstructive megaureter (VUJO) and posterior urethral valves. UTI in these boys can lead to urosepsis, a potentially life-threatening complication, and in the longer term renal scarring complicating pyelonephritis can lead to chronic renal impairment or even end-stage renal disease. Circumcision has been shown in normal boys to reduce the risk of UTI by 90%, and potentially could be a simple intervention to reduce the risk of urosepsis and renal scarring. In order to make this decision a clinician really needs to have the answers to two questions: 1) What is the risk of UTI in this particular boy? 2) What is the evidence of efficacy of circumcision in this particular condition? This article reviews what evidence exists to make a calculation of the risk/benefit ratio for circumcision in boys with abnormalities of the urinary tract.

Introduction of sodium pentosan polysulfate and avoidance of urethral catheterisation: improved outcomes in children with haemorrhagic cystitis post stem cell transplant/chemotherapy

PURPOSE Haemorrhagic cystitis (HC) is an uncommon but potentially devastating complication of chemotherapy and bone marrow transplantation in children. We aimed to test the hypothesis that early recognition, sodium pentosan polysulfate (SPP), and avoidance of urethral catheterisation improve outcomes in children with HC. METHODS A retrospective case note review was performed of all patients treated for HC in our hospital from 2002 to 2010. A protocol for the management of HC was introduced in 2007 advocating early detection, use of SPP, and avoidance of urethral catheterisation. Data collected on each patient included primary condition, medications at onset, blood transfusions, duration of symptoms, catheter usage, and outcome. Statistical analysis was performed using the Mann-Whitney U test, and Fishers Exact test as appropriate, P < .05 being significant. RESULTS Five patients were treated using protocol with 5 historical controls. There was no significant difference between the ages of the group, diagnosis, and treatment at onset of HC. In the historical group, 4 of 5 died with HC, but all recovered in the protocol group (P < .05). Blood transfusion requirements were also significantly reduced after protocol introduction (P < .05). CONCLUSION Early identification, avoidance of urethral catheterisation, and use of SPP significantly reduces blood transfusion requirements and mortality from HC.

Extended spectrum beta lactamase (ESBL) producing bacteria urinary tract infections and complex pediatric urology

AIM OF THE STUDY Extended spectrum beta lactamase (ESBL) producing bacteria are resistant to most beta-lactam antibiotics including third-generation cephalosporins, quinolones and aminoglycosides. This resistance is plasmid-borne and can spread between species. Management of ESBL is challenging in children with recurrent urinary tract infections (UTIs) and complex urological abnormalities. We aim to quantify the risk in children and specifically in urological patients. METHODS Retrospective review of a microbiology database (April 2014 to November 2015). This identified urine isolates, pyuria, ESBL growth and patient demographics. Data analysis was by Chi square, Mann-Whitney U-test and ANOVA. A P value of <0.05 was taken as significant. MAIN RESULTS Analysis of 9418 urine samples showed 2619 with pure isolates, of which 1577 had pyuria (>10×106 WC/L). 136 urine cultures (n=79 patients) grew purely ESBL. Overall, 5.2% of urine isolates were ESBL and 9.5% isolates with pyuria (>100×106 WC/L) had ESBL, whereas only 22/1032 (2.1%) with no pyuria, (P<0.0001). Urology patients had 86/136 (63%) ESBL positive cultures. These represented 86/315 (27%) of all positive cultures for urology patients vs. 50/2267 (2.2%) for all other specialties (P<0.0001). Potential ESBL transmission between organisms occurred in 3 (all on prophylactic antibiotics). Over the study period, there was no significant rise of the monthly incidence between 2014 and 2015 (ANOVA P=0.1). CONCLUSION This study is the first to document the incidence of ESBL in children (5%), and estimate the frequency of possible plasmid transmission between bacterial species in children. This quantifies the risk of ESBL, especially to urology patients, and mandates better antibiotic stewardship. LEVEL OF EVIDENCE Level IIc.

Prediction of need for intervention in posterior urethral valves: Use of urine osmolality

AIM Renal tubular dysfunction (RTD) causing obligate production of hypoosmolar urine in boys with posterior urethral valves (PUVs) has been described. It is not known how clinically significant this is. We hypothesize that a feedback loop is present in many PUV boys who suffer deterioration of their lower urinary tract (LUT). RTD results in hypoosmolar urine, obligate polyuria, and bladder stretch-injury. The increasing back-pressure worsens RTD, thus exacerbating the injury. Coexisting renal dysplasia and acquired renal scarring exacerbate this. We compared the concentrating ability (random clinic urine osmolality) of PUV boys who had no LUT deterioration to those who required intervention, examining the confounding effect of renal impairment with a subgroup analysis comparing those with plasma creatinine ≤80μmol/l. METHODS A retrospective review of our PUV database was performed. Age, intervention, and highest recorded random clinic urine osmolality (>1year) with concurrent plasma creatinine were recorded (normal urine osmolality 500-850 mOsm/kg). Data are given as median values, analyzed by Mann-Whitney u-test, with P<0.05 deemed significant. MAIN RESULTS Urine osmolality was available in 77 boys with PUV out of 125 in our series. Of these, 34 required subsequent intervention (e.g., Mitrofanoff procedure, bladder augmentation). Age at testing trended towards being higher in the intervention group [7.9 (4.3-10.9) years vs. nonintervention 6.3 (4-8.4); P=0.06]. Urine osmolality was significantly reduced in the intervention group [411(293-547) vs. 631 (441-805) mOsm/kg; P<0.001]. Subgroup analysis comparing only those with creatinine ≤80μmol/l was respectively 451 (322-567) mOsm/kg (n=22) vs. 645 (469-810) mOsm/kg (n=40), P<0.01. CONCLUSION This study confirms that hypoosmolar urine is highly associated with progression of LUT dysfunction, requiring intervention. Even boys with normal creatinine values have a greater risk of LUT deterioration if they have a RTD and produce hypoosmolar urine. LEVEL OF EVIDENCE IV (retrospective service development project).