Seguridad, consejos y límites para el uso del láser en la cirugía retrógrada intrarrenal / Laser safety, warnings, and limits in retrograde intrarenal surgery

Objetivo Analizar la información actual sobre la seguridad del láser en la cirugía retrógrada intrarrenal (CRIR), centrándonos en las dos principales tecnologías láser que utilizamos en urología, el láser de holmio:itrio-aluminio-granate (Ho:YAG) y el láser de fibra de tulio (TFL). Métodos Revisión narrativa de los artículos más relevantes publicados en las bases de datos Medline y Scopus sobre este tema. Resultados Los láseres TFL y Ho:YAG con ajustes similares (0,2 J/40 Hz) tienen un aumento de temperatura promedio por volumen similar y la tasa de calentamiento promedio aumenta proporcionalmente a la potencia del láser, especialmente cuando se utilizan frecuencias altas. Datos preclínicos recientes que comparan ambas tecnologías láser con diferentes ajustes del láser coinciden en que cuando la energía suministrada aumenta a expensas de frecuencias más altas, el daño térmico también aumenta. Las frecuencias más altas, a pesar del aumento de temperatura en el medio de irrigación, pueden causar lesiones térmicas accidentales por láser. Conclusiones El uso de ajustes de baja frecuencia y una irrigación adecuada es fundamental para evitar lesiones térmicas en la litotricia endoscópica con láser (LEL). Además, se recomienda el uso de gafas de seguridad láser en la LEL con Ho:YAG y TFL. (AU)

Objective To analyze the current information about laser safety in retrograde intrarenal surgery (RIRS), focusing on the two main laser technologies that we use in urology, the holmium:yttrium-aluminum-garnet (Ho:YAG) laser, and the thulium fiber laser (TFL). Methods Narrative overview of the most relevant articles published in Medline and Scopus databases about this subject. Results TFL and Ho:YAG laser at similar settings (0.2 J/40 Hz) have similar volume-averaged temperature increase and the average heating rate increase proportionally to laser power, especially when high frequencies are used. Recent preclinical data, comparing both laser technologies at different laser settings, agreed that when the delivered energy increases in expenses of higher frequencies, the thermal damage increases too. Higher frequencies, despite of the rise of temperature in the irrigation medium, can cause accidental thermal lasering lesions. Conclusions The use of low frequency settings and a proper irrigation is critical to avoid thermal injury in endoscopic laser lithotripsy (ELL). In addition, the use of laser safety eyeglasses is recommended in Ho:YAG and TFL ELL. (AU)

Aplicaciones clínicas, experimentales y resultados del uso de diferentes dispositivos de aspiración en la cirugía intrarrenal retrógrada. Revisión sistemática / Experimental and clinical applications and outcomes of using different forms of suction in retrograde intrarenal surgery. Results from a systematic review

Objetivo Identificar los últimos avances en los dispositivos de aspiración para la cirugía retrógrada intrarrenal (CRIR) y la ureteroscopia en el tratamiento de la litiasis, y evaluar los resultados de su aplicación. Procedimiento El 4 de enero de 2023 se realizó una búsqueda bibliográfica sistemática en Scopus, PubMed y EMBASE. Solo se incluyeron artículos en inglés; se aceptaron estudios en la población pediátrica y estudios en adultos. Se excluyeron los estudios duplicados, los informes de casos, las cartas al editor y los resúmenes de congresos. Hallazgos principales Se seleccionaron 21 trabajos. Se han propuesto varios sistemas de aspiración para la CRIR: a través de la vaina de acceso ureteral o directamente por el endoscopio. La inteligencia artificial también puede desempeñar un papel, monitorizando los valores de la presión y del flujo de irrigación. Todas las técnicas propuestas mostraron resultados perioperatorios satisfactorios en cuanto a tiempo quirúrgico, tasa libre de cálculos (TLC) y fragmentos residuales. Además, la reducción de la presión intrarrenal (mediante la aspiración) también se asoció a una tasa de infección menor. Incluso los estudios que incluyen cálculos renales con un diámetro de 20mm o superior informan de una mayor TLC y una reducción de las complicaciones postoperatorias. Sin embargo, la falta de parámetros bien establecidos para la presión de la aspiración y el flujo de líquido impide la estandarización del procedimiento. Conclusión Como ha sido demostrado en los estudios incluidos, el uso de dispositivos de aspiración en el tratamiento quirúrgico de los cálculos urinarios favorece la obtención de una TLC mayor y reduce las complicaciones infecciosas. La CRIR con sistema de aspiración podría sustituir a la técnica tradicional, gracias a sus ventajas asociadas al control de la presión intrarrenal y aspiración del polvo fino. (AU)

