Removal of Small, Asymptomatic Kidney Stones and Incidence of Relapse.

BACKGROUND: The benefits of removing small (≤6 mm), asymptomatic kidney stones endoscopically is unknown. Current guidelines leave such decisions to the urologist and the patient. A prospective study involving older, nonendoscopic technology and some retrospective studies favor observation. However, published data indicate that about half of small renal stones left in place at the time that larger stones were removed caused other symptomatic events within 5 years after surgery. METHODS: We conducted a multicenter, randomized, controlled trial in which, during the endoscopic removal of ureteral or contralateral kidney stones, remaining small, asymptomatic stones were removed in 38 patients (treatment group) and were not removed in 35 patients (control group). The primary outcome was relapse as measured by future emergency department visits, surgeries, or growth of secondary stones. RESULTS: After a mean follow-up of 4.2 years, the treatment group had a longer time to relapse than the control group (P<0.001 by log-rank test). The restricted mean (±SE) time to relapse was 75% longer in the treatment group than in the control group (1631.6±72.8 days vs. 934.2±121.8 days). The risk of relapse was 82% lower in the treatment group than the control group (hazard ratio, 0.18; 95% confidence interval, 0.07 to 0.44), with 16% of patients in the treatment group having a relapse as compared with 63% of those in the control group. Treatment added a median of 25.6 minutes (interquartile range, 18.5 to 35.2) to the surgery time. Five patients in the treatment group and four in the control group had emergency department visits within 2 weeks after surgery. Eight patients in the treatment group and 10 in the control group reported passing kidney stones. CONCLUSIONS: The removal of small, asymptomatic kidney stones during surgery to remove ureteral or contralateral kidney stones resulted in a lower incidence of relapse than nonremoval and in a similar number of emergency department visits related to the surgery. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and the Veterans Affairs Puget Sound Health Care System; ClinicalTrials.gov number, NCT02210650.).

Prospective Multicenter Evaluation of Pain Before and After Removal of Nonobstructing Renal Calculi: A CoRE Initiative.

PURPOSE: Flank pain associated with stone disease is typically caused by a stone that obstructs urine flow. However, it is plausible that nonobstructing kidney stones may still cause pain. We performed a multicenter, observational trial to evaluate whether treatment of small nonobstructing calyceal stones improves pain and kidney stone-specific health-related quality of life. MATERIALS AND METHODS: Patients aged 18 years or older with nonobstructing renal stone(s) up to 10 mm in longest diameter and moderate to severe pain were recruited. All participants completed 3 questionnaires: the Brief Pain Inventory (BPI), the Patient-Reported Outcomes Measurement Information System pain interference form 6a, and the Wisconsin Stone Quality of Life questionnaire. Thereafter, all participants underwent ureteroscopy for renal stone treatment. All 3 questionnaires were repeated at 2, 6 to 8, and at 12 weeks postprocedure. The primary outcomes were change in preoperative to 12-week postoperative mean BPI score and worst BPI pain score. RESULTS: A total of 43 patients with nonobstructing kidney stones and associated flank pain were recruited. All stones were removed. Preoperatively, BPI scores for mean pain and worst pain were 5.5 and 7.2, respectively which decreased to 1.8 and 2.8 respectively at 12 weeks postoperatively. Wisconsin Stone Quality of Life questionnaire mean score increased from 70.4 to 115.3 at 12 weeks postoperatively. A total of 86% and 69% of patients had at least a 20% and 50% reduction in their mean pain scores, respectively. CONCLUSIONS: This study determined that patients benefit significantly from the removal of calyceal nonobstructing kidney stones for at least 12 weeks with a reduction in pain and an increase in quality of life. Therefore, surgical removal of these stones in this patient population should be offered as a treatment option.

Development of a burst wave lithotripsy system for noninvasive fragmentation of ureteroliths in pet cats.

BACKGROUND: Upper urinary tract stones are increasingly prevalent in pet cats and are difficult to manage. Surgical procedures to address obstructing ureteroliths have short- and long-term complications, and medical therapies (e.g., fluid diuresis and smooth muscle relaxants) are infrequently effective. Burst wave lithotripsy is a non-invasive, ultrasound-guided, handheld focused ultrasound technology to disintegrate urinary stones, which is now undergoing human clinical trials in awake unanesthetized subjects. RESULTS: In this study, we designed and performed in vitro testing of a modified burst wave lithotripsy system to noninvasively fragment stones in cats. The design accounted for differences in anatomic scale, acoustic window, skin-to-stone depth, and stone size. Prototypes were fabricated and tested in a benchtop model using 35 natural calcium oxalate monohydrate stones from cats. In an initial experiment, burst wave lithotripsy was performed using peak ultrasound pressures of 7.3 (n = 10), 8.0 (n = 5), or 8.9 MPa (n = 10) for up to 30 min. Fourteen of 25 stones fragmented to < 1 mm within the 30 min. In a second experiment, burst wave lithotripsy was performed using a second transducer and peak ultrasound pressure of 8.0 MPa (n = 10) for up to 50 min. In the second experiment, 9 of 10 stones fragmented to < 1 mm within the 50 min. Across both experiments, an average of 73-97% of stone mass could be reduced to fragments < 1 mm. A third experiment found negligible injury with in vivo exposure of kidneys and ureters in a porcine animal model. CONCLUSIONS: These data support further evaluation of burst wave lithotripsy as a noninvasive intervention for obstructing ureteroliths in cats.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery for treatment of renal stones in adults.

