Development and content validation of the percutaneous nephrolithotomy assessment score.

OBJECTIVES: To develop and content validate a percutaneous nephrolithotomy assessment score, taking into consideration the procedure-specific risks. METHODS: This prospective international study utilized the Healthcare Failure Mode and Effect Analysis to systematically outline percutaneous nephrolithotomy and failure modes for each step. A total of 25 h was spent observing percutaneous nephrolithotomy carried out by six expert surgeons. Hazard analysis scoring was carried out by 11 experts. It was determined if the steps were single point weaknesses. Single point weaknesses and those assigned a hazard score ≥4 were included in the percutaneous nephrolithotomy assessment score. The tool was then content validated by 16 experts from 10 countries. RESULTS: Application of the Healthcare Failure Mode and Effect Analysis identified 64 failure modes; 37 failure modes had a hazard score ≥4. After adaptations based on expert feedback the final percutaneous nephrolithotomy assessment score was developed containing 10 phases, 21 processes and 47 subprocesses. All participants agreed that the tool contained pertinent procedural steps. CONCLUSIONS: This study has developed and shown the international content validity of a novel percutaneous nephrolithotomy assessment score. The tool can be utilized in modular operating room training to quantify operator progress, and can be used in conjunction with other modules as part of a complete percutaneous nephrolithotomy curriculum for trainees.

Investigating upper urinary tract urothelial carcinomas: a single-centre 10-year experience.

OBJECTIVES: Evidence of the accuracy of predictive tests in confirming the presence and grade of upper urinary tract urothelial carcinomas (UUTUC) is limited. We present the largest series evaluating the diagnostic value of pre- and intra-operative parameters in the detection of UUTUC. MATERIALS AND METHODS: We retrospectively analysed records of patients who underwent diagnostic ureteroscopy between 2005 and 2014 for suspected UUTUC. Pre-operative workup included voided urine cytology and CT imaging. Intra-operative assessments involved ureteroscopy to directly visualise suspicious lesions, and where possible selective cytology and biopsy. Primary outcomes were the visualisation of UUTUC and histopathological confirmation of tumour. RESULTS: Hundred out of 160 (63 %) patients presenting with suspected upper tract malignancy had UUTUC. Voided and selective urine cytology and CT individually predicted UUTUC with a sensitivity/specificity of 63/67, 76/73, and 95/26 %, respectively. Forty out of 48 (83 %) patients who had abnormal CT and abnormal voided urine cytology had UUTUC, while 100 % of those with normal CT and normal voided cytology (investigated for ongoing symptoms) were normal. Comparing endoscopic biopsy to nephroureterectomy specimen grade, 19 (46 %), 18 (44 %), and 4 (10 %) were identical, upgraded, and downgraded, respectively. CONCLUSION: Pre-operative investigations can predict UUTUCs. When these investigations were normal, the risk of UUTUC is negligible. In selective patients with abnormal investigations, ureteroscopy should be performed to confirm and predict the grade of UUTUC, in order to guide future management. Selective cytology is unlikely to significantly contribute to the diagnostic workup of UUTUC.

Extended-spectrum beta-lactamase-producing Enterobacteriaceae in hospital urinary tract infections: incidence and antibiotic susceptibility profile over 9 years.

PURPOSE: Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are an increasing concern regarding antibiotic resistance and their potential to cause serious infections which are difficult to treat. The purpose of this surveillance programme was to assess the incidence of ESBL in adults amongst urinary isolates, identify risk factors, and detail the antibiotic susceptibility profile in order to guide empirical treatment. METHODS: From 2006 to 2014, we reviewed 21,414 positive urine cultures for E. coli and Klebsiella sp. from a University hospital in the UK and found 1420 ESBL-positive specimens. Susceptibility testing was performed by British Society of Antimicrobial Chemotherapy disc diffusion testing. ESBL screening was performed on samples resistant to cefpodoxime and confirmed by double disc diffusion (Oxoid Ltd, Basingstoke, UK). Patient gender, age, inpatient status, and catheterisation were assessed as risk factors. RESULTS: ESBL production amongst E. coli urine cultures increased 44 %, from 4.6 to 6.6 % of all E. coli isolates. ESBL-positive organisms were associated with increases in drug resistance, particularly amongst fluoroquinolones, trimethoprim, and cephalexin. Multidrug resistance was a feature with 75 % of ESBL+ Klebsiella sp.-resistant ≥6 antibiotic classes. ESBL producers remained largely susceptible to carbapenems. Male gender, urinary catheterisation, inpatient status, and increasing age were identified as risk factors for ESBL infection or colonisation. CONCLUSION: We demonstrate that the incidence of ESBL-producing E. coli in urine cultures is increasing and that such isolates are multidrug resistant. Carbapenems and nitrofurantoin for E. coli infections remain effective, which may guide empirical antibiotic therapy.