Objective To identify the latest advances in suction devices and evaluate their effect in Retrograde intrarenal surgery (RIRS) and ureteroscopy for stones. Basic procedures A systematic literature search was performed on 4th January 2023 using Scopus, PubMed, and EMBASE. Only English papers were included; both pediatric and adult studies were accepted. Duplicate studies, case reports, letters to the editor, and meeting abstracts were excluded. Main findings Twenty-one papers were selected. Several methods have been proposed for suction use in RIRS, such as through the ureteral access sheath or directly to the scope. Artificial intelligence can also regulate this system, monitoring pressure and perfusion flow values. All the proposed techniques showed satisfactory perioperative results for operative time, stone-free rate (SFR), and residual fragments. Moreover, the reduction of intrarenal pressure (induced by aspiration) was also associated with a lower infection rate. Even the studies that considered kidney stones with a diameter of 20mm or higher reported higher SFR and reduced postoperative complications. However, the lack of well-defined settings for suction pressure and fluid flow prevents the standardization of the procedure. Conclusion Aspiration device in the surgical treatment of urinary stones favours a higher SFR, reducing infectious complications, as supported by the included studies. RIRS with a suction system provided to be a natural successor to the traditional technique, regulating intrarenal pressure and aspirating fine dust. (AU)

¿Cómo calcular el volumen litiásico y cuál es su aplicación quirúrgica? / How to estimate stone volume and its use in stone surgery: A comprehensive review?

Objetivo Las guías actuales para el tratamiento intervencionista sugieren el diámetro acumulativo de la litiasis (DAL) como factor decisivo en la elección del tratamiento quirúrgico óptimo (ureteroscopia [URS], litotricia extracorpórea por ondas de choque [LEOCh] y nefrolitotomía percutánea [NLPC]). El volumen litiásico (VL) se ha introducido recientemente para obtener una estimación más precisa de la carga litiásica. El objetivo de esta revisión es resumir los métodos disponibles para calcular el VL y su aplicación quirúrgica. Material y métodos En diciembre de 2022 se realizó una revisión sistemática de la literatura mediante búsquedas en las bases de datos Embase, Cochrane y Pubmed. Los artículos se consideraron elegibles si describían la medición del VL o la tasa libre de litiasis (TLL) tras diferentes modalidades de tratamiento (LEOCh, URS, NLPC) o la expulsión espontánea, basándose en la medición del VL. Dos revisores evaluaron de forma independiente la elegibilidad y la calidad de los artículos y realizaron la extracción de datos. Resultados En total se incluyeron 28 estudios. Todos los estudios utilizaron diferentes técnicas para calcular el VL. La medición automática del volumen pareció ser más precisa que la estimación del volumen. Los estudios in vitro mostraron que la medición automática del volumen se ajustaba más al volumen real de la litiasis, con una menor variabilidad interobservador. A diferencia de la NLPC y la LEOCh, en la URS se observó que el VL era un mejor predictor de mejor la TLL que el diámetro litiásico mayor o el diámetro acumulativo en litiasis >20mm. Conclusiones Calcular el VL —de forma manual o automática— es factible, y probablemente se ajuste más a la carga litiásica real. Aunque en el caso de las litiasis grandes tratadas mediante cirugía intrarrenal retrógrada el VL parece predecir mejor la TLL, la superioridad del VL en todas las cargas litiásicas y para todos los tipos de tratamiento está aún por demostrar. ... (AU)

Objective Current interventional guidelines refer to the cumulative stone diameter to choose the appropriate surgical modality (ureteroscopy (URS), extracorporeal shockwave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL)). The stone volume (SV) has been introduced recently, to better estimate the stone burden. This review aimed to summarize the available methods to evaluate the SV and its use in urolithiasis treatment. Material and methods A comprehensive review of the literature was performed in December 2022 by searching Embase, Cochrane and Pubmed databases. Articles were considered eligible if they described SV measurement or the stone free rate after different treatment modalities (SWL, URS, PCNL) or spontaneous passage, based on SV measurement. Two reviewers independently assessed the eligibility and the quality of the articles and performed the data extraction. Results In total, 28 studies were included. All studies used different measurement techniques for stone volume. The automated volume measurement appeared to be more precise than the calculated volume. In vitro studies showed that the automated volume measurement was closer to actual stone volume, with a lower inter-observer variability. Regarding URS, stone volume was found to be more predictive of stone free rates as compared to maximum stone diameter or cumulative diameter for stones >20mm. This was not the case for PCNL and SWL. Conclusions Stone volume estimation is feasible, manually or automatically and is likely a better representation of the actual stone burden. While for larger stones treated by retrograde intrarenal surgery, stone volume appears to be a better predictor of SFR, the superiority of stone volume throughout all stone burdens and for all stone treatments, remains to be proven. Automated volume acquisition is more precise and reproducible than calculated volume. (AU)

