Tranexamic acid vs placebo and its impact on bleeding, transfusions and stone-free rates in percutaneous nephrolithotomy: a systematic review and meta-analysis.

Introduction: Percutaneous nephrolithotomy (PCNL) is the standard of care for the treatment of large renal stones. Bleeding-related complications remain a major concern when performing this procedure. Tranexamic acid (TXA) has recently been studied in both urologic and non-urologic procedures to reduce bleeding, transfusions and complications. Material and methods: In June 2021 a systematic review was conducted following PRISMA guidelines on randomized prospective studies comparing the effects of TXA on bleeding complications during PCNL. Data was analyzed using Review Manager 5.3. Results: Eight studies were included with a total 1,201 patients, of which 598 received TXA and 603 received placebo. TXA was associated with less bleeding (decreased change in hemoglobin) -0.79 Hb g/dl [-1.09, -0.65] p <.00001 and decreased transfusion rates (OR 0.31 [0.18, 0.52] p <0.0001). This was also associated with lower complication rates, both minor, major and overall, OR 0.59[0.41, .85] p = 0.005, OR 0.31 [0.17, 0.56] p = 0.0001 and OR 0.40 [0.29, 0.56] p <0.00001 respectively. TXA was also associated with improved stone-free rates as compared with placebo (OR 1.79 [1.23, 2.62] p = 0.003). TXA resulted in shorter operative times (11.51 minutes [-16.25, -6.77] p =.001) and length of stay (-0.74 days [-1.13 -0.34] p = 0.0006). Two pulmonary embolisms were registered in a single study in the TXA group. Conclusions: In this meta-analysis, the use of TXA during PCNL was associated with a statistically significant reduction in the following parameters when compared with placebo: change in hemoglobin, transfusion rates, complication rates, operative time, and length of stay. It was also associated with improvement in stone-free rates. These data should be considered by surgeons performing PCNL.

Single-port versus multiport robotic-assisted radical prostatectomy: A systematic review and meta-analysis on the da Vinci SP platform.

CONTEXT: Prostate cancer is the most common cancer in men; robotic prostatectomy has cemented itself as part of the standard of care. Since its approval by the Food and Drug Administration in 2018, the SP console's application has been increasingly studied and compared with the multiport (MP) robotic approach. METHODS: Following PRISMA guidelines and PROSPERO registration CRD42021228744, a systematic review was performed in April 2021 on single-port robotic-assisted radical prostatectomies (SP-RARPs) compared to MP. Outcomes of interest were operative time, bleeding, complications, analgesic use, and postoperative continence, and erectile function. Data were analyzed with Review Manager 5.3. RESULTS: Seven studies were included, of which six studies met the inclusion criteria for quantitative synthesis, totalling 1068 patients, out of which 324 underwent SP-RARP and 744 underwent MP-RARP. No differences were found in baseline characteristics such as age, body mass index, prostatic-specific antigen, or stage. No differences in blood loss-15.77 mL [-42.44, 10.89], p = 0.25, operative time 3.93 min [-4.12, 11.98], p = 0.34, or positive surgical margins, with an odds ratio (OR) of 0.78 [0.55, 1.10], p = 0.15-were found. Length of stay was significantly shorter in SP -0.94 days [-1.56, -0.33], p = 0.003, with no differences in complication rates, with an OR of 1.29 [0.78, 2.14], p = 0.32, continence rates, with an OR of 1.29 [0.90, 1.83], p = 0.16, erectile function, with an OR of 0.86 [0.52, 1.40], p = 0.54, or biochemical recurrence. Qualitative evidence suggests decreased opioid consumption. CONCLUSION: SP-RARPs are feasible alternatives to the traditional MP with possible benefits in pain management and length of stay. Future high-quality studies are needed to confirm these findings.

Comparative Study Assessing Postoperative Renal Loss Using Two Different Partial Nephrectomy Techniques: Off-Clamp versus Standard On-Clamp Surgery.

