Michael Ordon

A Population Based Study of the Changing Demographics of Patients Undergoing Definitive Treatment for Kidney Stone Disease

PURPOSE We examined temporal changes in the demographics of patients undergoing definitive treatment for kidney stones during a 20-year period in Ontario, Canada. MATERIALS AND METHODS Using the Ontario Health Insurance Plan physician claims database and the Canadian Institute for Health Information Discharge Abstract Database we performed a population based cross-sectional time series analysis by identifying all kidney stone treatments done between July 1, 1991 and December 31, 2010. The demographics assessed were patient gender, age and socioeconomic status. The rate and/or proportion of kidney stone treatments per strata of these demographics were calculated for each 1-year block of the study period. We used time series analysis with exponential smoothing and autoregressive integrated moving average models to assess for trends with time. RESULTS We identified 116,115 patients who underwent treatment for kidney stones during the study period. The rate of stone procedures performed per year increased steadily from 85/100,000 to 126/100,000 population. With time the rate of females who were treated increased significantly from 40/100,000 to 53/100,000 (p <0.0001). In contrast, the rate of males who were treated remained stable, increasing from 82/100,000 to 83/100,000 (p = 0.11). In regard to age the rate of patients older than 64 years increased significantly with time from 67/100,000 to 89/100,000 (p <0.0001). In regard to socioeconomic status approximately 20% of the patients were in each of the 5 income quintiles during the entire study period. CONCLUSIONS Our population based study shows an increased rate of females and of patients older than 64 years undergoing definitive treatment for kidney stones with time.

A Prospective Study Examining the Incidence of Bacteriuria and Urinary Tract Infection After Shock Wave Lithotripsy with Targeted Antibiotic Prophylaxis

PURPOSE Controversy exists regarding antibiotic prophylaxis before shock wave lithotripsy. The AUA (American Urological Association) guideline recommends universal antibiotic prophylaxis, whereas the EAU (European Association of Urology) guideline recommends prophylaxis only for select patients. We evaluated the use of targeted antibiotic prophylaxis in preventing urinary tract infections in patients undergoing shock wave lithotripsy. MATERIALS AND METHODS A prospective single cohort study was performed during 6 months with patients undergoing shock wave lithotripsy. All patients underwent urine dipstick and culture before shock wave lithotripsy. Targeted antibiotic prophylaxis was provided at the discretion of the treating urologist. All patients had a urine culture performed after shock wave lithotripsy and completed a survey documenting fevers or urinary symptoms. The primary outcome was the incidence of urinary tract infections, urosepsis and asymptomatic bacteriuria after shock wave lithotripsy. The secondary outcome was the sensitivity and specificity of urinary dipstick leukocytes and nitrites. RESULTS A total of 526 patients were enrolled in the study. Of the 389 patients included in the determination of the primary outcome, urinary tract infection developed in only 1 (0.3%), urosepsis did not develop in any patients and asymptomatic bacteriuria developed in 11 (2.8%). Eight (2.1%) patients were administered antibiotic prophylaxis. The specificity of urine dipstick nitrites was high (95%) while the sensitivity was poor (9.7%). CONCLUSIONS In our cohort study using targeted antibiotic prophylaxis the rates of urinary tract infection after shock wave lithotripsy and rates of asymptomatic bacteriuria were extremely low, with no development of urosepsis. This finding questions the need for universal antibiotic prophylaxis before shock wave lithotripsy.

Third Place: Stones Lodge at Three Sites of Anatomic Narrowing in the Ureter: Clinical Fact or Fiction?

UNLABELLED Abstract Background and Purpose: Throughout the literature, the ureter is described as having three anatomic sites of narrowing at which kidney stones typically become lodged: The ureteropelvic junction (UPJ), the ureteral crossing of the iliac vessels, and the ureterovesical junction (UVJ). There is little evidence to support this notion, however. The purpose of our study is to evaluate whether three peaks in stone distribution corresponding to these anatomic landmarks exist. METHODS We retrospectively reviewed the kidneys-ureters-bladder (KUB) films of 622 patients with solitary ureteral calculi referred for shockwave lithotripsy (SWL). Pretreatment KUB films were used to categorize the location of their ureteral stone relative to 1 of 19 levels referenced to the axial skeleton. CT scans of 74 patients were used to determine the location of the UPJ, ureteral crossing of the iliac vessels, and UVJ relative to the 19 levels on KUB radiography. Histograms were then constructed to plot the distribution of stones within the ureter relative to these 19 levels. The effect of sex, stone size and side, and presence of a stent on stone distribution were analyzed. RESULTS There are two peaks in the distribution of stones within the ureter in patients referred for SWL that correspond to the UPJ/proximal ureter and intramural ureter/UVJ. In patients with larger stones (≥100 mm(2)) or a ureteral stent in place, stones were distributed more proximally (P<0.0001). When comparing sexes, there was a difference in stone distribution that approached significance (P=0.0523), with a greater peak more distally in males compared with females. CONCLUSIONS Our review demonstrates a peak in the distribution of stones corresponding to the UPJ/proximal ureter and the intramural ureter/UVJ. We failed to demonstrate a peak in stone distribution corresponding with the ureteral crossing of the iliac vessels.