BACKGROUND: Kidney stones (also called renal stones) can be a source of pain, obstruction, and infection. Depending on size, location, composition, and other patient factors, the treatment of kidney stones can involve observation, shock wave lithotripsy, retrograde intrarenal surgery (RIRS; i.e. ureteroscopic approaches), percutaneous nephrolithotomy (PCNL), or a combination of these approaches. OBJECTIVES: To assess the effects of percutaneous nephrolithotomy (PCNL) versus retrograde intrarenal surgery (RIRS) for the treatment of renal stones in adults. SEARCH METHODS: We performed a comprehensive search of the Cochrane Library, MEDLINE, Embase, Scopus, and two trials registries up to 23 March 2023. We applied no restrictions on publication language or status. SELECTION CRITERIA: We included randomized controlled trials that evaluated PCNL (grouped by access size in French gauge [Fr] into three groups: ≥ 24 Fr [standard PCNL], 15-23 Fr [mini-PCNL and minimally invasive PCNL], and < 15 Fr [ultra-mini-, mini-micro-, super-mini-, and micro-PCNL]) versus RIRS. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies and extracted data from the included studies. Our primary outcomes were stone-free rate, major complications, and need for secondary interventions. Our main secondary outcomes were unplanned medical visits to emergency/urgent care or outpatient clinic, length of hospital stay, ureteral stricture or injury, and quality of life. We performed statistical analyses using a random-effects model. We rated the certainty of evidence using GRADE criteria. We adopted a minimally contextualized approach with predefined thresholds for minimal clinically important differences (MCIDs). MAIN RESULTS: We included 42 trials assessing the effects of PCNL versus RIRS in 4571 randomized participants. Twenty-two studies were published as full-text articles, and 20 were published as abstract proceedings. The average size of stones ranged from 10.1 mm to 39.1 mm. Most studies did not report sources of funding or conflicts of interest. The main results for the most important outcomes are summarized below. Stone-free rate PCNL compared with RIRS may improve stone-free rates (risk ratio [RR] 1.13, 95% confidence interval [CI] 1.08 to 1.18; I2 = 71%; 39 studies, 4088 participants; low-certainty evidence). Based on 770 participants per 1000 being stone-free with RIRS, this corresponds to 100 more (62 more to 139 more) stone-free participants per 1000 with PCNL (an absolute difference of 10%, where the predefined MCID was 5%). Major complications PCNL compared with RIRS probably has little or no effect on major complications (RR 0.86, 95% CI 0.59 to 1.25; I2 = 15%; 34 studies, 3649 participants; moderate-certainty evidence). Based on 31 complications in the RIRS group, this corresponds to six fewer (13 fewer to six more) major complications per 1000 with PCNL (an absolute difference of 0.6%, where the predefined MCID was 2%). Need for secondary interventions PCNL compared with RIRS may reduce the need for secondary interventions (RR 0.31, 95% CI 0.17 to 0.55; I2 = 61%; 21 studies, 2005 participants; low-certainty evidence). Based on 222 secondary interventions in the RIRS group, this corresponds to 153 fewer (185 fewer to 100 fewer) secondary interventions per 1000 with PCNL (an absolute difference of 15.3%, where the predefined MCID was 5%). Unplanned medical visits No studies reported unplanned medical visits. Length of hospital stay PCNL compared with RIRS may extend length of hospital stay (mean difference 1.04 days more, 95% CI 0.27 more to 1.81 more; I2 = 100%; 26 studies, 2804 participants; low-certainty evidence). This effect size is greater than the predefined MCID of one day. Ureteral stricture or injury PCNL compared with RIRS may have little or no effect on the occurrence of ureteral strictures (RR 0.93, 95% CI 0.39 to 2.21; I2 = 0%; 13 studies, 1574 participants; low-certainty evidence). Based on 14 ureteral strictures in the RIRS group, this corresponds to one fewer (nine fewer to 17 more) ureteral strictures per 1000 with PCNL (an absolute difference of 0.1%, where the predefined MCID was 2%). Quality of life No studies reported quality of life. AUTHORS' CONCLUSIONS: Based on a large body of evidence from 42 trials, we found that PCNL compared with RIRS may improve stone-free rates and may reduce the need for secondary interventions, but probably has little or no effect on major complications. PCNL compared with RIRS may have little or no effect on ureteral stricture rates and may increase length of hospital stay. We found no evidence on unplanned medical visits or participant quality of life. Because of the considerable shortcomings of the included trials, the evidence for most outcomes was of low certainty. Access size for PCNL was less than 24 Fr in most studies that provided this information. We expect the findings of this review to be helpful for shared decision-making about management choices for individuals with renal stones.

