Thulium Fiber Laser Versus Holmium:Yttrium Aluminum Garnet for Lithotripsy: A Systematic Review and Meta-analysis.

CONTEXT: Thulium fiber laser (TFL) emerged as a competitor of holmium:yttrium aluminum garnet (Ho:YAG) laser for the treatment of urinary stones. OBJECTIVE: To compare the efficacy between Ho:YAG and TFL for laser lithotripsy of renal and ureteral stones. EVIDENCE ACQUISITION: A literature search was conducted using PubMed/Medline, Embase, and Web of Science databases to identify reports published until May 2023. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed to identify eligible studies. The primary outcome was to compare the stone-free rate (SFR) between Ho:YAG and TFL for laser lithotripsy. EVIDENCE SYNTHESIS: Eleven studies met our inclusion criteria, and data from 1286 and 880 patients who underwent, respectively, Ho:YAG and TFL laser lithotripsy were reviewed. Most studies included ureteroscopy (URS) and retrograde intrarenal surgeries as procedures, two included percutaneous nephrolithotomy, and one included URS exclusively. Only two studies reported results in pediatric patients. TFL was associated with a higher SFR (odds ratio [OR] 1.84, 95% confidence interval [CI]: 1.06-3.20; p = 0.031) when no residual fragment is considered, but not when SFR refers to the presence of fragments <3 mm (OR 2.48, 95% CI: 0.98-6.29; p = 0.055) or when only Ho:YAG with MOSES is considered (p = 0.068). According to the stones' location, TFL was associated with higher SFRs than Ho:YAG for renal (OR 3.14, 95% CI: 1.69-5.86; p < 0.001) but not for ureteral (p = 0.8) stones. TFL was associated with a lower intraoperative complication rate (OR 0.34, 95% CI: 0.19-0.63; p < 0.001). No difference was found in major (p = 0.4) or overall (p = 0.4) complication rate, operative time (p = 0.051), and laser time (p = 0.9). CONCLUSIONS: TFL is a promising laser for the treatment of urinary stones with some advantages over Ho:YAG. Further high-quality studies are needed to confirm these findings and optimize the surgical settings. PATIENT SUMMARY: The use of thulium fiber laser rather than holmium:yttrium aluminum garnet permits to reach a higher stone-free rate in stones located in the kidney rather than in the ureter.

Role, Cost, and Availably of Urinary pH Monitoring for Kidney Stone Disease-A Systematic Review of the Literature.

PURPOSE OF REVIEW: Urinary pH is an important factor related to renal stone disease, and it plays an essential role in stone prevention. Monitoring of urinary pH by patients at home provides information that can help to assess the treatment needed by each patient. We conducted a systematic review is to assess the available evidence concerning urinary pH monitoring methods along with their accuracy, cost, and usefulness by patients with urolithiasis. RECENT FINDINGS: A total of 9 articles were included (1886 urinary pH measurements). They reported information about urinary dipsticks, portable electronic pH meters and electronic strip readers, amongst other methods. Accuracy was compared with a laboratory pH meter (gold standard). Urinary dipsticks were found to be not accurate enough to guide clinical decision making and portable electronic pH meters showed promising results. Urinary dipsticks are neither precise nor accurate enough. Portable electronic pH meters seem to be more accurate, easy to use, and cost-effective. They are a reliable source for patients to use at home in order to prevent future episodes of nephrolithiasis.

Estimated Radiation Dose to the Lens During Endourologic Procedures: The Role of Leaded Glasses and the ALARA Protocol-An ESU/ESUT-YAU Endourology Group Collaboration.

