Ultrasound guided ureteroscopy for the definitive management of ureteral stones: a randomized, controlled trial.

PURPOSE: Ureteroscopy is central to the surgical management of ureteral stones. Fluoroscopy is conventionally used for intraoperative guidance, although there is growing effort to decrease the exposure of patients and staff to ionizing radiation. We developed a radiation-free approach to ureteroscopy using ultrasound guidance to manage ureteral stones. To our knowledge we present the first randomized trial to study its safety and efficacy. MATERIALS AND METHODS: This single center, randomized clinical trial from 2011 to 2013 enlisted patients who presented with symptomatic ureteral stones 8 mm or less without a significant ipsilateral stone burden. Patients were randomly assigned to ultrasound or fluoroscopic guided ureteroscopy after temporizing ureteral stent placement. Intraoperative ultrasound guidance was performed using real-time imaging with the transducer placed at the patient flank to visualize the collecting system of the ipsilateral kidney. We compared operative time, stone size, stone-free status and complication rates between the 2 groups. RESULTS: A total of 50 patients were enrolled in study with 25 per arm. There was no difference in stone size (5.9 vs 5.7 mm), patient age (56 vs 52 years) or body mass index (31 vs 30 kg/m(2)) in the test group compared to controls. The ultrasound guidance cohort showed no significant difference in the stone-free rate (86% vs 86%) or the complication rate (8% vs 16%) compared to controls. Operative time was no longer in the ultrasound guidance cohort. CONCLUSIONS: In this feasibility study we found that ureteral stones may be definitively managed in a timely, effective and safe fashion without ionizing radiation in the general population using this novel technique of ultrasound guided ureteroscopy.

The effects of ambient temperature, humidity and season of year on urine composition in patients with nephrolithiasis.

UNLABELLED: Study Type--Prognosis (cohort series) Level of Evidence 2b. What's known on the subject? and What does the study add? Epidemiologic studies have shown that warmer climates are associated with increased incidence of nephrolithiasis. Many hypothesize that this is due to dehydration and lower urine volumes. The current study of stone formers reports that greater temperatures are associated with significant increases in urine calcium which may shed light on the mechanism underlying the increased stone incidence associated with increased ambient temperature. OBJECTIVE: • To understand the effects of temperature, humidity and season of year on 24-h urine composition in patients with nephrolithiasis. PATIENTS AND METHOD: • A retrospective review was performed of patients evaluated at four metabolic stone clinics. • Multivariate linear regression models examined the relationship between mean temperature, average humidity, season of year and 24-h urine composition. • Multivariate models adjusted for known risk factors for stone disease. • Mean temperature and average humidity data were obtained from http://www.weatherunderground.com based on patient-provided addresses. RESULTS: • A total of 599 patients were included in the study, comprising 239 women and 360 men with a mean age of 53.6 years (sd 15.0). • Mean temperature was 16.9 °C (sd 4.8, range -21.1 to 38.3 °C) and average humidity was 58.1% (sd 23.5, range 11-100%). • On multivariate linear regression, increasing temperature was associated with increasing urine calcium (ß = 11.3, 95% CI 2.2-20.0), super-saturation of calcium oxalate (ß = 0.6, 95% CI 0.2-0.9), super-saturation of calcium phosphate (ß = 0.14, 95% CI 0.03-0.2), and decreasing urine sodium (ß = -5.2, 95% CI -10.3 to -0.1). • As seasons become warmer (i.e. from winter to autumn to spring to summer), changes were increased urine volume (ß = 0.09, 95% CI 0.01-0.2) and decreased super-saturation of calcium phosphate (ß = -0.2, 95% CI -0.3 to -0.03). • There were no associations between quintile of humidity and any 24-h urine constituents. CONCLUSIONS: • Increasing temperature may increase stone risk by increasing urine excretion of calcium, and the super-saturation of calcium oxalate and calcium phosphate. • These findings were independent of humidity and of season of year. • This appears to be related to a physiological impact of temperature itself, rather than to geographic location.

Potential for control of detrusor smooth muscle spontaneous rhythmic contraction by cyclooxygenase products released by interstitial cells of Cajal.