OBJECTIVES: To evaluate a case-matched study comparing postoperative renal function using two surgical techniques: an off-clamp partial nephrectomy (PN) with the aid of the Altrus® device and a standard on-clamp laparoscopic PN. MATERIAL AND METHODS: A total of 36 patients underwent PN. Eighteen had the off-clamp technique and 18 had the standard laparoscopic on-clamp PN. Demographic, clinical, radiological, and perioperative data were collected for analysis. An emphasis on renal function was made by analyzing both the perioperative and follow-up with estimated glomerular filtration rate and MAG3. RESULTS: The median values did not signifcantly differ for age, Charlson Comorbidity Index, and hospital stay in the off-clamp versus on-clamp PN [62.5 (interquartile range, IQR 11) vs. 60 (IQR 16) years, 4 (IQR 2) vs. 5 (IQR 2) and 5 (IQR 1) vs. 4 (IQR 2) days], respectively. The median diameter of the tumors was 33 (IQR 23) versus 41 (IQR 28) mm (p = 0.63), with median R.E.N.A.L. nephrometry scores of 7 (IQR 2) versus 7 (IQR 2) (p = 0.33). There was greater blood loss in the Altrus® (375 vs. 200 ml, p = 0.037). The clamp time in the on-clamp group was 30 (IQR 6) minutes (range 22-68 minutes) compared to 0 minutes in the off-clamp group. There was no difference in hemoglobin or creatinine levels between the groups. However, the on-clamp group had a significant loss in ipsilateral renal function on the MAG3 scan (49 vs. 42%, p = 0.0001), whereas the off-clamp group had no difference (48 vs. 46%, p = 0.72). CONCLUSIONS: The off-clamp method for PN is a feasible and safe option with better preservation of ipsilateral renal function when compared with on-clamp PN in the treatment of small renal masses.

Quality of life in patients with kidney stones: translation and validation of the Spanish Wisconsin Stone Quality of Life Questionnaire.

The Spanish version of the Wisconsin Stone Quality of Life (WISQOL) questionnaire was developed and validated. A double-back translation of the WISQOL was conducted and syntactic amendments were made, resulting in the Spanish version of the WISQOL (S-WISQOL) which then went through a readability analysis. Stone formers from two hospitals in Mexico (Merida and Monterrey) filled in the S-WISQOL and the Short Form 36 (SF36). Convergent validity was assessed by the correlation of both questionnaires. Internal consistency was evaluated by Cronbach's α, and external validity by comparing between centers. The impact of clinical settings on patients' health-related quality of life (HRQOL) scores was tested. Each hospital's institutional review board approved the project and informed consent was obtained from all participants. A total of 87 Spanish-speakers patients completed the S-WISQOL and SF36 and a good correlation was found between both (r = 0.75, p < 0.001). S-WISQOL readability was rated as "easy". Patients from Merida had longer median duration (years) with stones, more stone-related procedures, and hospitalizations, and scored lower on WISQOL (p = 0.006). Internal consistency was good as Cronbach's α coefficients ranged between acceptable and excellent. Stone-related admissions and duration of stones were inversely correlated with S-WISQOL score (- 0.254 and - 0.283, respectively; p < 0.005) but not to SF36. The S-WISQOL is an internally consistent, reliable, and valid instrument to assess HRQOL in Spanish-speaking patients with kidney stones. The S-WISQOL is generalizable as demonstrated by good external validity among centers. S-WISQOL scores can be added as an outcome for kidney stone treatments.

Spatial Clusters of Children with Cleft Lip and Palate and Their Association with Polluted Zones in the Monterrey Metropolitan Area.

This study examines the spatial structure of children with cleft lip and palate (CLP) and its association with polluted areas in the Monterrey Metropolitan Area (MMA). The Nearest Neighbor Index (NNI) and the Spatial Statistical Scan (SaTScan) determined that the CLP cases are agglomerated in spatial clusters distributed in different areas of the city, some of them grouping up to 12 cases of CLP in a radius of 1.2 km. The application of the interpolation by empirical Bayesian kriging (EBK) and the inverse distance weighted (IDW) method showed that 95% of the cases have a spatial interaction with values of particulate matter (PM10) of more than 50 points. The study also shows that 83% of the cases interacted with around 2000 annual tons of greenhouse gases. This study may contribute to other investigations applying techniques for the identification of environmental and genetic factors possibly associated with congenital malformations and for determining the influence of contaminating substances in the incidence of these diseases, particularly CLP.