Minimally invasive percutaneous nephrolithotomy in preschool age children with kidney calculi (including stones induced by melamine-contaminated milk powder).

PURPOSE: This study was undertaken to assess the safety and efficacy of minimally invasive percutaneous nephrolithotomy (mini-PCNL) using ureteroscope and pneumatic intracorporeal lithotripsy in preschool age children with kidney calculi. METHODS: We studied 27 renal units in 20 patients of preschool age (≤ 6 years) who underwent mini-PCNL at our institute. The mean age was 42.6 months (range 14-68 months). The average stone burden was 1.85 cm (range 0.9-2.8 cm). Eight patients aged 14 to 58 months had been exposed to melamine-tainted powdered formula. The mini-PCNL was performed with an X-ray-guided peripheral puncture. Minimal tract dilatation was undertaken to fit a 14-16 Fr peel-away sheath. Ureteroscope and pneumatic intracorporeal lithotripsy were used to fragment the stones. RESULTS: Complete clearance was achieved in 23 renal units (85.2 %) with mini-PCNL monotherapy. This has increased to 92.6 % after adjunctive ESWL. The average fall in hemoglobin was 1.28 g/dL. None of the patients required blood transfusion. The median length of hospital stay was 8.2 days. Patients were followed up every 6 months for 2 years. There has been only one recurrence of stone and no long-term complications. CONCLUSION: Mini-PCNL is a effective treatment for pediatric kidney stones refractory to extracorporeal shock wave lithotripsy, including stones induced by melamine-contaminated milk powder. The "mini-PCNL" technique, which uses ureteroscope and pneumatic intracorporeal lithotripsy, is a safe and feasible modality for treating renal calculi in preschool age children.

The 50-year history of the ice water test in urology.

PURPOSE: The ice water test was first described in a 1957 study of cold receptors in the bladder. We examined the role of the ice water test in the diagnosis and management of different urological conditions. MATERIALS AND METHODS: MEDLINE and PubMed literature searches were performed, spanning 1956 to January 2009. Other studies were identified by reviewing secondary references in the original citations. RESULTS: The ice water test has been shown to be a lower motoneuron segmental reflex involving C-fiber afferents, which are associated with cold receptors. A number of its clinical applications have been described. The test was first thought to be specific to upper motoneuron lesions but patients with other urological conditions have had a positive test, including those with nonneurogenic disorders. The test is almost always negative (contractions less than 15 cm H(2)O) in healthy volunteers and in patients with stress urinary incontinence, lower motoneuron conditions and bladder pain syndrome. In cases of upper motoneuron conditions the positive test rate is 46% to 92% depending on the underlying pathological condition. CONCLUSIONS: The ice water test has several potential applications but it is not needed in routine clinical practice. To date the main interest has been in patients with neurogenic bladder disorders. Further studies to investigate the validity and reliability of the ice water test in patients with idiopathic detrusor overactivity could prove useful.

Development of a Disease-Specific Ureteral Calculus Patient Reported Outcome Measurement Instrument.

INTRODUCTION: Patient reported outcome measures (PROMs) are powerful instruments to assess the impact of a disease on health from the patient's perspective. We describe the process of designing, testing, and validating the Cambridge Ureteral Stone PROM (CUSP). MATERIALS AND METHODS: Patients recently diagnosed with ureteral stones were approached for participation in focus groups, structured interviews, and test-retest validation studies. Statistical tests included Cronbach's alpha for internal consistency, Spearman's and Pearson's correlation coefficients for test-retest validity, permutation tests of equality of means and Spearman's correlation coefficients for discriminant validity. RESULTS: Forty-three patients participated in the development of the CUSP. Twenty-two patients were involved in the focus groups and structured interviews and a further 21 participated in the prospective test-retest study. Expressed comments were grouped into seven broad health domains: pain, fatigue, sleep disturbance, work and daily activities, anxiety, gastrointestinal (GI) symptoms, and urinary symptoms. Items were selected from established PROM platforms to form the draft (dCUSP) instrument, which was then used for test-retest validation and item reduction. All domains scored highly for Cronbach's alpha (>0.8), with the exception of GI symptoms. Large Spearman's (>0.76) and Pearson's correlation estimates (>0.83) were obtained for test-retest validity, suggesting that answers were reliable through the time period tested. The estimates of the Spearman's correlation coefficient between each pair of domains ranged from 0.17 to 0.78 and the upper bounds of the corresponding 95% confidence intervals were all smaller than 0.95, suggesting that each domain measures something different. The tests of equality of the mean of scores of the control (n = 25) and patient groups were all significant, suggesting that CUSP successfully discriminated patients suffering from ureteral stones for every domain. CONCLUSION: CUSP is a patient-derived ureteral stone PROM, which can be used to measure ureteral stone disease health outcomes from the patient's point of view.