Interstitial cells of Cajal (ICCs) have been identified as pacemaker cells in the upper urinary tract and urethra, but the role of ICCs in the bladder remains to be determined. We tested the hypotheses that ICCs express cyclooxygenase (COX), and that COX products (prostaglandins), are the cause of spontaneous rhythmic contraction (SRC) of isolated strips of rabbit bladder free of urothelium. SRC was abolished by 10 microM indomethacin and ibuprofen (non-selective COX inhibitors). SRC was concentration-dependently inhibited by selective COX-1 (SC-560 and FR-122047) and COX-2 inhibitors (NS-398 and LM-1685), and by SC-51089, a selective antagonist for the PGE-2 receptor (EP) and ICI-192,605 and SQ-29,548, selective antagonists for thromboxane receptors (TP). The partial agonist/antagonist of the PGF-2alpha receptor (FP), AL-8810, inhibited SRC by approximately 50%. Maximum inhibition was approximately 90% by SC-51089, approximately 80-85% by the COX inhibitors and approximately 70% by TP receptor antagonists. In the presence of ibuprofen to abolish SRC, PGE-2, sulprostone, misoprostol, PGF-2alpha and U-46619 (thromboxane mimetic) caused rhythmic contractions that mimicked SRC. Fluorescence immunohistochemistry coupled with confocal laser scanning microscopy revealed that c-Kit and vimentin co-localized to interstitial cells surrounding detrusor smooth muscle bundles, indicating the presence of extensive ICCs in rabbit bladder. Co-localization of COX-1 and vimentin, and COX-2 and vimentin by ICCs supports the hypothesis that ICCs were the predominant cell type in rabbit bladder expressing both COX isoforms. These data together suggest that ICCs appear to be an important source of prostaglandins that likely play a role in regulation of SRC. Additional studies on prostaglandin-dependent SRC may generate opportunities for the application of novel treatments for disorders leading to overactive bladder.

The influence of psychiatric comorbidities and sexual trauma on lower urinary tract symptoms in female veterans.

PURPOSE: We characterized the association of psychiatric comorbidities and sexual trauma with lower urinary tract symptoms in women. MATERIALS AND METHODS: Consecutive women (121) referred for evaluation of lower urinary tract symptoms to a specialized urology clinic were given validated questionnaires including the Urogenital Distress Inventory-6 and Incontinence Impact Questionnaire-7. These data were then analyzed according to psychiatric comorbidities, history of sexual trauma, age, race and obstetric history. Baseline incidence of psychiatric comorbidity and sexual trauma was also compared to a control population (1,298) from which all patients were referred. RESULTS: Women referred for evaluation of lower urinary tract symptoms had higher rates of psychiatric comorbidities (64.5% vs 25.9%, p <0.001) and sexual trauma (49.6% vs 20.1%, p <0.001) compared to those in the primary care clinic. Total survey scores for the Incontinence Impact Questionnaire-7 were significantly higher for patients with psychiatric comorbidities and sexual trauma (11.05 +/- 0.84) compared to scores of patients with neither of these conditions (7.6 +/- 1.02, p = 0.010). Stepwise multivariate regression analyses demonstrated that higher Urogenital Distress Inventory-6 scores were associated only with age younger than 50 years and history of miscarriage, and that higher Incontinence Impact Questionnaire-7 scores were associated only with psychiatric comorbidities and history of miscarriage. CONCLUSIONS: Psychiatric comorbidities and sexual trauma are prevalent in female veterans presenting for evaluation of lower urinary tract symptoms and psychiatric comorbidities are associated with greater quality of life impact.

Development of an Integrated Mobile Application for Evaluating Voiding Dysfunction: A Proof of Concept Study.

INTRODUCTION: Bladder voiding diaries are an important part of evaluating and managing lower urinary tract symptoms but are subject to poor data quality and diary completion rates. Mobile health technology is increasingly prevalent and can help overcome the problems of traditional paper and electronic diaries. METHODS: We identified proof of concept design principles based on a literature review and needs assessment. An electronic application was developed to improve self-assessment and symptom management for patients with voiding dysfunction. We analyzed application distribution and use patterns for 12 consecutive months. RESULTS: We designed an electronic application with complete mobile device integration containing a voiding diary, incontinence tracker and AUA Symptom Score questionnaire. Users could enter and modify details about the volume and frequency of voiding events, including leakage and pad use. Data could be electronically shared with providers. Integrating the application on the Apple® iOS and Android™ mobile operating systems eliminated the need for patients to carry or learn to use a separate device. During the 12-month study period 1,868 unique visitors from 18 countries downloaded the mobile application and made a total of 13,145 subsequent visits. CONCLUSIONS: This application for evaluating voiding dysfunction leverages mobile technology to overcome the limits of paper and standalone electronic formats. Domestic and international users downloaded the application and consistently logged return visits. Using mobile health in urology practices may help patients and providers better manage lower urinary tract symptoms and achieve improved control.