A Population-Based Cohort Study of the Impact of Infectious Complications Requiring Hospitalization after Prostate Biopsy on Radical Prostatectomy Surgical Outcomes.

OBJECTIVE: To compare radical prostatectomy outcomes in men with and without exposure to a major infectious event within 30-days of a prior TRUS-biopsy. MATERIALS AND METHODS: This retrospective cohort study included men who underwent radical prostatectomy from 2002 to 2013 in Ontario, Canada. Several linked administrative databases were used. Exposure was defined as hospitalization with evidence of a urinary tract infection or sepsis during the first 30-days after a prostate biopsy. The primary outcome was a composite of procedures indicative of a likely serious complication of radical prostectomy within the first 12 months after surgery. Secondary outcomes included oncological, functional, and hospital related events within 2 years of radical prostatectomy. RESULTS: A total of 26,254 patients were included in this study and 530 (2.02%) had a post-TRUS-biopsy infection. A similar proportion of patients with and without a post-TRUS-biopsy infectious event experienced the composite primary outcome (1.7% vs 1.1%; odds ratio [OR] 1.61, 95% confidence interval [CI] 0.82-3.14; P = .16). However, exposed patients had significantly higher odds of perioperative blood transfusion (OR 1.61, 95% CI 1.30-2.00; P <.001), bladder neck contracture (OR 1.35, 95% CI 1.12-1.63; P = .002), and 30-day hospital readmission (OR 2.08, 95% CI 1.47-2.95; P <.001), and a small but significant increase in length of hospital stay (P = 0.005). No other significant differences were observed. CONCLUSION: Although prior infectious events are associated with increased risk of blood transfusion, bladder neck contracture, and hospital readmission following radical prostatectomy, results from this study suggest that major surgical complications, are not adversely affected by TRUS-biopsy related infections.

The Impact of Multiple Prostate Biopsies on Risk for Major Complications Following Radical Prostatectomy: A Population-based Cohort Study.

OBJECTIVE: To evaluate the impact of multiple transrectal ultrasound-guided prostate biopsies (TRUS-Bx) before radical prostatectomy (RP) on surgical outcomes. MATERIALS AND METHODS: Administrative databases were used to identify all patients who had a RP performed in the province of Ontario from April 1, 2002, to March 31, 2013. TRUS-Bx prior to RP were identified and patients were categorized as having one or more than one prior TRUS-Bx. The primary end point was a composite index of serious surgical complications. Secondary outcomes included oncological interventions, functional-related events, and general health service-related outcomes. RESULTS: Among 27,637 patients, 4780 (17.3%) had ≥2 biopsies performed before RP. The proportion of patients who experienced the composite end point was similar between those with one TRUS-Bx compared to those with ≥2 TRUS-Bx (1.05% vs 1.19%, OR 1.14, 95% CI 0.85-1.52). Patients with ≥2 biopsies were more likely to have a perioperative blood transfusion compared to patients with only 1 biopsy (15.5% vs 12.8%, OR 1.25, 95% CI 1.15-1.37), while readmission rate and 30-day mortality were similar. The need for radiotherapy and androgen deprivation therapy within the first year after RP was higher in patients with a single biopsy. Patients with multiple TRUS-Bx were more likely to require post-RP urodynamic evaluation and bladder neck contracture-related interventions but were not at increased odds of surgery for incontinence or erectile dysfunction. CONCLUSION: Perioperative outcomes after RP are similar between men with single or multiple TRUS-Bx, although multiple TRUS-Bx were associated with an increased odds of perioperative blood transfusion.

A novel approach to off-clamp partial nephrectomy demonstrates significant improvements in renal injury in an experimental porcine model.