Cystinuria Complicated by Anuria From Bilateral Obstructing Stones Requiring Bilateral Mini Percutaneous Nephrolithotomy in a 22-Month-Old.

Pediatric nephrolithiasis is increasing in incidence and presents differently compared to adults. We report a case of nephrolithiasis in a pediatric patient, presenting with complaints of emesis, anuria, hematuria, and abdominal distension, leading to a diagnosis of bilateral obstructing cystine stones requiring bilateral percutaneous nephrolithotomy. Pediatric patients with anuria should be evaluated for bilateral nephrolithiasis as an etiology. Calculous anuria requires prompt recognition of the pathologic process and relief of the obstruction with close follow-up and supportive care until definitive stone management. Bilateral percutaneous nephrolithotomy can provide definitive surgical intervention without significant morbidity.

Valoración del impacto de la tasa libre de litiasis en los resultados de la evaluación metabólica / Is stone free status really necessary for metabolic evaluation following stone removal procedures?

Objetivo Evaluar si la tasa libre de litiasis afecta a los resultados del estudio metabólico en pacientes con alto riesgo de litiasis recidivante tras tratamiento completo mediante ureteroscopia. Pacientes y métodos Un total de 78 pacientes sometidos a cirugía retrógrada intrarrenal (CRIR) para el tratamiento de litiasis fueron incluidos en este estudio. Cuatro semanas después del tratamiento, los casos se dividieron en dos grupos en base a los resultados de la tomografía computarizada sin contraste (TCSC). Los casos del grupo 1 (n=54) presentaban una tasa libre de litiasis del 100% y los del grupo 2 (n=24) presentaban litiasis residuales en el riñón. Cuatro semanas después de la ureteroscopia flexible (URF) se realizó un análisis completo de orina de 24h a todos los pacientes de ambos grupos, para detectar los factores de riesgo implicados en la litogénesis. Los resultados del estudio metabólico (orina de 24h y suero) se compararon entre los dos grupos. Resultados La evaluación preoperatoria en orina y suero de los factores de riesgo asociados a la formación de cálculos no reveló diferencias estadísticas entre los dos grupos. El análisis comparativo de los factores de riesgo implicados en la formación de la litiasis mediante pruebas de orina de 24h tampoco reveló diferencias estadísticamente significativas entre los resultados preoperatorios y postoperatorios en los casos del grupo 2 con cálculos residuales. Tampoco se observaron diferencias significativas entre las medias de las variables séricas preoperatorias y postoperatorias de ambos grupos. Conclusiones Según nuestros resultados, y dada la similitud de los hallazgos obtenidos en los estudios metabólicos de los casos con y sin litiasis residual, la tasa libre de litiasis puede no constituir un factor imprescindible para la realización del estudio metabólico detallado (suero y orina de 24h) tras las intervenciones endourológicas para la extracción de los cálculos renales. (AU)

Objective To evaluate the impact of stone free status on the outcomes of metabolic evaluation in recurrent stone formers after ureteroscopic stone removal. Patients and methods A total of 78 patients undergoing retrograde intrarenal surgery (RIRS) for renal stones were included and cases were divided into two groups after 4 weeks based on the NCCT findings. While cases in the Group 1 (n=54) was completely stone free, cases in Group 2 (n=24) had residual fragments in the kidney. A full 24-hour urine analysis for relevant stone forming risk factors has been performed after 4 weeks following the fURS procedures in all patients of both groups. Outcomes of metabolic evaluation (24-hour urine and serum) have been comparatively evaluated in both groups. Results Evaluation of the preoperative serum and urine stone forming risk factors revelaed no statistical difference in both groups. Comparative evaluation of the 24-hour urinary stone forming risk factors also revealed no statistically significant difference between preoperative and postoperative findings in cases of Group 2 with residual stones. Last but not least, no significant difference was observed between the mean preoperative and postoperative serum variables between two groups. Conclusions Our results show that in the light of the similar metabolic evaluation outcomes obtained in cases with and without residual fragments, ‘stone free status’ may not be an essential factor to perform a detailed metabolic evaluation (24-hour urine analysis and serum parameters) after endourological stone removal procedures. (AU)