Tranexamic acid for percutaneous nephrolithotomy.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is the gold standard for the treatment of large kidney stones but comes with an increased risk of bleeding compared to other treatments, such as ureteroscopy and shock wave lithotripsy. Tranexamic acid (TXA) is an antifibrinolytic agent that has been used to reduce bleeding complications in other settings. OBJECTIVES: To assess the effects of TXA in individuals with kidney stones undergoing PCNL. SEARCH METHODS: We performed a comprehensive literature search of the Cochrane Library, PubMed (including MEDLINE), Embase, Scopus, Global Index Medicus, trials registries, other sources of the grey literature, and conference proceedings. We applied no restrictions on the language of publication nor publication status. The latest search date was 11 May 2023. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared treatment with PCNL with administration of TXA to placebo (or no TXA) for patients ≥ 18 years old. DATA COLLECTION AND ANALYSIS: Two review authors independently classified studies and abstracted data. Primary outcomes were: blood transfusion, stone-free rate (SFR), and thromboembolic events (TEEs). Secondary outcomes were: adverse events (AEs), secondary interventions, major surgical complications, minor surgical complications, unplanned hospitalizations or readmissions, and hospital length of stay (LOS). We performed statistical analyzes using a random-effects model. We rated the certainty of evidence (CoE) according to the GRADE approach using a minimally contextualized approach with predefined thresholds for minimally clinically important differences (MCIDs). MAIN RESULTS: We analyzed 10 RCTs assessing the effect of systemic TXA in PCNL versus placebo (or no TXA) with 1883 randomized participants. Eight studies were published as full text. One was published in abstract proceedings, but it was separated into two separate studies for the purpose of our analyzes. Average stone surface area ranged 3.45 to 6.62 cm2. We also found a single RCT published in full text assessing the effects of topical TXA in PCNL versus placebo (or no TXA) with 400 randomized participants, the results of which are further described in the review. Here we focus only on the results of TXA used systemically. Blood transfusion - Based on a representative baseline risk of 5.7% for blood transfusions taken from a large presentative observational studies, systemic TXA may reduce blood transfusions (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.27 to 0.76; I2 = 28%; 9 studies, 1353 participants; low CoE). We assumed an MCID of ≥ 2%. Based on 57 participants per 1000 with placebo (or no TXA) being transfused, this corresponds to 31 fewer (from 42 fewer to 14 fewer) participants being transfused per 1000. Stone-free rate - Based on a representative baseline risk of 75.7% for SFR, systemic TXA may increase SFRs (RR 1.11, 95% CI 0.98 to 1.27; I2 = 62%; 4 studies, 603 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 757 participants per 1000 being stone free with placebo (or no TXA), this corresponds to 83 more (from 15 fewer to 204 more) stone-free participants per 1000. Thromboembolic events - There is probably no difference in TEEs (risk difference (RD) 0.00, 95% CI -0.01 to 0.01; I2 = 0%; 6 studies, 841 participants; moderate CoE). We assumed an MCID of ≥ 2%. Since there were no thromboembolic events in intervention and/or control groups in 5 out of6 studies, we opted to assess a risk difference with systemic TXA for this outcome. Adverse events - Systemic TXA may increase AEs (RR 5.22, 95% CI 0.52 to 52.72; I2 = 75%; 4 studies, 602 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 23 participants per 1000 with placebo (or no TXA) having an adverse event, this corresponds to 98 more (from 11 fewer to 1000 more) participants with adverse events per 1000. Secondary interventions - Systemic TXA may have little to no effect on secondary interventions (RR 1.15, 95% CI 0.84 to 1.57; I2 = 0%; 2 studies, 319 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 278 participants per 1000 with placebo (or no TXA) having a secondary intervention, this corresponds to 42 more (from 44 fewer to 158 more) participants with secondary interventions per 1000. Major surgical complications - Based on a representative baseline risk for major surgical complications of 4.1%, systemic TXA may reduce major surgical complications (RR 0.36, 95% CI 0.21 to 0.62; I2 = 0%; 5 studies, 733 participants; moderate CoE). We assumed an MCID of ≥ 2%. Based on 41 participants per 1000 with placebo (or no TXA) having a major surgical complication, this corresponds to 26 fewer (from 32 fewer to 16 fewer) participants with major surgical complications per 1000. Minor surgical complications - Systemic TXA may reduce minor surgical complications (RR 0.71, 95% CI 0.45 to 1.10; I2 = 76%; 5 studies, 733 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 396 participants per 1000 with placebo (or no TXA) having a minor surgical complication, this corresponds to 115 fewer (from 218 fewer to 40 more) participants with minor surgical complications per 1000. Unplanned hospitalizations or readmissions - We are very uncertain how unplanned hospitalizations or readmissions are affected (RR 1.55, 95% CI 0.45 to 5.31; I2 = not applicable; 1 study, 189 participants; very low CoE). We assumed an MCID of ≥ 2%. Hospital length of stay - Systemic TXA may reduce hospital LOS (mean difference 0.52 days lower, 95% CI 0.93 lower to 0.11 lower; I2 = 98%; 7 studies, 1151 participants; low CoE). We assumed an MCID of ≥ 0.5 days. AUTHORS' CONCLUSIONS: Based on 10 RCTs with substantial methodological limitations that lowered all CoE of effect, we found that systemic TXA in PCNL may reduce blood transfusions, major and minor surgical complications, and hospital LOS, as well as improve SFRs; however, it may increase AEs. We are uncertain about the effects of systemic TXA on other outcomes. Findings of this review should assist urologists and their patients in making informed decisions about the use of TXA in the setting of PCNL.