Purpose: On February 6, 2018, the European Atomic Energy Community reduced the annual equivalent dose limit for the lens from 150 to 20 mSv/year, because of its association with cataracts at low radiation doses. Our aim was to estimate the radiation doses received by the lens during endourologic procedures that require fluoroscopy. Materials and Methods: Multicenter study including prospective data of annual eye dosimeters between 2017 and 2020. Four endourologists used an eye dosimeter in endourologic procedures that require fluoroscopy (ureteroscopy, retrograde intrarenal surgery, and percutaneous nephrolithotomy). Surgeons 1 and 2 wore leaded glasses; surgeon 1 also used the as low as reasonably achievable (ALARA) protocol. Descriptive statistical analysis using SPSS 25.0 was conducted. Results: Surgeons 1, 2, 3, and 4 performed a median of 159, 586, 102, and 129 endourologic procedures per year, respectively, for a total of 641, 2340, 413, and 350 procedures between 2017 and 2020. The median annual dose of lens radiation exposure was 0.16, 1.18, 3.79, and 1.42 mSv per year, respectively, which corresponds to 0.001, 0.009, 0.024, and 0.012 mSv per procedure. The two surgeons who used leaded glasses registered a lower radiation dose per procedure (0.001 vs 0.027). Similarly, the urologist who used the ALARA protocol registered the lowest lens radiation dose compared with the three surgeons who did not use it (0.001 vs 0.023). Conclusions: The endourologists who participated in this study effectively comply with current guidelines on radiation exposure to the lens. Registered eye lens radiation does not seem to be related to the number of procedures but rather to the use of leaded glasses and the ALARA protocol.

Use of Moses 2.0 with extended frequency and optimized Moses vs. high-power laser in MiniPCNL: a randomized controlled trial.

The aim of the study was to compare standard high-power laser (with < 80 Hz) to extended frequency (> 100 Hz) lithotripsy during miniPCNL. 40 patients were randomized in to two groups undergoing MiniPCNL. For both groups, the Holmium Pulse laser Moses 2.0 (Lumenis) was used. For group A, standard high-power laser with < 80 Hz, with Moses distance was set using up to 3 J. For Group B, extended frequency (100-120 Hz) was used allowing up to 0.6 J. All patients underwent MiniPCNL using an 18 Fr balloon access. Demographics were comparable between groups. Mean stone diameter was 19 mm (14-23) with no differences between groups (p = 0.14). Mean operative time was 91 and 87 min for group A and B (p = 0.71), mean laser time was similar in both groups, 6.5 min and 7.5 min, respectively (p = 0.52) as well as the number of laser activations during the surgery (p = 0.43). Mean Watts used was 18 and 16 respectively being similar in both groups (p = 0.54) as well as the total KJoules (p = 0.29). Endoscopic vision was good in all surgeries. The endoscopic and radiologic stone free rate was achieved in all patients expect for two in both groups (p = 0.72). Two Clavien I complications were seen, a small bleeding for group A and a small pelvic perforation in group B. The use of high-power holmium laser with extended frequency and optimized Moses was effective and safe being comparable to standard high-power laser for MiniPCNL allowing more versatility with the setting range.

Lasers for stone lithotripsy: advantages/disadvantages of each laser source.

PURPOSE: The purpose of this article was to make a narrative review of the literature in search of all articles regarding thulium:yttrium-aluminium-garnet (YAG), thulium laser fiber (TFL) and holmium:YAG (Ho:YAG) for lithotripsy from 2020 to 2023. A selection of articles of special interest and best evidence was made in order to give a better perspective on their advantages and disadvantages. RECENT FINDINGS: New Ho:YAG technologies of as high power, high frequency and pulsed modulations have shown promising results for lithotripsy by reducing retropulsion with good ablation efficiency. High peak power makes it particularly good for percutaneous nephrolithotomy. High intrarenal temperatures and correct setting are still concerning points.TFL has arrived to be one of the main players in flexible ureteroscopy. Being highly efficient and quick, and by producing micro-dusting the laser is quickly heading to become a gold standard. The new pulsed Thulium YAG is the newest laser. For now, only in-vitro studies show promising results with efficient lithotripsy. As the peak power lies between Ho:YAG and TFL it may be able to adequately perform when needing and low power lithotripsy. SUMMARY: Several new technologies have been developed in the last years for stone lithotripsy. All being efficient and safe if well used. Different advantages and disadvantages of each laser must be taken into consideration to give each laser the proper indication.