Candida growth in urine cultures: a contemporary analysis of species and antifungal susceptibility profiles.

BACKGROUND: Recent publications suggest the distribution of Candida species causing candiduria may vary geographically, which has implications for the continued efficacy of antifungal therapy and emerging resistance. AIM: To investigate the incidence of Candiduria at a university hospital in the UK. Further, to assess the distribution of species and the accompanying antifungal susceptibility profile, in order to monitor the clinical utility of current antifungal treatment guidelines for candiduria so that patients receive the best possible outcomes from the most up to date care. DESIGN: Retrospective audit. METHODS: From 1st January 2005 to 31st October 2014, we retrospectively reviewed 37 538 positive urine cultures recorded in a computerized laboratory results database. Identification and susceptibility testing was performed using the VITEK® 2 fungal susceptibility card (bioMérieux, Marcy d'Etoile, France). RESULTS: In total, 96 cultures were positive for Candida species, of which 69 (72%) were C.albicans, which translates to a prevalence of 2.6 per 1000 positive urine cultures. Candiduria was more common in younger patients, males and catheterized females. We report 94 and 73% of isolates of C.albicans and other non-C.albicans Candida species were susceptible to fluconazole. All isolates were susceptible to amphotericin B. CONCLUSIONS: Our results add weight to the evidence supporting current European and North American guidelines recommending fluconazole or amphotericin B for treatment of candiduria, if antifungal treatment is clinically indicated.

Vancomycin resistant enterococci in urine cultures: Antibiotic susceptibility trends over a decade at a tertiary hospital in the United Kingdom.

PURPOSE: Enterococci are a common cause of urinary tract infection and vancomycin-resistant strains are more difficult to treat. The purpose of this surveillance program was to assess the prevalence of and determine the risk factors for vancomycin resistance in adults among urinary isolates of Enterococcus sp. and to detail the antibiotic susceptibility profile, which can be used to guide empirical treatment. MATERIALS AND METHODS: From 2005 to 2014 we retrospectively reviewed 5,528 positive Enterococcus sp. urine cultures recorded in a computerized laboratory results database at a tertiary teaching hospital in Cambridge, United Kingdom. RESULTS: Of these cultures, 542 (9.8%) were vancomycin resistant. No longitudinal trend was observed in the proportion of vancomycin-resistant strains over the course of the study. We observed emerging resistance to nitrofurantoin with rates climbing from near zero to 40%. Ampicillin resistance fluctuated between 50% and 90%. Low resistance was observed for linezolid and quinupristin/dalfopristin. Female sex and inpatient status were identified as risk factors for vancomycin resistance. CONCLUSIONS: The incidence of vancomycin resistance among urinary isolates was stable over the last decade. Although resistance to nitrofurantoin has increased, it still serves as an appropriate first choice in uncomplicated urinary tract infection caused by vancomycin-resistant Enterococcus sp.

Urinary TGF-1 has a supplementary value in predicting renal function recovery post unilateral ureteral obstruction.

PURPOSE: To evaluate whether urine transforming growth factor-ß1 (TGF-ß1) can help identifying kidneys that would recover their function after drainage of unilateral ureteric obstructive. METHODS: Forty-five patients with unilateral ureteral obstruction were included. Glomerular filtration rate (GFR) of the obstructed kidney was <10 ml/min, and all patients were treated with percutaneous nephrostomy. TGF-ß1 level was measured in the urine from the obstructed kidney at the time of drainage. GFR before nephrostomy insertion and 3 months after were calculated. RESULTS: Patients with renal function improvement (significant increase in GFR) after nephrostomy insertion had significantly lower concentration of urine TGF-ß1 (p<0.05) compared with the group that showed no change in GFR (non-functioning kidneys) The sensitivity, specificity and accuracy of urine TGF-ß1 in identifying non-functioning kidney was 82, 82 and 82%, respectively. CONCLUSIONS: Urine TGF-ß1 is a cytokine leading to renal fibrosis and has a supplementary value in differentiating, at early stage, between kidneys that would recover function after releasing unilateral ureteral obstruction from those which will not (non-functioning kidneys).