Beyond medical expulsive therapy: evolution to supported stone passage for ureteric stones.

OBJECTIVE: To evaluate the impact of removing tamsulosin from standardized ureteric stone clinical protocols on rate of stone surgery. PARTICIPANTS AND METHODS: We conducted a single-centre, comparison of all patients with unilateral, <1 cm ureteric stones presenting to a stone clinic after discharge from the emergency department during consecutive years. In the initial year, patients were initially offered medical expulsive therapy (MET) with tamsulosin. In the subsequent year, the protocol was modified to focus on symptom control without tamsulosin; this was termed 'supported stone passage' (SSP). The primary outcome was rate of stone surgery within 90 days of the initial clinic encounter. RESULTS: Among 723 patients (360 MET, 363 SSP), the rate of attempted stone passage increased from 65% to 74%, between the initial and the subsequent year (P < 0.016). Tamsulosin prescription in patients to attempting stone passage decreased from 84% to 13% (P < 0.001). In patients attempting stone passage, the rate of stone surgery was 26% in the METand 19% in the SSP group (P = 0.066). The overall surgery rate decreased from 51% in the MET group to 40% in the SSP group (P = 0.003). Multivariable analysis, controlling for age, sex and stone burden, did not demonstrate a difference in either rate of attempting to pass stones or in rate of failure of passage according to care protocol. We were unable to demonstrate an independent effect of tamsulosin on failure of passage. Overall, surgical intervention was less likely in the SSP phase than in the MET phase, with an odds ratio of 0.64 (confidence interval) 0.44-0.91; P = 0.013). CONCLUSIONS: Removing tamsulosin from clinical protocols did not impair stone passage in patients attempting to pass stones.

Perceptions of dietary factors promoting and preventing nephrolithiasis: a cross-sectional survey.

OBJECTIVE: To assess knowledge of both promoting and preventive dietary factors on nephrolithiasis in a diverse patient population. Precipitating factors of kidney stone disease include diet, lifestyle, socioeconomic status, and race/ethnicity. However, patient awareness of these influences is poorly described. MATERIALS AND METHODS: A 24-question survey, assessing intake-related risk factors for stone disease, was administered prospectively to 1018 patients. Responses were summarized with frequency and percent. Statistical comparisons were made using a propensity scoring method in order to account for potential confounding variables. Propensity scores were stratified into quintiles. Further analysis with multiple imputation was performed to account for any missing data in the survey. The results of the propensity-adjusted log-binomial regression model are presented as prevalence ratios (PRs) and 95% confidence intervals (CIs). RESULTS: Respondents demonstrated limited knowledge of nutrient factors that influence stone development. However, most study participants (70.3%) reported a willingness to make lifestyle changes aimed at lowering their risk for stone disease. Respondents reporting previous nephrolithiasis education were less likely to report that diet had no effect on kidney stone formation (PR = 0.795, 95% CI 0.65, 0.96, p = 0.01) The type of physician who counseled the respondent had no association with patient knowledge for stone disease (PR = 0.83, 95% CI 0.63, 1.10, p = 0.2). CONCLUSIONS: Knowledge of diet-related risk factors for nephrolithiasis is limited among this population. Respondents who received prior education appeared to maintain the knowledge of dietary risk for nephrolithiasis. Participants also expressed a willingness to make requisite dietary changes if that information is provided. Given that most stone formers experience a recurrence, these findings highlight the need for more comprehensive patient education strategies on the modifiable risk factors for nephrolithiasis.