Bowel Perforation after Extracorporeal Wave Lithotripsy: A Review of the Literature.

INTRODUCTION: Extracorporeal wave lithotripsy (ESWL) is considered a first-line treatment for renal and ureteral stones up to 10-20 mm in diameter. Complications are uncommon, with a reported rate of 0-6% in the literature. Bowel perforation has only been described in a few case reports but requires rapid diagnosis and treatment. METHODS: A review of the literature from PubMed/Medline, Embase, Cochrane, and Web of Science databases was performed including studies reporting bowel perforation secondary to ESWL between January 1990 and June 2022. RESULTS: We found 16 case reports of intestinal perforation in the literature. Although some patients had previously undergone abdominal surgery or had inflammatory intestinal disease, others were without comorbidities that could lead to complications. Abdominal pain was the main symptom and imaging was required to confirm the diagnosis, which usually necessitated a surgical intervention. As regards the ESWL technique, it appears that the combination of a high energy level and the prone position constitutes a risk factor for these rare complications. At the authors' centre, only one case has been reported among 24,000 ESWL procedures over 20 years: A 59-year-old female who underwent ESWL for a distal right ureteral stone presented acute abdominal pain and free intraperitoneal pelvic fluid on ultrasound. A CT scan revealed a small bowel perforation requiring open laparotomy with primary closure. CONCLUSIONS: In conclusion, although bowel perforation after ESWL is rare, progressive abdominal pain with tenderness at physical examination requires proper imaging evaluation to exclude bowel perforation and prompt intervention if required.

New Generation Pulse Modulation in Holmium:YAG Lasers: A Systematic Review of the Literature and Meta-Analysis.

(1) Background: New pulse modulation (PM) technologies in Holmium:YAG lasers are available for urinary stone treatment, but little is known about them. We aim to systematically evaluate the published evidence in terms of their lithotripsy performance. (2) Methods: A systematic electronic search was performed (MEDLINE, Scopus, and Cochrane databases). We included all relevant publications, including randomized controlled trials, non-randomized comparative and non-comparative studies, and in-vitro studies investigating Holmium:YAG lithotripsy performance employing any new PM. (3) Results: Initial search yielded 203 studies; 24 studies were included after selection: 15 in-vitro, 9 in-vivo. 10 In-vitro compared Moses with regular PM, 1 compared Quanta's, 1 Dornier MedTech's, 2 Moses with super Thulium Fiber Laser, and 1 compared Moses with Quanta PMs. Six out of seven comparative studies found a statistically significant difference in favor of new-generation PM technologies in terms of operative time and five out of six in fragmentation time; two studies evaluated retropulsion, both in favor of new-generation PM. There were no statistically significant differences regarding stone-free rate, lasing and operative time, and complications between Moses and regular PM when data were meta-analyzed. (4) Conclusions: Moses PM seems to have better lithotripsy performance than regular modes in in-vitro studies, but there are still some doubts about its in-vivo results. Little is known about the other PMs. Although some results favor Quanta PMs, further studies are needed.

Importancia del pH urinario en la urolitiasis / Urinary pH relevance on urolithiasis management