INTRODUCTION: We sought to design a partial nephrectomy (PN) with contralateral total nephrectomy porcine model and assess the underlying mechanisms of ischemia reperfusion injury (IRI) after PN using a novel, clinically approved resection device. METHODS: Domestic male pigs (n=9) underwent left lower pole PN, allocated to either standard (Group 1) or no ischemia PN (Group 2), followed by contralateral nephrectomy. Biochemical studies were performed at baseline, Day 2, and Day 7; after sacrifice, kidneys were processed for histological analysis. Apoptotic markers were measured by Western blot analyses. Urinary biomarkers were measured to assess acute kidney injury. RESULTS: At Day 2 following PN, there was a significant rise in serum creatinine in Group 1 compared to Group 2 (355 vs. 136 mmol/L; p=0.008). Intra-renal tissue oxygen saturation after PN was inversely correlated with postoperative creatinine (rs -0.75; p=0.012) and the grade of acute tubular necrosis (rs -0.70; p=0.036). We observed a rise in expression of pro-apoptotic markers and pro-inflammatory markers in Group 1 following PN compared to Group 2. Histological analysis revealed higher grade of apoptosis in Group 1. CONCLUSIONS: IRI associated with standard PN has a deleterious impact on acute renal function, markers of tissue injury, and histological parameters, compared to off-clamp PN using the ALTRUS device. We identified several intraoperative and postoperative markers that may be used as predictors for functional and histological injury following PN.

KIM-1 Is a Potential Urinary Biomarker of Obstruction: Results from a Prospective Cohort Study.

INTRODUCTION: Partial or complete obstruction of the urinary tract is a common and challenging urological condition that may occur in patients of any age. Serum creatinine is the most commonly used method to evaluate global renal function, although it has low sensitivity for early changes in the glomerular filtration rate or unilateral renal pathology. Hence, finding another measurable parameter that reflects the adaptation of the renal physiology to these circumstances is important. Several recent studies have assessed the use of new biomarkers of acute kidney injury (AKI), but the information among patients with stone disease and those with obstructive uropathy is limited. MATERIAL AND METHODS: A prospective cohort study was conducted to determine the urinary levels of kidney injury molecule-1 (KIM-1), Total and Monomeric neutrophil gelatinase-associated lipocalin (NGAL) in patients with hydronephrosis secondary to renal stone disease, congenital ureteropelvic junction obstruction or ureteral stricture. Comparison between patients with hydronephrosis and no hydronephrosis was carried out along with correlation analysis to detect factors associated with biomarker expression. RESULTS: Urinary levels of KIM-1 significantly decreased after hydronephrosis treatment in patients with unilateral obstruction (1.19 ng/mL vs 0.76 ng/mL creatinine, p = 0.002), additionally KIM-1 was significantly higher in patients with hydronephrosis compared to stone disease patients without radiological evidence of obstruction (1.19 vs 0.64, p = 0.006). Total and Monomeric NGAL showed a moderate correlation with the presence of leukocyturia. We found that a KIM-1 value of 0.735 ng/mg creatinine had a sensitivity of 75% and specificity of 67% to predict the presence of hydronephrosis in preoperative studies (95% CI 0.58-0.87, p = 0.006). CONCLUSION: Our results show that KIM-1 is a promising biomarker of subclinical AKI associated with hydronephrosis in urological patients. NGAL values were influenced by the presence of leukocyturia, limiting its usefulness in this population.

Natural History of Residual Fragments After Percutaneous Nephrolithotomy: Evaluation of Factors Related to Clinical Events and Intervention.

OBJECTIVE: To determine the natural history of residual fragments (RF) after percutaneous nephrolithotomy in long-term patient follow-up and to identify possible predictive factors for future intervention. MATERIALS AND METHODS: We assessed all patients from 2006 to 2013 with postoperative computed tomography scan revealing RF, who did not undergo second-look nephroscopy or immediate ancillary procedures, and with at least 12 months of clinical follow-up. We evaluated factors associated with clinical, radiological, and surgical outcomes. Kaplan-Meier curves were used to calculate the proportion of asymptomatic and treatment-free patients during follow-up. RESULTS: From 781 percutaneous nephrolithotomies performed, 202 patients underwent postoperative computed tomography scan and 44 patients with residual stones were included in the analysis. Mean follow-up was 57.9 months. A total of 24 patients (54.5%) developed at least 1 clinical outcome, and 32 (72.7%) patients had a surgical intervention. Only 4 patients had radiological evidence of stone passage. Multivariate analysis found that RF >4 mm and struvite or apatite stones were significant predictors for surgical intervention. The 5-year estimated probability to remain intervention free was 29%. CONCLUSION: Despite the size of the RF, the vast majority of patients required an intervention during long-term follow-up. We identified that RFs of diameter >4 mm associate with the need for a surgical therapy, but the rate of clinical events was not affected by the size or location of the stones. Struvite or apatite composition stones had an increased risk of intervention during follow-up. Spontaneous passage was an uncommon event in this cohort.