Papillary Ductal Plugging is a Mechanism for Early Stone Retention in Brushite Stone Disease.

PURPOSE: Mechanisms of early stone retention in the kidney are under studied and poorly understood. To date attachment via Randall's plaque is the only widely accepted theory in this regard, which is best described in idiopathic calcium oxalate stone formers. Brushite stone formers are known to have distinct papillary morphology relative to calcium oxalate stone formers. As such we sought to determine whether stone attachment mechanisms in such patients may be similarly unique. MATERIALS AND METHODS: Patients undergoing percutaneous and or ureteroscopic procedures for stone removal consented to endoscopic renal papillary examination and individual stone collection. Each removed stone was processed using micro computerized tomography to assess the 3-dimensional microstructure and the minerals contained, and search for common structural features indicative of novel mechanisms of early growth and attachment to renal tissue. RESULTS: A total of 25 intact brushite stones were removed from 8 patients and analyzed. Video confirmed attachment of 13 of the 25 stones with the remainder believed to have been accidently dislodged during the procedure. Microscopic examination by light and computerized tomography failed to show evidence of Randall's plaque associated with any stone containing brushite. Conversely each brushite stone demonstrated microstructural evidence of having grown attached to a ductal plug formed of apatite. CONCLUSIONS: Three-dimensional analysis of small brushite stones suggests overgrowth on ductal apatite plugs as a mechanism of early stone growth and retention. Such findings represent what is to our knowledge the initial supporting evidence for a novel mechanism of stone formation which has previously been hypothesized but never verified.

Investigational procedures in benign prostatic hypertrophy.

PURPOSE OF REVIEW: As benign prostatic hypertrophy (BPH) becomes a more common disease, there has been a dramatic rise in the number of investigational procedures being developed to manage it. We seek to present an overview of the most recently developed treatments and present clinical data related to application wherever available. RECENT FINDINGS: As a greater number of treatments become available for BPH, improved diagnostic testing could prove beneficial in helping guide patient selection. Efforts are underway to identify serum biomarkers associated with BPH as well as new classifications strategies, specifically with MRI, to determine both the anatomy of BPH as well as its histologic distribution. Outpatient-based procedures for BPH currently being developed include the temporary implantable nitinol device as well as intraprostatic injections such as Botox and PRX302. Aquablation is a novel technique that uses robotically guided high-pressured saline to ablate prostate tissue. Early data suggests noninferiority compared with TURP. Finally, efforts are underway to apply robotics to BPH with the advent of a robotic transurethral platform being designed for prostate enucleation. SUMMARY: Many new techniques are poised to be introduced to the BPH market over the coming years. The unique risk/benefit profiles as well as associated clinical outcomes of each will need to be studied in detail in order to help identify proper roles in the management of patients with symptomatic disease.

Patient-Reported Outcomes Measurement System (PROMIS®) for Patients with Urolithiasis: Initial Report.

PURPOSE: Health related quality of life is increasingly important in quality improvement efforts for medical conditions. However, it has proved challenging to measure health related quality of life for urolithiasis, given the distinct chronic and acute phases of this disease. We evaluated the use of PROMIS® (Patient-Reported Outcomes Measurement System) to assess the patient experience through acute stone episode stages. MATERIALS AND METHODS: PROMIS pain measures (intensity and interference) were obtained from patients at a subspecialty kidney stone clinic. Four types of clinical encounters were considered, including emergency department followup, trial of passage, stent removal and 1-month postoperative findings. Raw scores were translated into population normed T-scores with a T-score of 50 considered the reference population mean and a score of 60 considered 1 SD above the mean. T-scores were compared across encounter types on univariate and multivariate analysis. RESULTS: A total of 2,018 complete surveys were available from 1,162 patients. Mean pain intensity and pain interference T-scores differed significantly by encounter type (p <0.001). On multivariate analysis the OR of T-scores greater than 60 was higher for pain intensity and interference for all encounter types relative to postoperative findings, including emergency department followup 37.9 vs 124.9, passage trial 5.4 vs 10.5 and stent removal 9.4 vs 30.2 (p <0.001). Additionally, female gender and younger age were independent risk factors for T-scores greater than 60. CONCLUSIONS: PROMIS pain measures are responsive to the phase of care during symptomatic stone events. Further application of this instrument holds great potential as a valuable tool to improve the quality of urolithiasis care.

Outcomes of Holmium Laser Enucleation of the Prostate in the Re-Treatment Setting.