OBJETIVO: El pH urinario es un factor que influye en la litogénesis urinaria de forma importante. Puede condicionar la nucleación heterogénea del oxalato de calcio y la cristalización o disolución de otras sustancias como el ácido úrico, cistina y fosfatos. Su medición exacta y precisa es una herramienta para orientar el tratamiento y la prevención. La forma más precisa de medirlo es la utilización de un electrodo de vidrio y un pH-metro, pero este dispositivo es de uso hospitalario y no portátil. Las tiras reactivas no son fiables para una medición adecuada. Recientemente un dispositivo para medir el pH urinario, portátil y electrónico ha demostrado mayor precisión y exactitud en la medición del ph urinario, con buena aceptación por parte de los pacientes. MÉTODO: Realizamos una búsqueda bibliográfica en PUBMED y EMBASE utilizando los términos "URINARY pH", "Lithiasis", "Uro-Lihitiasis", "Urinary Stone", "Urinary pH measurement", con la finalidad de recopilar los artículos, libros, resúmenes y guías clínicas más relevantes en inglés y castellano sobre este tema. RESULTADOS: Recopilamos un total de 66 artículos, 3 libros, un resumen de un estudio presentado en el congreso americano de urología no publicado y las Guías Europeas de uro-litiasis sobre el efecto del pH en la formación y prevención de la litiasis urinaria. Cuatro artículos tratan específicamente sobre el pH urinario en la uro-litiasis, 5 artículos tratan sobre un dispositivo portable y electrónico para la medición del pH urinario, 5 artículos tratan sobre la medición del pH urinario con tiras reactivas. 1 artículo trata sobre la modificación del pH urinario para reducir incrustaciones de los catéteres doble J, 2 artículos tratan sobre la acidificación vía oral mediante metionina. El resumen seleccionado trata sobre el nuevo dispositivo portable para medir el pH urinario en pacientes cistinúricos. Los 3 libros tienen apartados específicos en dónde se comenta el papel del pH urinario en la uro-litiasis. Finalmente, en las Guías Europeas de Urología, se enfatiza el control del pH urinario en los apartados de prevención de formación de litiasis urinaria, tratamiento de litiasis úrica, fosfocálcica infecciosa/no infecciosa y cistina. CONCLUSIONES: El pH urinario es un factor reconocido en la comunidad científica - urológica dentro del estudio, seguimiento, tratamiento y prevención de los pacientes litiásicos. La medición del pH urinario es una herramienta muy útil. Las tiras reactivas no son precisas para la medición del pH y la toma de decisiones médicas. Actualmente diversos estudios han valorado un dispositivo para conseguir la medición del pH urinario de forma efectiva y sencilla por parte del paciente, de forma que se complemente con tratamientos médicos y no médicos para mantener el pH urinario en rangos no litogénicos, con buena aceptabilidad por parte de los pacientes

OBJECTIVE: Urinary pH is a factor that influences in urinary lithogenesis. It can condition the heterogeneous nucleation of calcium oxalate and the crystallization or dissolution of other substances such as uric acid, cystine and phosphates. Its exact and precise measurement is a tool to guide the treatment and prevention. The most accurate way to measure the pH is to use a glass electrode and a pH-meter, but this device is used in hospital's environment and is not portable. Test strips are not adequate for proper measurement. Recently, a portable and electronic device for measuring urinary pH has shown greater precision and accuracy in the measurement of urinary pH, with good acceptance by patients. METHOD: We carried out a bibliographic search in PUBMED and EMBASE using the terms "URINARY pH", "Lithiasis", "Uro-Lihitiasis", "Urinary Stone", "Urinary pH measurement", in order to compile articles, books, abstracts and the most relevant clinical guides in English and Spanish on this topic. RESULTS: We select a total of 66 articles, 3 books, an abstract of a study unpublished presented at the American urology congress and the European Guidelines on urolithiasis on the effect of pH on the formation and prevention of urolithiasis. Four articles deal specifically with the effect of urinary pH on urolithiasis, 5 articles deal with a new portable electronic device for measuring urinary pH, 5 articles dealt with the measurement of urinary pH with test strips and 1 article dealt with the modification of urinary pH to reduce fouling of double J catheters, 2 articles deal about the urinary acidification with oral methionine. The selected abstract deals with the new portable device for measuring urinary pH in cystinuric patients. The 3 selected books have specific sections where the role of urinary pH in urolithiasis is discussed. Finally, in the European Urology Guidelines, the control of urinary pH is emphasized in the sections of prevention of urolithiasis formation, treatment of uric lithiasis, infectious/ non-infectious phosphocalcic and cystine. CONCLUSIONS: Urinary pH is a recognized factor in the scientific-urological community for the study, monitoring, treatment and prevention of lithiasic patients. Urinary pH measurement is a very useful tool, but test strips are not suitable for pH measurement and medical decision making. Currently, several studies have evaluated a new device to achieve the measurement of urinary pH effectively and easily by the patient, keeping urinary pH in non-lithogenic ranges with the association of medical and non-medical treatments, and good acceptability from the patients

[Urinary pH relevance on urolithiasis management.] / Importancia del pH urinario en la urolitiasis.