Natural history of detrusor contractility--minimum ten-year urodynamic follow-up in men with bladder outlet obstruction and those with detrusor.

OBJECTIVE: To check the long-term effect, in male patients, of treated and untreated bladder outlet obstruction (BOO) on detrusor contractility and to explore the relationship between ageing and detrusor underactivity (DUA). MATERIAL AND METHODS: Men investigated at the urodynamic department of Southmead Hospital in Bristol between 1972 and 1986 were traced and three groups were invited for repeat pressure-flow urodynamic studies (PFS). The first two groups included patients over 40 years old, with untreated or surgically treated BOO, and the third group had patients with DUA from all age groups. RESULTS: 196 patients (with a minimum 10 year gap from the first assessment) agreed to have repeat PFS. There was no statistically significant change in bladder contractility index (BCI) in patients with BOO treated by transurethral resection of the prostate (TURP) (mean difference in BCI was 0.01, 95% confidence interval -0.07 to 0.09, n=114). There was also no significant difference in BCI in untreated patients with BOO (p=0.10, n=53). The follow-up BCI was higher in untreated patients than in the surgically treated group. The BCI in patients with DUA did not change significantly after a minimum of 10 years' follow-up. CONCLUSIONS: There is no evidence to suggest that detrusor contractility declines with long-term BOO. Relieving the obstruction surgically does not improve the contractility. This is important when considering and counselling for TURP. Underactive detrusors remain underactive, but do not get worse with time, which could indicate that this is not an ageing process per se and may even have a congenital basis.

Photodynamic effect of 5-aminolevulinic acid-loaded nanoparticles on bladder cancer cells: a preliminary investigation.

OBJECTIVE: The aim of this study was to assess the photodynamic effect of nanoparticles loaded with a photosensitizing nanomedicine, 5-aminolevulinic acid (5-ALA), on T24 bladder cancer cells in vitro. MATERIAL AND METHODS: The nanoprecipitation technique was successfully used to prepare the drug-loaded polymeric nanoparticles. The drug loading rate and the drug loading efficiency were determined by ultraviolet spectrophotometry. The size and morphology of nanoparticles were detected using dynamic light scattering (DLS) and transmission electron microscopy. Cytotoxicity to T24 bladder cancer cells was assessed by coincubating 5-ALA-loaded nanoparticles of different concentrations with T24 bladder cancer cells. The cell growth inhibitory rate was measured after irradiation by a 650 nm wavelength diode laser. RESULTS: The drug loading rate of 5-ALA-loaded nanoparticles was 7% with a loading efficiency of 85%. The T24 cell growth inhibitory rates after incubation with 5.0, 10.0, 25.0 and 50.0 µg/ml 5-ALA-loaded nanoparticles were 73.19%, 79.95%, 83.86% and 89.74%, respectively, which demonstrated significantly higher cytotoxicity than those in the empty nanoparticle groups and 5-ALA free drug groups (p < 0.05). CONCLUSIONS: 5-ALA-loaded nanoparticles were successfully prepared and had a significantly enhanced photodynamic tumoricidal effect on bladder cancer cells in vitro.

The impact of obesity on urine composition and nephrolithiasis management.

BACKGROUND AND PURPOSE: Several studies have reported that obese patients have a higher risk of nephrolithiasis. The purpose of this study is to investigate the effect of overweight (OW) and obesity on stone composition, type of treatment, and urine composition. METHODS: With Institutional Review Board approval, charts of adult patients who attended our dedicated stone clinic over a 5-year period starting January 2006 were reviewed. Patients were categorized into normal (body mass index 18.5-24.9), OW (25-29.9), and obese (≥30). We excluded those who did not have at least one 24-hour urine analysis. RESULTS: OW and obese patients were more likely to have previous stones, more chance to have uric acid stones, and to be treated with shockwave lithotripsy in the community, and with ureteroscopy or percutaneous nephrolithotripsy in our center. They needed more thiazide diuretics, allopurinol, and dietitian counseling. They had statistically significant (P<0.05) higher urine calcium, citrate, supersaturation calcium phosphate, uric acid, supersaturation uric acid, sodium, potassium, magnesium, phosphorus, chloride, sulfate, urine urea nitrogen, protein catabolic rate, and creatinine compared with those with normal weight. CONCLUSION: OW and obese patients have different stone composition with increased excretion of stone promoters in the urine. Stone prevention measures should be introduced during metabolic syndrome evaluation.