PURPOSE: Holmium laser enucleation of the prostate can also be applied in the re-treatment setting when other benign prostatic hyperplasia therapies fail. We compared outcomes in men who underwent holmium laser enucleation of the prostate in the primary vs the re-treatment setting. MATERIALS AND METHODS: We retrospectively reviewed the records of 2,242 patients who underwent holmium laser enucleation of the prostate at a total of 4 academic hospitals between 2003 and 2015. Patient demographics, and operative and perioperative outcomes were compared between re-treatment and primary holmium laser enucleation of the prostate. RESULTS: Of the 360 of 2,242 men (16%) who underwent re-treatment holmium laser enucleation of the prostate the procedure was done for residual urinary symptoms in 71%. The most common primary procedure was transurethral resection of the prostate in 42% of cases. Mean time between prior benign prostatic hyperplasia surgery and re-treatment was 68 months (range 1 to 444). There were no significant differences in age, prostate size, AUA (American Urological Association) symptom score or average flow rate between the cohorts. Perioperatively, re-treatment holmium laser enucleation of the prostate was associated with significantly shorter operative time, reduced blood loss, lower specimen weight and shorter length of stay. The AUA symptom score improved in both groups, although it remained higher in men who underwent re-treatment (6.5 vs 5.0, p <0.001). The likelihood of clot retention (4.7% vs 1.8%, p = 0.01) and urethral stricture (3.3% vs 1.5%, p = 0.043) was slightly higher in the re-treatment group. CONCLUSIONS: Immediate perioperative outcomes of holmium laser enucleation of the prostate performed in the re-treatment setting were no different from those in the primary setting. While re-treatment was associated with an increased likelihood of clot retention, urethral stricture and higher AUA symptom score, these minimal differences must be considered against the overall favorable symptom improvement across both cohorts.

Wolf Piranha Versus Lumenis VersaCut Prostate Morcellation Devices: A Prospective Randomized Trial.

PURPOSE: Holmium laser enucleation of the prostate for the management of benign prostatic hyperplasia involves the 2 steps of enucleation and morcellation. Few prostate morcellation devices are available. In this study we compare the Wolf Piranha and Lumenis® VersaCut™ prostate morcellation devices. MATERIALS AND METHODS: After institutional review board approval and patient informed consent, a prospective, randomized trial was initiated for patients with symptomatic benign prostatic hyperplasia undergoing holmium laser enucleation of the prostate. All procedures were performed by a single surgeon (JEL) at Indiana University Health Methodist Hospital using the Piranha or VersaCut prostate morcellation device. Patient demographics, and preoperative, intraoperative and postoperative data for patients in the 2 treatment groups were analyzed and compared in a prospective fashion. RESULTS: A total of 74 patients were enrolled and randomized for the treatment device. Both groups were comparable in terms of age, prostate specific antigen and prostate size. There was no difference in patient demographic and preoperative characteristics. The Piranha achieved a slightly higher morcellation rate at 5.6 gm per minute (range 1.4 to 18), compared to the VersaCut at 4.8 gm per minute (range 1.3 to 9.5). However, the difference was not statistically significant (p = 0.14). Cost analysis (USD per patient) favored the VersaCut ($241 vs $471, p <0.001). CONCLUSIONS: Morcellation rates for the Piranha and VersaCut prostate morcellation devices are comparable, with the Piranha having a statistically significant increased cost. The Wolf Piranha also has a more complicated design, making it less user-friendly for the operating room staff and, therefore, more difficult to troubleshoot than the Lumenis VersaCut. Nevertheless, 75% of urology faculty, fellows and residents preferred the Piranha over the VersaCut, reporting that when working properly, it was more efficient in tissue removal.

Salvage Percutaneous Nephrolithotomy: Analysis of Outcomes following Initial Treatment Failure.

PURPOSE: Percutaneous nephrolithotomy has high potential for morbidity or failure. There are limited data regarding risk factors for failure and to our knowledge no published reports of surgical outcomes in patients with prior failed attempts at percutaneous stone removal. MATERIALS AND METHODS: We identified patients referred to 3 medical centers after prior failed attempts at percutaneous nephrolithotomy. A retrospective chart review was performed to analyze reasons for initial failure and outcomes of salvage percutaneous nephrolithotomy. Outcomes were compared to those in a prospectively maintained database of more than 1,200 patients treated with a primary procedure. RESULTS: Salvage percutaneous nephrolithotomy was performed in 31 patients. Unsuitable access to the stone was the reason for failure in 80% of cases. Other reasons included infection, bleeding and inadequate instrument availability in 6.5% of cases each. Compared to patients who underwent primary percutaneous nephrolithotomy those treated with salvage were more likely to have staghorn calculi (61.3% vs 31.4%, p <0.01) and a larger maximum stone diameter (3.7 vs 2.5 cm, p <0.01), and require a secondary procedure (65.5% vs 42.1%, p <0.01). There was no significant difference between the cohorts in the remaining demographics or perioperative outcomes. All patients were deemed completely stone free except one who elected observation for a 3 mm nonobstructing fragment. CONCLUSIONS: Despite the more challenging nature and prior unsuccessful attempts at treatment, the outcomes of salvage percutaneous nephrolithotomy were no different from those of primary percutaneous nephrolithotomy when performed by experienced surgeons.