OBJECTIVE: Urinary pH is a factor that influences in urinary lithogenesis. It can condition the heterogeneous nucleation of calcium oxalate and the crystallization or dissolution of other substances such as uricacid, cystine and phosphates. Its exact and precise measurement is a tool to guide the treatment and prevention. The most accurate way to measure the pH is to use a glass electrode and a pH-meter, but this device is used in hospital's environment and is not portable. Test strips are not adequate for proper measurement. Recently, a portable and electronic device for measuring urinary pH has shown greater precision and accuracy in the measurement of urinary pH, with good acceptance by patients. METHOD: We carried out a bibliographic search inPUBMED and EMBASE using the terms "URINARY pH", "Lithiasis", "Uro-Lihitiasis", "Urinary Stone", "Urinary pH measurement", in order to compile articles, books, abstracts and the most relevant clinical guides in English and Spanish on this topic. RESULTS: We select a total of 66 articles, 3 books, an abstract of a study unpublished presented at the American urology congress and the European Guidelines on urolithiasis on the effect of pH on the formation and prevention of urolithiasis. Four articles deal specifically with the effect of urinary pH on urolithiasis, 5 articles deal with a new portable electronic device for measuring urinary pH, 5 articles dealt with the measurement of urinary pH with test strips and 1 article dealt with the modification of urinary pH to reduce fouling of double J catheters, 2 articles deal about the urinary acidification with oral methionine. The selected abstract deals with the new portable device for measuring urinary pH in cystinuric patients. The 3 selected books have specific sections where the role of urinary pH in urolithiasis is discussed. Finally, in the European Urology Guidelines, the control of urinary pH is emphasized in the sections of prevention of urolithiasis formation, treatment of uric lithiasis, infectious/non-infectious phosphocalcic and cystine. CONCLUSIONS: Urinary pH is a recognized factor in the scientific-urological community for the study, monitoring, treatment and prevention of lithiasic patients. Urinary pH measurement is a very useful tool, but test strips are not suitable for pH measurement and medical decision making. Currently, several studies have evaluated a new device to achieve the measurement of urinary pH effectively and easily by the patient, keeping urinary pH innon-lithogenic ranges with the association of medical and non-medical treatments, and good acceptability from the patients.