Assessing the Magnitude of Effect of Bone Structures on Shockwave Lithotripsy Fragmentation: Results from an In Vitro Study.

INTRODUCTION: Several anatomic and clinical factors have been implicated in the failure rates of shock wave lithotripsy (SWL), including the attenuating effects of bony structures. We designed an in vitro model that incorporates the lumbar spine, including vertebral bodies and transverse processes along the pathway of shockwaves, to mimic the clinical scenario during SWL of upper ureteral stones. We hypothesized that the presence of bone structures in the SWL pathway significantly affects the fragmentation rate. MATERIALS AND METHODS: An ordnance gelatin (OG) model was conceptualized and created to allow a pig's lumbar spine to be embedded within it. Artificial urinary calculi weighing 2 ± 0.1 g (1.2-cm diameter) were prepared using BegoStone plaster. The trial was divided into two arms: group 1 models had OG only and served as the control and group 2 models had the bone embedded in the gelatin with stone wells placed above the transverse processes. Twenty-four stones per group were subjected to SWL using the STORZ MODULITH SLX-F2 lithotripter, using the same treatment parameters. Fragments were sieved through 2- and 4-mm filters, and the fragmentation coefficients (FC) were calculated. The Mann-Whitney test was used to compare FC between the two groups. RESULTS: The mean fragmentation rate of group 1 was statistically significantly higher compared with group 2 using a 4-mm sieve (43% vs 0.62%, p < 0.001) and the 2-mm filter (18% vs 0.52%, p < 0.001). CONCLUSIONS: The presence of bone structures dramatically reduces the fragmentation rate of phantom stones using an OG in vitro model. The OG model is inexpensive and simple to use to simulate clinical situations during SWL.

Multicenter External Validation and Comparison of Stone Scoring Systems in Predicting Outcomes After Percutaneous Nephrolithotomy.

BACKGROUND AND PURPOSE: Several scoring systems have recently emerged to predict stone-free rate (SFR) and complications after percutaneous nephrolithotomy (PCNL). We aimed to compare the most commonly used scoring systems (Guy's stone score, S.T.O.N.E. nephrolithometry, and CROES nomogram), assess their predictive accuracy for SFR and other postoperative variables, and develop a risk group stratification based on these scoring systems. MATERIALS AND METHODS: We performed a retrospective review of patients who have had a PCNL at four academic institutions between 2006 and 2013. Primary outcome was SFR within 3 weeks of the surgery and secondary outcomes were operative time (OT), complications, and length of stay (LOS). We performed chi-squared, t-test, logistic, linear, and Poisson regressions, as well as receiver operating characteristics curve with area under the curve (AUC) calculation. RESULTS: We identified 586 patients eligible for analysis. Of these, 67.4% were stone free. Guy's, S.T.O.N.E., and CROES score were predictive of SFR on multivariable logistic regression (odds ratio [OR]: 1.398, 95% confidence interval [CI]: 1.056, 1.852, p = 0.019; OR: 1.417, 85% CI: 1.231, 1.631, p < 0.001; OR: 0.993, 95% CI: 0.988, 0.998, p = 0.004) and have similar predictive accuracy with AUCs of 0.629, 0.671, and 0.646, respectively. On multivariable linear regression, only S.T.O.N.E. was an independent predictor of longer OT (ß = 14.556, 95% CI: 12.453, 16.660, p < 0.001). None of the scores were independent predictors of postoperative complications or a longer LOS. Poisson regression allowed for risk group stratification and showed the S.T.O.N.E. score and CROES nomogram to have the most distinct risk groups. CONCLUSIONS: The three evaluated scoring systems have similar predictive accuracy of SFR. S.T.O.N.E. has additional value in predicting OT. Risk group stratification can be used for patient counseling. Further research is needed to identify whether or not any is superior to the others with regard to clinical usefulness and predictive accuracy.