Institutional characteristics associated with receipt of emergency care for obstructive pyelonephritis at community hospitals.

PURPOSE: Delivering the recommended care is an important quality measure that has been insufficiently studied in urology. Obstructive pyelonephritis is a suitable case study for this focus because many patients do not receive such care, although guidelines advocate decompression. We determined the influence of hospital factors, particularly familiarity with urolithiasis, on the likelihood of decompression in such patients. MATERIALS AND METHODS: We used the NIS from 2002 to 2011 to retrospectively identify patients admitted to community hospitals with severe infection and ureteral calculi. Hospital familiarity with nephrolithiasis was estimated by calculating hospital stone volume (divided into quartiles) and hospital treatment intensity (the decompression rate in patients with ureteral calculi and no infection). After calculating national estimates we performed logistic regression to determine the association between the receipt of decompression and hospital stone volume, controlling for treatment intensity and other covariates thought to be associated with receiving recommended care. RESULTS: Of an estimated 107,848 patients with obstructive pyelonephritis 27.4% failed to undergo decompression. Discrepancies were greatest between hospitals with the highest and lowest stone volumes (76% vs 25%, OR 2.77, 95% CI 1.94-3.96, p <0.01) as well as high and low treatment intensity (78% vs 37%, p <0.01). CONCLUSIONS: High hospital stone volume and treatment intensity were associated with an increased likelihood of receiving decompression. Such findings might be useful to identify hospitals and regions where access to quality urological care should be augmented.

Nephrocalcinosis in Calcium Stone Formers Who Do Not have Systemic Disease.

PURPOSE: Nephrocalcinosis is commonly present in primary hyperparathyroidism, distal renal tubular acidosis and medullary sponge kidney disease. To our knowledge it has not been studied in patients with calcium phosphate stones who do not have systemic disease. MATERIALS AND METHODS: We studied patients undergoing percutaneous nephrolithotomy who had calcium phosphate or calcium oxalate stones and did not have hyperparathyroidism, distal renal tubular acidosis or medullary sponge kidney disease. On postoperative day 1 all patients underwent noncontrast computerized tomography. If there were no residual calcifications, the patient was categorized as not having nephrocalcinosis. If there were residual calcifications, the patient underwent secondary percutaneous nephrolithotomy. If the calcifications were found to be stones, the patient was categorized as not having nephrocalcinosis. If the calcifications were not stones, the patient was categorized as having nephrocalcinosis. Patients were grouped based on the type of stones that formed, including hydroxyapatite, brushite and idiopathic calcium oxalate. The extent of nephrocalcinosis was quantified as 0--absent nephrocalcinosis to 3--extensive nephrocalcinosis. Patients with residual calcifications on postoperative day 1 noncontrast computerized tomography who did not undergo secondary percutaneous nephrolithotomy were excluded from analysis. The presence or absence of nephrocalcinosis was correlated with metabolic studies. RESULTS: A total of 67 patients were studied, including 14 with hydroxyapatite, 19 with brushite and 34 with idiopathic calcium oxalate calculi. Nephrocalcinosis was present in 10 of 14 (71.4%), 11 of 19 (57.9%) and 6 of 34 patients (17.6%) in the hydroxyapatite, brushite and idiopathic calcium oxalate groups, respectively (chi-square p = 0.01). The mean extent of nephrocalcinosis per group was 1.98, 1.32 and 0.18 for hydroxyapatite, brushite and idiopathic calcium oxalate, respectively (p ≤0.001). The presence of nephrocalcinosis positively correlated with urine calcium excretion (mean ± SD 287.39 ± 112.49 vs 223.68 ± 100.67 mg per day, p = 0.03). CONCLUSIONS: Patients without systemic disease who form hydroxyapatite and brushite stones commonly have coexistent nephrocalcinosis. Nephrocalcinosis can occur in calcium oxalate stone formers but the quantity and frequency of nephrocalcinosis in this group are dramatically less.

Surgical decompression is associated with decreased mortality in patients with sepsis and ureteral calculi.

PURPOSE: The combination of sepsis and ureteral calculus is a urological emergency. Traditional teaching advocates urgent decompression with nephrostomy tube or ureteral stent placement, although published outcomes validating this treatment are lacking. National practice patterns for such scenarios are currently undefined. Using a retrospective study design, we defined the surgical decompression rate in patients admitted to the hospital with severe infection and ureteral calculi. We determined whether a mortality benefit is associated with this intervention. MATERIALS AND METHODS: Patient demographics and hospital characteristics were extracted from the 2007 to 2009 Nationwide Inpatient Sample. We identified 1,712 patients with ureteral calculi and sepsis. Multivariate logistic regression was performed to determine the association between mortality and surgical decompression. RESULTS: Of the patients 78% underwent surgical decompression. Mortality was higher in those not treated with surgical decompression (19.2% vs 8.82%, p <0.001). Lack of surgical decompression was independently associated with an increased OR of mortality even when adjusting for patient demographics, comorbidities and geographic region of treatment (OR 2.6, 95% CI 1.9-3.7). CONCLUSIONS: Absent surgical decompression is associated with higher odds of mortality in patients with sepsis and ureteral calculi. Further research to determine predictors of surgical decompression is necessary to ensure that all patients have access to this life saving therapy.