OBJETIVO: El pH urinario es un factorque influye en la litogénesis urinaria de forma importante. Puede condicionar la nucleación heterogénea del oxalato de calcio y la cristalización o disolución de otras sustancias como el ácido úrico, cistina y fosfatos. Su medición exacta y precisa es una herramienta para orientar el tratamiento y la prevención. La forma más precisa de medirlo es la utilización de un electrodo de vidrio y un pH-metro, pero este dispositivo es de uso hospitalario y no portátil. Las tiras reactivas no son fiables para una medición adecuada. Recientemente un dispositivo para medir el pH urinario, portátil y electrónico ha demostrado mayor precisión y exactitud en la medición del ph urinario, con buena aceptación por parte de los pacientes.MÉTODO: Realizamos una búsqueda bibliográfica en PUBMED y EMBASE utilizando los términos "URINARYpH", "Lithiasis", "Uro-Lihitiasis", "Urinary Stone", "UrinarypH measurement", con la finalidad de recopilar los artículos, libros, resúmenes y guías clínicas más relevantes en inglés y castellano sobre este tema. RESULTADOS: Recopilamos un total de 66 artículos, 3 libros, un resumen de un estudio presentado en el congreso americano de urología no publicado y las Guías Europeas de uro-litiasis sobre el efecto del pH en la formación y prevención de la litiasis urinaria. Cuatro artículos tratan específicamente sobre el pH urinario en la uro-litiasis, 5 artículos tratan sobre un dispositivo portable y electrónico para la medición del pH urinario, 5 artículos tratan sobre la medición del pH urinario con tiras reactivas. 1 artículo trata sobre la modificación del pH urinario para reducir incrustaciones de los catéteres doble J, 2 artículos tratan sobre la acidificación vía oral mediante metionina. El resumen seleccionado trata sobre el nuevo dispositivo portable para medir el pH urinario en pacientes cistinúricos. Los 3 libros tienen apartados específicos en dónde se comenta el papel del pH urinario en la uro-litiasis. Finalmente, en las Guías Europeas de Urología, se enfatiza el control del pH urinario en los apartados de prevención de formación de litiasis urinaria, tratamiento de litiasis úrica, fosfocálcica infecciosa/no infecciosa y cistina. CONCLUSIONES: El pH urinario es un factor reconocido en la comunidad científica - urológica dentro del estudio, seguimiento, tratamiento y prevención de los pacientes litiásicos. La medición del pH urinario es una herramienta muy útil. Las tiras reactivas no son precisas para la medición del pH y la toma de decisiones médicas. Actualmente diversos estudios han valorado un dispositivo para conseguir la medición del pH urinario de forma efectiva y sencilla por parte del paciente, de forma que se complemente con tratamientos médicos y no médicos para mantener el pH urinario en rangos no litogénicos, con buena aceptabilidad por parte de los pacientes.

Phytotherapy and Herbal Medicines for Kidney Stones.

BACKGROUND: Kidney stones are one of the longest known and most common diseases in the urinary tract, with a prevalence that ranges from 1% to 20%. Many phytotherapeutic and herbal medicines have been described for the treatment and prevention of kidney stones. OBJECTIVE: The aim of this study was to perform a comprehensive review of publications on various phytotherapeutic and herbal medicines, including both clinical and animal studies. RESULTS: Phytotherapy may influence the risk of recurrence of calcium oxalate and uric acid stones. The most solid evidence relates to Phyllanthus niruri, one of the most studied phytotherapeutics; findings suggest that it interferes with calcium oxalate crystallization, reduces hyperoxaluria and hyperuricosuria, and increases the efficacy of shock wave lithotripsy due to reduced crystallization, without significant adverse effects. Theobromine has been shown to reduce the crystallization of uric acid in patients and appears to be a promising supplement to treat such stones. CONCLUSION: Many phytotherapeutic and herbal agents have been studied for the treatment of urolithiasis, most of them only in a small number of patients or in animal models. Further randomized clinical trials are needed to evaluate the effects of these agents on kidney stones.

Systematic Review and Meta-Analysis Comparing Fluoroless Ureteroscopy and Conventional Ureteroscopy in the Management of Ureteral and Renal Stones.