Uso de vaina asistida por vacío en mininefrolitotomía percutánea (mini-NLPC) en decúbito supino / Vacuum-assisted access sheath in supine mini-percutaneous nephrolithotomy (mini-PCNL)

Introducción La vaina de acceso asistida por vacío es un nuevo dispositivo para el tratamiento de los cálculos renales mediante nefrolitotomía percutánea (NLPC). Objetivo Nuestro objetivo fue comparar la tasa libre de litiasis (TLL) y las complicaciones entre la mini-NLPC estándar y la asistida por vacío (VaNLPC). Método Estudio retrospectivo de pacientes intervenidos mediante mini-NLPC y VaNLPC desde enero de 2018 hasta junio de 2022. La VaNLPC se realizó con una vaina desechable (ClearPetra®) que permite la conexión de aspiración por un canal lateral facilitando la extracción de fragmentos. Se recogieron las características basales de los pacientes, los resultados quirúrgicos y los datos perioperatorios y postoperatorios. Se compararon en cuanto a las complicaciones y la TLL. Resultados Identificamos 136 pacientes, 57 (41,9%) intervenidos con VaNLPC y 79 (58,15%) con mini-NLPC. El tiempo quirúrgico medio fue significativamente menor en el grupo VaNLPC (95 min) que en el mini-NLPC (146 min; p = 0,001). La técnica tubeless se realizó con mayor frecuencia en el grupo VaNLPC (61,4 vs. 34,2%; p = 0,002). No se observaron diferencias en las complicaciones postoperatorias. El tiempo medio de hospitalización fue significativamente inferior en el grupo VaNLPC con 1,7 días por paciente frente a 2,7 días en el grupo mini-NLPC (p = 0,001). No hubo diferencias en la TLL a los tres meses entre VaNLPC (71,9%) y mini-NLPC (71,8%; p = 0,848). Conclusiones Los pacientes tratados con VaNLPC obtuvieron resultados comparables a la mini-NLPC, mostrando una TLL igual con similares complicaciones infecciosas. Como potenciales beneficios de la VaNLPC, se postulan menor tiempo quirúrgico y estancia postoperatoria. (AU)

Introduction The vacuum-assisted access sheath is a new device for the treatment of kidney stones with percutaneous nephrolithotomy (PCNL). Objective Our aim was to compare the stone-free rate (SFR) and complications between standard mini percutaneous nephrolithotomy (mini-PCNL) and vacuum-assisted PCNL (Va-PCNL). Methods Retrospective study of patients undergoing mini-PCNL and Va-PCNL from January 2018 to June 2022. Va-PCNL was performed with a disposable sheath (ClearPetra) with continuous high-flow irrigation and vacuum fluid dynamics for easier stone fragment removal. Baseline patient characteristics, surgical outcomes, perioperative and postoperative data were collected. We compared SFR and complications. Results A total of 136 patients were identified, 57 (41,9%) underwent Va-PCNL and 79 (58,15%) mini-PCNL. Mean operative time was significantly shorter in the Va-PCNL group (95 min.) than in mini-PCNL (146 min.; P = .001) group. The tubeless technique was performed more frequently in Va-PCNL group (61,4% vs. 34,2%; P = .002). We did not observe any differences in postoperative complications. The mean hospital stay was significantly lower in Va-PCNL with 1,7 ± 1,9 days per patient compared with 2,7 ± 1,5 days in the mini-PCNL group (P = .001). There were no differences in SFR at 3 months between Va-PCNL (71,9%) and mini-PCNL (71,8%; P = .848). Conclusion Patients treated with Va-PCNL had comparable results to mini-PCNL, showing equal SFR with similar infectious complications rates. Potential benefits of Va-PCNL include shorter operative time and postoperative stay. (AU)

The Surgical Management of Urolithiasis: A Review of the Literature.