Ambulatory pathway laser prostate surgery in severely ill patients--feasibility and short-term outcomes.

OBJECTIVE: To assess readmissions, complications, and outcomes of a rapid ambulatory discharge pathway (RADP) in high anesthetic risk patients who have undergone laser prostate surgery. METHODS: Medical records of patients who underwent holmium laser ablation of the prostate between 2007 and 2012 by a single surgeon were retrospectively reviewed. Patients with American Society of Anesthesiologists category ≥3 ("severe systemic disease") were included. All patients were scheduled for a rapid ambulatory discharge pathway, which involved discharge on the day of surgery with a urethral catheter, with a voiding trial on postoperative day 3. RESULTS: Fifty-seven patients met the inclusion criteria. Fifty patients (88%) were successfully discharged on rapid ambulatory discharge pathway. Six patients (11%) were later readmitted for hematuria (3), urinary retention (1), or cardiac events (2). Two patients (4%) had emergency department visits for catheter-related problems. Increasing length of surgery, increasing amount of laser energy used, and a surgical indication indicative of more advanced disease were associated with postoperative hospitalization and readmissions on univariate analysis. No patient operated on for lower urinary tract symptoms was hospitalized or needed a readmission. The mean change in International Prostate Symptom Score and quality of life at 3 months were -12.5 ± 8.2 (P <.001) and -2.6 ± 1.7 (P <.001), respectively. CONCLUSION: It is safe to use a rapid ambulatory discharge pathway for laser prostatectomy in high anesthetic risk patients with good short-term outcomes, especially in men operated on for lower urinary tract symptoms.

It is safe to teach residents laser prostate surgery in the private practice setting.

OBJECTIVE: To examine the effect of resident involvement on laser prostate surgery outcomes within a urology group in a private practice setting. MATERIALS AND METHODS: Patients with ≥ 6 months of follow-up data who had undergone holmium laser ablation of the prostate by a single surgeon (R.L.Y.) within a private urology group were included in the present study. The patients were divided into 2 groups, with resident involvement in 1 group and no resident involvement in 1 group. The preoperative, intraoperative, and postoperative parameters were reviewed. The outcomes variables included changes in the International Prostate Symptom Score, quality of life scores, postvoid residual urine volumes, and reoperation rates. Statistical analysis used a 2-tailed Student t test with a significance level of .05. RESULTS: Of 153 holmium laser ablations of the prostate, 79 (52%) met the inclusion criteria. Of the 79 cases, 42 (53%) involved a resident. No statistically significant differences were found among the 2 groups in preoperative patient characteristics, including age, Society of Anesthesiologists score, prostate-specific antigen level, postvoid residual urine volume, International Prostate Symptom Score, or quality of life. The operative times were significantly longer in the resident group (57 vs 46 minutes, P = .05). Postoperatively, no differences in the mean values were found in postvoid residual urine volume (56 vs 64 mL, P = .73), change in International Prostate Symptom Score (11.5 vs 9.7, P = .44), change in quality of life score (-2.1 vs -1.3, P = .13), or reoperation rate (5% vs 11%, P = .19). CONCLUSION: The operative times were longer in the resident group, reflecting the inherent time taken to teach the residents the procedure. The results from the present study suggest that it is feasible to safely teach residents new surgical technology such as holmium laser ablation of the prostate in a nonacademic private practice setting without adversely affecting surgical performance or outcomes.

Insurance status, stone composition, and 24-hour urine composition.