Context: Stone recurrence is frequent in stone formers, and repeated diagnostic and therapeutic procedures in recurrent stone formers place patients and urologists at a significant risk of radiation-related effects. Objective: To assess the efficacy and safety of fluoroless ureteroscopy (fURS) compared with conventional ureteroscopy (cURS) in the management of ureteral and renal stones. Evidence Acquisition: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies providing data on the stone-free rate (SFR), secondary procedures, operative time (OT), and complication rate for fURS and cURS were included. An overall analysis and a subgroup analysis based on the stone target (ureteral stones, renal stones, or a combination thereof) were performed. Evidence Synthesis: A total of 23 studies were included, recruiting 4029 patients. Pooled data showed that in comparison with cURS, fURS exhibited a similar SFR (odds ratio [OR]: 0.99; 95% confidence interval [CI]: 0.92 to 1.06; p = 0.709), without significant differences in overall intraoperative complication rate (OR: 0.73; 95% CI: 0.33 to 1.63; p = 0.446), overall postoperative complication rate (OR: 0.98; 95% CI: 0.59 to 1.63; p = 0.949), major postoperative complication rate (Clavien ≥3; OR: 0.46; 95% CI: 0.14 to 1.53; p = 0.205), OT (standardized mean difference [SMD]: 0.07; 95% CI: -0.15 to 0.29; p = 0.537), hospital stay (SMD: -0.12; 95% CI: -0.26 to 0.02; p = 0.084), or secondary procedures (OR: 1.20; 95% CI: 0.58 to 2.49; p = 0.616). The subgroup analysis revealed no differences in outcomes according to the stone target. We also identified a rate of conversion to the conventional technique of 5% (95% CI: 3% to 7%). Conclusions: The available data suggest that for the treatment of ureteral and renal stones, fURS offers a similar SFR to that provided by the cURS without any increase in complication rate, OT, hospital stay, or secondary procedures. Critical review of the dogmatic routine use of fluoroscopy during ureteroscopy may be warranted.

Oral Acidification with l-Methionine as a Noninvasive Treatment for Encrusted Uropathy.

Background: Encrusted uropathy (EU) is a rare disease caused by urea-splitting bacteria, most commonly Corynebacterium urealyticum, whose incidence is increasing. Standard treatment is based on pathogen-directed antibiotic therapy, urinary diversion, bladder instillations, and surgical resection of urinary calcifications. Case Presentation: We present the case of a 60-year-old man with symptomatic bilateral encrusted pyelitis and cystitis with acute renal failure. We initially treated the patient with antibiotic therapy, urinary diversion, and oral acidification with acetohydroxamic acid, achieving negative urinary cultures. Because of the persistence of encrusted pyelitis, the patient was discharged on oral l-methionine 500 mg bid and 12 months later the encrustations had almost disappeared. Finally, we performed right retrograde intrarenal surgery to remove a persistent small calcification. Conclusion: Oral urinary acidification with l-methionine is a valid treatment for urinary encrustations in EU, with no complications reported. Complete resolution of the calcifications may be achieved without the need for invasive processes and unnecessary manipulation of the urinary system.

Simultaneous and synchronous bilateral endoscopic treatment of urolithiasis: a multicentric study.

INTRODUCTION: The general prevalence of bilateral urolithiasis has risen to 15% and bilateral non-simultaneous treatment has been reported to have good outcomes. The objective of this study was to evaluate the effectiveness and safety of simultaneous bilateral endoscopic surgery (SBES). MATERIAL AND METHODS: An international multicenter analysis was performed between May 2015 and December 2017. All patients with bilateral stone disease that underwent SBES were included. Patients were treated under general anesthesia in either the supine or lithotomy position. Demographic, clinical, intraoperative and postoperative data were analyzed. RESULTS: A total of 47 patients were included. Mean age was 53.8 years and 70% of the patients were males. The mean American Society of Anesthesiology (ASA) score was 2. The mean diameter of right- and left-sided stones was 29.43 mm (2-83 mm) and 31.15 (4-102 mm), respectively. Staghorn stones were treated in 18 cases (8 right-sided and 10 left-sided), four of them were defined as complete staghorn. The procedures performed were 42 cases of bilateral URS and PCNL and ureteroscopy. Additionally, 5 bilateral flexible ureteroscopy (fURS) cases were described. Intraoperative complications occurred in five patients: four of them were classified as Clavien-Dindo (CD) I and one as CD II. Postoperatively, there were two cases with CD I, 6 with CD II and one CD IIIa.The stone-free status was 70%. Residual stones (30%) were detected only on the side treated for high-volume (complete) staghorn calculi. CONCLUSIONS: SBES is a feasible, effective and safe procedure. It may potentially avoid repeated anesthetic sessions as needed for staged procedures and reduce the length of patients' hospital stay.