The incidence of stone disease has increased significantly in the past 30 years, with a reported prevalence of 11% of the U.S. population in 2022, up from 9% in 2012 and 5.2% in 1994.1 While prevention is a vital aspect of management, many patients present with symptomatic urolithiasis requiring surgical management. Emerging advances in endoscopy and technology has led to a dynamic shift in the surgical management of stone disease. This paper will serve as a comprehensive review to inform urologic and non-urologic medical professionals alike, as well as the layperson, on the surgical treatment of nephrolithiasis, starting from the initial evaluation, laboratory and radiographic studies, and various surgical options. Additionally, the nuances of managing the pediatric and pregnant patient with nephrolithiasis will be explored. Using the most up-to-date urologic data, our aim is to provide a comprehensive resource for readers who interact with patients experiencing acute episodes of urolithiasis.

Rare Presentation of Primary Hyperparathyroidism in a Young Woman.

Even though primary hyperparathyroidism (PHPT) is a common endocrine disorder, due to better and more regular screening, the usual presentation is only seen in less than 15% of cases of PHPT. The authors present the case of a young female patient with a previous medical history of depression and nephrolithiasis, with one year of bone pain, that had become progressively worse and disabling. In the initial work-up, several lytic bone lesions and moderate hypercalcemia were found, leading to admission of the patient in the Internal Medicine ward for investigation and treatment. The ensuing investigation revealed PHPT due to hyperfunctioning parathyroid adenoma. The patient underwent a parathyroidectomy and at the follow-up assessment two months after discharge, she reported no symptoms and a computer tomography scan showed regression of the lytic lesions. This case is a reminder that severe symptomatic PHPT, a rare form in developed countries nowadays, still exists, and even though it is a medical condition, collaboration with surgical specialties is necessary to ensure the best possible treatment and prognosis.

Complicaciones frecuentes en pacientes con nefrolitotomía percutánea / Common complications in patients with percutaneous nephrolithotomy

RESUMEN La nefrolitotomía percutánea es un procedimiento estandarizado para el tratamiento de la litiasis renal. El objetivo de esta comunicación fue describir las complicaciones que más incidieron en los pacientes que fueron atendidos en el Hospital Universitario Clínico-Quirúrgico «Arnaldo Milián Castro¼, en el servicio de Urología, de enero de 2015 a diciembre de 2019, a los cuales se les realizó nefrolitotomía percutánea, así como el tratamiento que recibieron y su evolución. Este estudio mostró bajo índice de complicaciones, lo que guarda relación con el poco tiempo utilizado para realizar esta técnica. Esto resultó beneficioso ya que contribuyó a la corta estadía hospitalaria y disminuyó el consumo de materiales e insumos médicos. También representa un gran logro para los médicos y sobre todo para el paciente, el cual puede recuperarse en un menor período de tiempo y vincularse rápidamente a su vida diaria.

ABSTRACT Percutaneous nephrolithotomy is a standardized procedure for the treatment of kidney stones. The objective of this communication was to describe complications, treatment and evolution of patients who underwent a percutaneous nephrolithotomy in the Urology service at "Arnaldo Milián Castro" Clinical and Surgical University Hospital from January 2015 to December 2019. This study showed a low rate of complications, which is related to the short time used to perform this technique. This was beneficial since it contributed to the short hospital stay and decreased the consumption of medical materials and supplies. It also represents a great achievement for doctors and above all for the patients, who can recover in a shorter period of time and be quickly returned to their daily life.

Nephrolithiasis management and outcomes in pediatric patients with limited mobility.