Acute abdomen caused by bladder rupture attributable to neurogenic bladder dysfunction following a stroke: a case report.

INTRODUCTION: Spontaneous bladder rupture is a rare and serious event with high mortality. It is not often considered in the patient presenting with peritonitis. This often leads to delays in diagnosis. There are very few case reports of true spontaneous rupture in the literature. This is the first such reported case in which bladder rupture was attributable to neurogenic bladder dysfunction following a stroke. CASE PRESENTATION: We report the case of a 67-year-old Caucasian man who presented with lower abdominal pain and a peritonitic abdomen. He had a long-term urethral catheter because of urinary retention following a previous stroke. He was treated conservatively with antibiotics before a surgical opinion was sought. Exploratory laparotomy confirmed the diagnosis of spontaneous bladder rupture. After repair of the defect, he eventually made a full recovery. CONCLUSION: In this unusual case report, we describe an example of a serious event in which delays in diagnosis may lead to increased morbidity and mortality. To date, no unifying theory explaining why rupture occurs has been postulated. We conducted a thorough literature search to examine the etiological factors in other published cases. These etiological factors either increase intra-vesical pressure or decrease the strength of the bladder wall. We hope that by increasing awareness of these etiological factors, spontaneous bladder rupture may be diagnosed earlier and appropriate therapy started.

Urodynamic studies in the evaluation of the older man with lower urinary tract symptoms: when, which ones, and what to do with the results.

Lower urinary tract dysfunction is a major cause of morbidity and decreased quality of life in older men. Most urinary dysfunctions in the elderly are multifactorial in origin and associated with a broad spectrum of mental and physical conditions. In this population, it is essential to have a comprehensive assessment of the lower urinary tract, functional impairments and concurrent medical diseases. A holistic and individualized approach to management is important. Urodynamic studies (UDS) are objective tests which provide a major contribution to our understanding of the pathophysiology of lower urinary tract symptoms (LUTS). Urodynamic findings in older men may include common diagnoses such as bladder outlet obstruction and urinary incontinence. However, coexisting conditions such as detrusor overactivity and impaired detrusor contractility are common in older men. The identification of these conditions is necessary to appropriately counsel patients regarding treatment options. Simple urodynamic tests should be used whenever possible such as uroflowmetry and residual volume estimation. However, in complicated cases more invasive tests such as pressure flow studies are important to help choose the best treatment.

Does the patient's position influence the detection of detrusor overactivity?

AIMS: The demonstration of preoperative detrusor overactivity (DO) with associated overactive bladder symptoms (OAB) is known to have an adverse effect on surgery performed for stress incontinence or for prostatic obstruction. The purpose of this review is to examine the best position, when filling the bladder during urodynamics, to demonstrate detrusor overactivity and reproduce the OAB symptoms, when the demonstration of DO might be important. MATERIALS AND METHODS: MEDLINE and PUBMED literature searches were performed, spanning the period from 1956 to August 2005 using the keywords "detrusor overactivity" or "detrusor instability" combined with "posture or position or standing or sitting" and "urodynamics." Other studies were identified by reviewing secondary references in the original citations. RESULTS: Sixteen studies looked at the effect of position on the detection rate of DO. There is good consistency between the studies analyzed. All but two [Ramsden et al., Br J Urol 49:633-9, 1977; Choe et al., J Urol 161:1541-4, 1999] showed a clear effect, with an increase in DO when the patient is filled in the vertical position or is asked to sit or stand, with a full bladder, after being filled supine. Performing the urodynamics (UDS) in the supine position would have missed a large proportion of DO diagnoses ranging from 33% to 100%. CONCLUSIONS: This review confirms that the patient's position is a significant variable during urodynamics and that supine cystometry will fail to detect a significant percentage of patients with DO. We suggest that all patients should be filled sitting or standing, unless physically disabled. It seems desirable for the International Continence Society (ICS) to extend its "Good urodynamic practice guideline" [Schafer et al., Neurourol Urodyn 21:261-74, 2002] to cover this important issue.