Novel Methods of Determining Urinary Calculi Composition: Petrographic Thin Sectioning of Calculi and Nanoscale Flow Cytometry Urinalysis.

Accurate determination of urinary stone composition has significant bearing on understanding pathophysiology, choosing treatment modalities and preventing recurrence. A need exists for improved methods to determine stone composition. Urine of 31 patients with known renal calculi was examined with nanoscale flow cytometry and the calculi collected during surgery subsequently underwent petrographic thin sectioning with polarized and fluorescent microscopy. Fluorescently labeled bisphosphonate probes (Alendronate-fluorescein/Alendronate-Cy5) were developed for nanoscale flow cytometry to enumerate nanocrystals that bound the fluorescent probes. Petrographic sections of stones were also imaged by fluorescent and polarized light microscopy with composition analysis correlated to alendronate +ve nanocrystal counts in corresponding urine samples. Urine samples from patients with Ca(2+) and Mg(2+) based calculi exhibited the highest alendronate +ve nanocrystal counts, ranging from 100-1000 nm in diameter. This novel urine based assay was in agreement with composition determined by petrographic thin sections with Alendronate probes. In some cases, high alendronate +ve nanocrystal counts indicated a Ca(2+) or Mg(2+) composition, as confirmed by petrographic analysis, overturning initial spectrophotometric diagnosis of stone composition. The combination of nanoscale flow cytometry and petrographic thin sections offer an alternative means for determining stone composition. Nanoscale flow cytometry of alendronate +ve nanocrystals alone may provide a high-throughput means of evaluating stone burden.

The Effect of Renal Cysts on the Fragmentation of Renal Stones During Shockwave Lithotripsy: A Comparative In Vitro Study.

PURPOSE: To assess the potential effect of simple renal cysts (SRC) on stone fragmentation during shockwave lithotripsy (SWL) in an in vitro model. MATERIALS AND METHODS: The in vitro model was constructed using 10% ordnance gelatin (OG). Models were created to mimic four scenarios: Model A-with an air-filled cavity (suboptimal for stone fragmentation); model B-without a cavity (normal anatomy); model C-with a 3-cm serum filled cavity (to represent a small SRC); model D-with a 4-cm serum filled cavity (to represent a larger SRC). SWL was applied to 24 standardized phantom stones (weight of 2±0.1 g) in each model using a standardized protocol. Stone fragments were retrieved, then dried overnight at room air temperature. Fragmentation coefficient (FC) was calculated for each stone, for fragments<4 mm and <2 mm. RESULTS: The OG in vitro model was robust enough for the proposed research. There was no fragmentation evident in model A as expected. The mean FC was 29.7 (±20.5) and 39.7 (±23.7) for <4 mm fragments (P=0.069) and 7.6 (±4.1) and 10.6 (±6.7) for <2 mm fragments (P=0.047), for noncystic and cystic models, respectively. The mean FC was 29.7 (±20.5), 38.8 (±26.2) and 40.7 (±21.3) for <4 mm fragments (P=0.213) and 7.6 (±4.1), 11.1 (±8) and 10.2 (±5.3) for <2 mm fragments (P=0.138), for models B, C, and D, respectively. CONCLUSION: Our in vitro experiment confirms better stone fragmentation associated with SWL in the presence of adjacent SRC.

Combining Mean and Standard Deviation of Hounsfield Unit Measurements from Preoperative CT Allows More Accurate Prediction of Urinary Stone Composition Than Mean Hounsfield Units Alone.