Near-infrared fluorescence imaging to facilitate super-selective arterial clamping during zero-ischaemia robotic partial nephrectomy.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There is concern that warm ischaemia time during partial nephrectomy may have an adverse impact on postoperative renal function. As a result, there is increased interest in developing a safe and effective method for performing non-ischaemic partial nephrectomy. Several novel approaches have recently been described. We present our initial experience performing zero-ischaemia partial nephrectomy using near-infrared fluorescence imaging to facilitate super-selective arterial clamping. We report the operative and early postoperative outcomes from such cases as compared with a matched cohort of patients undergoing traditional partial nephrectomy with clamping of the main renal artery. We show that this technique is both safe and effective and may lead to improved renal preservation at short-term follow-up. OBJECTIVE: To describe a novel technique of eliminating renal ischaemia during robotic partial nephrectomy (RPN) using near-infrared fluorescence (NIRF) imaging. PATIENTS AND METHODS: Over an 8-month period (March 2011 to November 2011), 34 patients were considered for zero-ischaemia RPN using the da Vinci NIRF system. Targeted tertiary/higher-order tumour-specific branches were controlled with robotic bulldog(s) or neurosurgical aneurysm micro-bulldog(s). Indocyanine green dye was given, and NIRF imaging used to confirm super-selective ischaemia, defined as darkened tumour/peri-tumour area with green fluorescence of remaining kidney. Matched pair analysis was performed by matching each patient undergoing zero-ischaemia RPN (n = 27) to a previous conventional RPN (n = 27) performed by the same surgeon. RESULTS: Of 34 patients, 27 (79.4%) underwent successful zero-ischaemia RPN; seven (20.6%) required conversion to main renal artery clamping (ischaemia time <30 min) for the following reasons: persistent tumour fluorescence after clamping indicating inadequate tumoral devascularization (n = 5), and parenchymal bleeding during RPN (n = 2). Matched-pair analysis showed comparable outcomes between cohorts, except for longer operating time (256 vs 212 min, P = 0.02) and superior kidney function (reduction of estimated glomerular filtration rate (-1.8% vs -14.9%, P = 0.03) in the zero-ischaemia cohort. All surgical margins were negative. CONCLUSIONS: In this pilot study, we show that zero-ischaemia RPN with NIRF is a safe alternative to conventional RPN with main renal artery clamping. Eliminating global ischaemia may improve functional outcomes at short-term follow-up.

Predicting Septic Shock After Emergent Ureteral Stenting in Stone-Related Obstruction and Presumed Infections.

Introduction: Systemic inflammatory response syndrome (SIRS) criteria have long been used to predict septic shock. The sequential organ failure assessment and quick sequential organ failure assessment (qSOFA) scores have been suggested to be more accurate predictors. This study aims to compare SIRS and qSOFA for predicting of septic shock in the setting of retrograde ureteral stenting for obstructing stones and concomitant urinary tract infection. Methods: A retrospective review of records at two centers of consecutive patients was performed. Patients with unilateral ureteral obstruction by a stone who underwent ureteral stent placement and suspicion of urinary tract infection were identified. Primary endpoints were SIRS and qSOFA positive scores, intensive care unit admission, and vasopressor requirements. Results: A total of 187 patients were included. SIRS criteria were met in 103 patients (55.1%) and in 30 patients who experienced septic shock. qSOFA criteria were met for 24 patients (12.8%) and in 18 patients who experienced septic shock. Specificity for postoperative septic shock was significantly higher for qSOFA than for SIRS criteria (75 vs 29.1%, McNemar test p < 0.001). Both SIRS and qSOFA had significant areas under the curve (AUC), qSOFA had a fair AUC of 0.750, p = 0.001, whereas SIRS had a poor AUC of 0.659, p = 0.008. Univariate logistic regression of SIRS and qSOFA for septic shock showed: qSOFA (odds ratio [OR] 46 [0.25-228], p = 0.001) and SIRS (OR 2.29 [0.716-7.37], p = 0.162). Conclusion: Although SIRS offers higher sensitivity, qSOFA score may offer advantages over SIRS criteria in evaluation of risk for septic shock for patients who present with obstructing ureteral stone and urinary tract infection.