UNLABELLED: Abstract Purpose: We examined the stone composition, 24-hour urinary risk factors, and insurance status in patients evaluated in two regional stone clinics to further investigate the relationship between the socioeconomic status and kidney stone formation. MATERIALS AND METHODS: We performed a retrospective review of stone formers who completed a 24-hour urinalysis as part of a metabolic evaluation for nephrolithiasis. Insurance status was determined by billing records and those with state-assisted insurance (SAI) were compared to patients with private insurance (PI). Multivariate analyses were performed adjusting for known risk factors for stones. RESULTS: Three hundred forty-six patients were included. Patients with SAI (16%) were significantly more likely to be female (55% vs.38%, p=0.026) and younger (43.5 vs.49.2, p=0.003). Among those with stone composition data (n=200), SAI patients were as likely to form calcium phosphate (CaPhos) as calcium oxalate (CaOx) stones (46.9% vs.31.3%, p=0.44). PI patients were significantly less likely to form CaPhos than CaOx stones (10.1% vs.77.4%, p<0.001). On multivariate analysis, among those with calcium stones, the odds of forming CaPhos stones over CaOx stones were ten times higher among SAI patients compared to PI, odds ratio 10.2 (95% CI 3.6, 28.6, p<0.001). Further, patients with SAI had significantly higher urine sodium, pH, and supersaturation of CaPhos, and a lower supersaturation of uric acid compared to patients with PI. CONCLUSIONS: SAI was associated with a greater likelihood of a CaPhos stone composition and increased urinary risk factors for CaPhos stones. These findings may reflect dietary or other unmeasured differences, and have important implications for resource allocation and counseling, as treatment may differ for these groups.

Successful transcloacal ureteral stent removal.

We report a percutaneous transcloacal approach for removal of a ureteral stent in a 15-year-old girl with a cloacal anomaly, spinal dysraphism, and complex pelvic anatomy, including a bicornuate uterus, reconstructed hindgut neobladder, and duplicated left pelvic kidney. The patient had undergone 3 previous unsuccessful attempts at stent removal, 2 endoscopic attempts by way of her neobladder, and 1 percutaneous transcloacal attempt before successful removal.

High dietary magnesium intake decreases hyperoxaluria in patients with nephrolithiasis.

OBJECTIVE: To examine the relationship between urine magnesium and hyperoxaluria in a cohort of patients with recurrent stone formation. METHODS: A total of 311 patients with nephrolithaisis were evaluated. The patients were divided into quintiles of urine magnesium excretion, an accepted surrogate of dietary magnesium intake. Multivariate analysis was used to examine the relationship between magnesium and hyperoxaluria. RESULTS: The mean patient age was 50.0 ± 14.9 years, the body mass index was 28.0 ± 5.9 kg/m(2), and 130 were women and 181 were men. The mean urine magnesium excretion was 100.8 ± 42.0 mg/d (range 17.8-224.8). On multivariate analysis, an increasing quintile of urine magnesium was associated with decreasing hyperoxaluria (ß = -0.37, 95% confidence interval -0.6 to -0.14, P < .05 for trend). When analyzed as separate quintiles with the lowest quintile of magnesium as the referent, only the greatest quintile demonstrated a statistically significant decrease in hyperoxaluria (ß = -1.7, 95% confidence interval -2.7 to -0.7, P < .05 for trend). CONCLUSION: Increasing magnesium intake was associated with decreasing hyperoxaluria in this population of patients with stone formation. Our findings showed that high magnesium intake might be required to observe clinically significant effects from magnesium.

Abnormalities of 24-hour urine composition in first-time and recurrent stone-formers.

OBJECTIVE: To examine differences in 24-hour urine composition between recurrent and first-time stone-formers. METHODS: A retrospective review of patients evaluated in 2 metabolic stone clinics was performed. Recurrent stone formation was defined as patients with a history of more than 1 stone episode and first-time stone-formers were those with a history of a single-stone episode. Frequencies of urine metabolic abnormalities were noted. Multivariate linear regression was performed to evaluate the likelihood of abnormalities of 24-hour urine composition. RESULTS: Three-hundred eleven patients met inclusion criteria: 71 (22.8%) were first-time stone-formers and 240 (77.1%) were recurrent stone-formers. On univariate analysis, the likelihood of having a single abnormality of 24-hour urine composition (ie, hypercalciuria, hyperoxaluria, hyperuricosuria, or hypocitraturia) was similar between the 2 groups (83.1% for first-time vs 88.8% for recurrent, P = NS). In addition, there were similar rates of hypercalciuria (39.4% vs 43.3%, P = NS), hyperoxaluria (32.4% vs 33.3%, P = NS), hyperuricosuria (29.6% vs 23.3%, P = NS), and hypocitraturia (45.0% vs 45.0%, P = NS). On multivariate logistic regression, there was no difference in detection of any urine abnormality (ie, hypercalciuria or hyperoxaluria or hypocitraturia or hyperuricosuria) between first-time (referent) or recurrent stone-formers (OR 1.68, 95% CI .8-3.5, P = .2). CONCLUSION: In this study, detection of urine abnormalities was similar in first-time and recurrent stone-formers. Given the strong patient preference for stone prevention and the high success of directed therapy in the literature, we believe it is not unreasonable to offer comprehensive metabolic evaluation to first-time stone-formers who express a desire to undergo evaluation.