INTRODUCTION AND OBJECTIVES: The mineral composition of a urinary stone may influence its surgical and medical treatment. Previous attempts at identifying stone composition based on mean Hounsfield Units (HUm) have had varied success. We aimed to evaluate the additional use of standard deviation of HU (HUsd) to more accurately predict stone composition. METHODS: We identified patients from two centers who had undergone urinary stone treatment between 2006 and 2013 and had mineral stone analysis and a computed tomography (CT) available. HUm and HUsd of the stones were compared with ANOVA. Receiver operative characteristic analysis with area under the curve (AUC), Youden index, and likelihood ratio calculations were performed. RESULTS: Data were available for 466 patients. The major components were calcium oxalate monohydrate (COM), uric acid, hydroxyapatite, struvite, brushite, cystine, and CO dihydrate (COD) in 41.4%, 19.3%, 12.4%, 7.5%, 5.8%, 5.4%, and 4.7% of patients, respectively. The HUm of UA and Br was significantly lower and higher than the HUm of any other stone type, respectively. HUm and HUsd were most accurate in predicting uric acid with an AUC of 0.969 and 0.851, respectively. The combined use of HUm and HUsd resulted in increased positive predictive value and higher likelihood ratios for identifying a stone's mineral composition for all stone types but COM. CONCLUSIONS: To the best of our knowledge, this is the first report of CT data aiding in the prediction of brushite stone composition. Both HUm and HUsd can help predict stone composition and their combined use results in higher likelihood ratios influencing probability.

The correlation between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED): results from a survey in males from Mexico City (MexiLUTS).

INTRODUCTION: ED and LUTS affect a high proportion of male population. Although Hispanics are suspected to have a higher risk of experiencing LUTS, detailed information on its frequency and association with ED in this population is scarce. OBJECTIVE: To determine the frequency of LUTS and ED, and its correlation in Mexican males. METHODS: A cross-sectional analytical survey was answered by 1041 men. It included the International Prostate Symptom Score and the quality of life question (IPSS/QoL); International Index of Erectile Function (IIEF-5); the short form of the International Consultation of Incontinence Questionnaire (ICIQ-SF); and demographic data. For the analysis, we divided our population into 2 groups (18-39 and 40 and older), and then an exploratory correlation analysis was performed to search for significant differences among IPSS severity groups, and finally a multivariate regression model was applied. RESULTS: Mean age was 48.6 ± 14.5 years. One hundred twenty-three individuals (11.8 %) were asymptomatic, and 611 (58.7 %) had mild, 226 (21.7 %) had moderate, and 81 (7.8 %) had severe IPSS score. The most common symptoms were nocturia (72.4 %), increased urinary frequency (58.3 %), and slow urinary stream (42.6 %). Two hundred fifty-eight (24.7 %) complained of incontinence. Of 765 individuals, 484(63.2 %) reported some degree of ED. Severe LUTS, DM, and age were independent risk factors for ED severity. CONCLUSION: LUTS and ED may represent one of the largest sources of morbidity in our population, and their association was demonstrated. Awareness on these entities should be raised, and further research is required to determine the higher frequency of LUTS and ED in Hispanics.

Risk Factors for Postoperative Complications of Percutaneous Nephrolithotomy at a Tertiary Referral Center.

PURPOSE: We sought to describe and evaluate the complications related to percutaneous nephrolithotomy and identify risk factors of morbidity according to the modified Clavien scoring system. We also sought to specify which perioperative factors are associated with minor and major complications. MATERIALS AND METHODS: We retrospectively analyzed data on patients who underwent percutaneous nephrolithotomy from 1990 to 2013. Descriptive statistics were used to analyze patient characteristics, medical comorbidities and perioperative features. Complications were categorized according to the Clavien score for percutaneous nephrolithotomy. The Mann-Whitney and Fisher exact tests were used as appropriate. Logistic regression analysis was performed to look for prognostic factors associated with major complications. RESULTS: A total of 2,318 surgeries were evaluated. Mean age of the population was 53.7 years. The stone-free rate at hospital discharge was 81.6%. The overall complication rate was 18.3%. Two deaths occurred. Patients with any postoperative complications were older, had more comorbidities, were more likely to have staghorn calculi and had longer operative time and hospital stay on univariate analysis (p<0.05). Age 55 years or older and upper pole access were independent predictors of major complications on multivariate analysis. Other factors such as a history of urinary tract infections, body mass index, stone composition, previous percutaneous nephrolithotomy and multiple tracts were not associated with a major complication. CONCLUSIONS: At our center percutaneous nephrolithotomy is an excellent option for complex kidney stone management with a low overall complication rate. Older patient age and upper pole access are significantly associated with an increased risk of a major complication.