Does surgical "warming up" improve laparoscopic simulator performance?

Introduction The objective of this study was to determine if preoperative warming up by obstetrics and gynecology trainees, using a validated bench model for intracorporeal suturing, improves efficiency, precision, and quality of laparoscopic suturing. Methods A randomized crossover design was used. Fourteen obstetrics and gynecology residents were randomized [3 junior (year 2) and 11 senior (years 3–5) residents]. Participants were randomized to warm-up or no warm-up and then acted as their own controls at least 2 weeks later. Warm-up consisted of the use of a laparoscopic bench model to practice intracorporeal suturing for 15 minutes. All participants performed a prevalidated intracorporeal suturing task (after either warm-up or no warm-up), which was scored based on time, precision, and knot strength. Each participant also completed a questionnaire anonymously to determine if they believed that warming up improved their performance, regardless of the score they received. Results Thirteen participants completed the study. There was no difference in score when warm-up was compared with no warm-up for the group as a whole. When the junior residents were excluded from the analysis, however, analysis of variance showed a significant improvement in score only when a warm-up was completed in the second session (P = 0.022). The questionnaire revealed that 81.8% of participants felt that warming up subjectively improved their ability, independent of their actual score. Conclusions This study demonstrates that a preoperative warm-up, combined with repetition, is beneficial in improving senior obstetrics and gynecology residents’ laparoscopic suturing performance. This demonstrates a novel approach to resident education for teaching advanced laparoscopic skills.

Hormone abnormalities are not related to the erectile dysfunction and decreased libido found in many men with infertility

OBJECTIVE To evaluate whether hormonal markers predict erectile dysfunction (ED) and symptoms of T deficiency syndrome (TDS), which are commonly found in the population of infertile men. DESIGN Retrospective study utilizing a prospectively maintained infertility database. SETTING A tertiary referral center. PATIENT(S) A total of 1,750 of 2,783 men presenting for evaluation of infertility between 1995 and 2010 completed validated questionnaires. INTERVENTION(S) Androgen Deficiency in the Aging Male (ADAM) and Sexual Health Inventory for Men questionnaires were administered. Baseline risk factors for ED and TDS were also measured. Subjects underwent serum hormone evaluation for total T, calculated bioavailable T, sex hormone-binding globulin, E2, LH, FSH, and PRL. MAIN OUTCOME MEASURE(S) Multivariable logistic regression modeling was used to determine the significance of hormonal markers in predicting ED (Sexual Health Inventory for Men score <22) and/or a positive ADAM score. RESULT(S) The prevalence of ED and a positive response to the ADAM questionnaire were 30.5% and 45.2%, respectively, in this population (mean age, 36 years). Low serum T (total T < 10 nmol/L) was found in 29.4%. Neither T nor bioavailable T was significantly associated with the symptoms of ED or TDS on multivariable regression analysis. CONCLUSION(S) Erectile dysfunction and TDS in young, infertile men seem to be unrelated to hormone changes.

Profilin-1 expression is associated with high grade and stage and decreased disease-free survival in renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is associated with high mortality, although individual outcomes are highly variable. Identification of patients with increased risk of disease progression can guide customizing management plan according to disease severity. Profilin-1 (Pfn1) has been recently identified as overexpressed in metastatic ccRCC compared with primary tumors. We examined Pfn1 expression in a tissue microarray of 384 cases of histologically confirmed primary ccRCC with detailed clinical follow-up. Profilin-1 expression showed both cytoplasmic and nuclear staining patterns. The immunoexpression of Pfn1 was scored in a semiquantitative fashion. There was no significant difference in Pfn1 expression between normal kidney and kidney ccRCC. Our results show that strong cytoplasmic Pfn1 expression is associated with high-grade (P < .001) and high-stage (III-IV) (P = .018) disease. Univariate analysis of the data set showed that higher Pfn1 expression is associated with significantly shorter disease-free survival (hazard ratio 7.36, P = .047) and also lower overall survival. Kaplan-Meier analysis showed that high cytoplasmic expression of Pfn1 was also associated with a statistically significant lower disease-free survival (P = .018). It was also associated with lower overall survival, although this was not statistically significant. Profilin-1 lost its prognostic significance in the multivariate analysis when controlling for grade and stage. Profilin-1 expression was not associated with significant prognostic deference in the subgroup of patients with stage 1 disease. Our results suggest that the evaluation of Pfn1 by immunohistochemistry may help to identify patients with an increased risk of disease progression. We validated our results at the messenger RNA level on an independent patient cohort. Higher messenger RNA expression of Pfn1 is associated with significantly lower survival.