Effect of socioeconomic status on 24-hour urine composition in patients with nephrolithiasis.

OBJECTIVE: To examine the relationship between the poverty and education levels and 24-hour urine composition in patients with nephrolithiasis because little is known about the relationship between socioeconomic status and kidney stone risk. METHODS: A retrospective review was performed of patients evaluated at 2 metabolic stone clinics. The poverty level (ie, percentage of those living below the poverty level) and education level (ie, percentage of those with a high school education or greater) for each postal code were determined from the U.S. Census Bureau data. Multivariate linear regression analysis was used to examine the relationship between the poverty and education levels and 24-hour urine composition. RESULTS: A total of 435 patients were included in the present study. Of the 435 patients, 173 were women and 262 were men (40% women), the mean age was 52.5 ± 14.4 years, and the mean body mass index was 28.6 ± 6.5 kg/m(2). The mean percentage of those below the poverty level was 8.2% ± 6.2%, and the mean percentage of those with a high school education or greater was 87.4% ± 7.4%. On multivariate linear regression analysis, an increasing local poverty level was associated with significant increases in urine calcium (ß = 1.51, 95% confidence interval [CI] 0.16-2.86). A decreasing local level of education (ie, decreasing percentage of those with a high school diploma or greater) was associated with significant increases in urine calcium (ß = 1.26, 95% CI 0.10-2.42), supersaturation of calcium oxalate (ß = 0.04, 95% CI 0.006-0.09), and supersaturation of calcium phosphate (ß = 0.013, 95% CI 0.0002-0.03). No other associations were found between the poverty and education levels and any urine constituents or supersaturations. CONCLUSION: In the present study of patients with stone formation, increasing poverty was associated with increased urine calcium, and increasing education appeared to be protective by decreasing urine calcium and the supersaturation of calcium oxalate and calcium phosphate. Additional studies are important to elucidate the mechanisms underlying these findings.

Relationship between glomerular filtration rate and 24-hour urine composition in patients with nephrolithiasis.

OBJECTIVE: To examine the relationship between GFR and 24-hour urine composition in patients with nephrolithiasis to understand how renal function may affect stone risk. Alterations in glomerular filtration rate (GFR) are associated with a number of physiological changes. METHODS: A retrospective, institutional review board-approved review of patients from 2 metabolic stone clinics was performed. One-way analysis of variance and multivariate linear regression models were used to evaluate the relationship between GFR quintile and 24-hour urine composition. RESULTS: A total of 403 patients (241 male, 162 female) with a mean age of 52.6 ± 14.2 years were included in the study. On univariate analysis, decreasing GFR by quintile was associated with significant reductions in urine calcium, citrate, supersaturation of calcium oxalate, and supersaturation of calcium phosphate (P < .05 for each). In multivariate linear regression models, decreasing GFR by quintile was associated with significant decreases in urine calcium (ß = -11.2, 95% CI = -18.3 to 4.01), urine citrate (ß = -32.4, 95% CI = -54.1 to 10.8), oxalate (ß = -1.83, 95% CI = -2.85 to 0.81), supersaturation of calcium oxalate (ß = -0.58, 95% CI = 0.84 to 0.33) and supersaturation of calcium phosphate (ß = -0.09, 95% CI = 0.17 to 0.02), as well as an increase in urine magnesium (ß = 3.40, 95% CI = 0.7 to 6.1). CONCLUSION: Reduction in GFR is associated with decreased urine calcium, oxalate, and citrate, and increased urine magnesium. These findings have implications for treatment of patients with stone disease and impaired renal function.