Exosomal MicroRNAs Are Diagnostic Biomarkers and Can Mediate Cell–Cell Communication in Renal Cell Carcinoma

BACKGROUND Apart from an invasive biopsy, currently no tools are available to confirm the diagnosis of clear cell renal cell carcinoma (ccRCC); this resulted in approximately 30% of patients being diagnosed with metastatic disease. OBJECTIVE To determine whether urinary microRNAs (miRNAs) can serve as biomarkers to confirm the diagnosis of ccRCC. DESIGN, SETTING, AND PARTICIPANTS Global miRNA expression was assessed in 28 preoperative urine samples from patients with ccRCC and 18 healthy participants. The independent validation set consisted of 81 ccRCC patients, 24 patients with benign lesions, and 33 healthy participants. We extracted both cell-free and exosomal RNA for miRNA expression analysis using miRNA-specific polymerase chain reaction assays. We also investigated exosomal miRNA secretion in cell line models and performed exosome transfer between RCC and endothelial cell types. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Receiver operating characteristic analysis was applied to identify the discrimination power of miRNAs. RESULTS AND LIMITATIONS Overall, miR-126-3p combined with miR-449a or with miR-34b-5p could significantly distinguish ccRCC patients from healthy participants (miR-126-3p-miR-449a: area under the curve [AUC]: 0.84; 95% confidence interval [CI], 0.7620-0.9151; p<0.001; miR-126-3p-miR-34b-5p: AUC: 0.79; 95% CI, 0.7013-0.8815; p<0.001). The combination of miR-126-3p and miR-34b-5p was also able to distinguish small renal masses (pT1a, ≤4cm) from healthy controls (AUC: 0.79; 95% CI, 0.6848-0.8980; p<0.001). Using miR-126-3p and miR-486-5p in combination, we were able to differentiate between benign lesions and ccRCC (AUC: 0.85; 95% CI, 0.7295-0.9615; p<0.01). The expression of a number of miRNAs returned to a level comparable with health after surgery. Kidney cancer cell lines were found to secrete exosomal miR-126-3p, miR-17-5p, miR-21-3p, and miR-25-3p, and these miRNAs were found to be internalized by other cell types. CONCLUSIONS We identified exosomal miRNAs as potential noninvasive diagnostic urinary biomarkers for ccRCC and provided evidence that miRNAs are secreted by the tumor and can function as a tool for intercellular communication. PATIENT SUMMARY We identified urinary microRNAs that can serve as diagnostic biomarkers for clear cell renal cell carcinoma.

Intra-corporeal robotic renal auto-transplantation

Renal auto-transplantation (RATx) is a suitable option for managing patients with long upper ureteric or pan-ureteric strictures. The current gold standard approach to RATx is a laparoscopic nephrectomy followed by open auto-transplantation. The advent of robotic-assisted laparoscopic surgery has allowed us to apply minimally-invasive techniques to ever-more complex surgical procedures. We present the case of a 38-year-old patient referred to our institution for management of a failed laparoscopic pyeloplasty resulting in a long upper ureteric stricture with complete ureteric obstruction. After complete evaluation, RATx was determined as a suitable management option. Completely intracorporeal right RATx was performed robotically with intraperitoneal cold perfusion. Total operative time was 6.5 hours, with total ischemia time of only 79 minutes (4 minutes warm ischemia, 48 minutes cold ischemia, 27 minutes re-warming time), comparable to the gold standard approach for RATx. To our knowledge, this is the first reported case of a completely intracorporeal robotic RATx in Canada.

Ureteritis Cystica: A Rare Cause of Ureteral Obstruction

Ureteritis cystica is a rare, but recognized cause of ureteral obstruction. To our knowledge, we present the first case where obstruction secondary to the cystic component is confirmed with a functional study. Additionally, we present high-quality radiologic and endoscopic images of two cases of ureteritis cystica.

Simulation-based flexible ureteroscopy training using a novel ureteroscopy part-task trainer

INTRODUCTION Simulation-based training (SBT) is being increasingly used for novice trainees as a means of overcoming the early learning curve associated with new surgical skills. We designed a SBT flexible ureteroscopy (fURS) course using a novel inanimate training model (Cook Medical, Bloomington, IN; URS model). We evaluated the course and validated this Cook URS model. METHODS A 2-week SBT fURS course was designed for junior level urology trainees at 2 Canadian universities. The curriculum included didactic lectures, hands-on training, independent training sessions with expert feedback, and use of the Cook URS part-task model. Baseline and post-course assessments of trainee fURS skills were conducted using a standardized test task (fURS with basket manipulation of a calyceal stone). Performances were video-recorded and reviewed by 2 blinded experts using a validated assessment device. RESULTS Fifteen residents (postgraduate years [PGY] 0-3) participated in the course. Of the participants, 80% rated the Cook URS model as realistic (mean = 4.2/5) and 5 endourology experts rated it as useful as a training device (mean = 4.9/5), providing both face and content validity. The mean overall performance scores, task completion times, and passing ratings correlated with trainee clinical fURS experience - demonstrating construct validity for the Cook URS model. The mean post-course task completion times (15.76 vs. 9.37 minutes, p = 0.001) and overall performance scores (19.20 vs. 25.25, p = 0.007) were significantly better than at baseline. Post-course performance was better in all domains assessed by the validated assessment device. CONCLUSIONS This study demonstrates that a SBT curriculum for fURS can lead to improved short-term technical skills among junior level urology residents. The Cook URS model demonstrated good face, content and construct validity.