INTRODUCTION AND OBJECTIVES: Pediatric patients with limited lower extremity mobility may be at increased risk of developing nephrolithiasis due to bone mineral metabolic derangements. This study sought to assess whether nephrolithiasis management and related outcomes differ between ambulatory versus non-ambulatory pediatric patients. METHODS: This was a retrospective review of ambulatory and non-ambulatory pediatric patients with nephrolithiasis from 2010 to 2021 from a single tertiary care center. Demographics, surgical history, stone compositions, and 24-h urine data were reviewed. Adjusted logistic and linear regression models were utilized to assess whether mobility status was associated with nephrolithiasis-related management and outcomes, including: age at first stone; requiring surgical intervention for stones; number of surgeries; stone compositions; urine culture results; and completion of 24-h urine studies. RESULTS: Among 339 pediatric patients with nephrolithiasis, 67 (19.8%) were non-ambulatory. In adjusted analyses, non-ambulatory patients had 3.24 times greater odds of requiring surgical intervention for stones (95% CI: 1.93-6.84; p < 0.0001); among those who required surgery, non-ambulatory patients required an average of 0.82 more surgical interventions (95% CI: 0.35-1.30; p = 0.0008) than ambulatory patients. Additionally, non-ambulatory patients had 5.28 times greater odds of having a positive urine culture at the time of surgery (95% CI: 2.35-14.08; p = 0.0001) and were significantly less likely to undergo 24-h urine studies (OR: 0.35; 95% CI: 0.15-0.83; p = 0.02). Stone composition significantly varied by mobility status, with non-ambulatory patients being significantly more likely to form calcium apatite (OR: 5.1; 95% CI: 2.18-11.93; p = 0.0002) or struvite (OR 3.72; 95% CI: 1.18-11.74; p = 0.03) stones, and significantly less likely to form calcium oxalate stones (OR: 0.19; 95 CI: 0.08-0.47; p = 0.0003). Among all patients, age at first stone occurred at a median age of 13.4 years (IQR: 8.2-16.4) and did not significantly differ by mobility status (p = 0.92). CONCLUSIONS: Patients with limited mobility required surgery for nephrolithiasis at significantly higher rates and had different stone compositions than ambulatory patients. Obtaining a 24-h urine study in patients with comorbidities affecting ambulation was uncommon, compared to ambulatory patients. Similarly to ambulatory patients, pediatric patients with limited mobility who develop nephrolithiasis tend to first present with stones in early adolescence.

Diferencias entre el Urocultivo Previo y el cultivo del Catéter doble J. Implicancias clínicas / DIFFERENCES BETWEEN PREVIOUS URINE CULTURE AND DOUBLE J CATHETER CULTURE. CLINICAL IMPLICATIONS

Las infecciones urinarias complicadas, dentro de las cuales se encuentran las asociadas a catéteres, son un hallazgo frecuente de la práctica clínica. Las complicaciones infecciosas después de los procedimientos urológicos son una fuente importante de morbimortalidad y consumen múltiples recursos sanitarios. La colonización bacteriana en el catéter ureteral juega un papel esencial en la patogénesis de la infección, y el uso de profilaxis antimicrobiana en urología es controvertido. El objetivo de nuestro trabajo fue evaluar la utilidad de la profilaxis antibiótica en la extracción del catéter doble J

Complicated urinary infections, among which are those associated with catheters, are a frequent finding in clinical practice. Infectious complications after urological procedures are an important source of morbidity and mortality and consume multiple healthcare resources. Bacterial colonization in the ureteral catheter plays an essential role in the pathogenesis of infection, and the use of antimicrobial prophylaxis in urology is controversial. Te objective of our work was to evaluate the usefulness of antibiotic prophylaxis in the extraction of the double J catheter

Impact of an Acute Care Urology Service on Timelines and Quality of Care in the Management of Nephrolithiasis.

Background: The acute care surgery model has led to improved outcomes for emergent surgical conditions, but similar models of care have not been implemented in urology. Our department implemented an acute care urology (ACU) service in 2015, and the service evolved in 2018. We aimed to evaluate the impact of the ACU model on the management of nephrolithiasis. Materials and Methods: We conducted a retrospective review of all patients with urology consults in the emergency department for nephrolithiasis, who required surgical intervention from 2013 to 2019. Patients were divided into three cohorts based on date of consultation: Pre-ACU (2013-2014), Phase 1 (2015-2017), and Phase 2 (2018-2019). Results: We identified 733 patients with nephrolithiasis requiring intervention (162 pre-ACU, 334 Phase 1, and 237 Phase 2). Before ACU implementation, median time from consult to definitive intervention was 36 days. After ACU implementation, median time to intervention decreased to 22 days in Phase 1 (p < 0.001) and 15 days in Phase 2 (p < 0.001). On multivariable Cox regression, the hazard of definitive intervention improved in Phase 1 (hazard ratio [HR] 1.90, p < 0.001) and in Phase 2 (HR 1.80, p < 0.001). Rates of primary definitive intervention without initial decompression and loss to follow-up were also significantly improved, compared to the pre-ACU cohort. Conclusions: Implementation of a structured ACU service was associated with improved time to treatment for patients with acute nephrolithiasis, as well as increased primary definitive intervention and improved follow-up care. This model of care has potential to improve patient outcomes for nephrolithiasis and other acute urological conditions.

Parathyroidectomy for nephrolithiasis in primary hyperparathyroidism: Beneficial but not a panacea.

BACKGROUND: Nephrolithiasis is a classic indication for parathyroidectomy in primary hyperparathyroidism patients; however, the effects of parathyroidectomy on nephrolithiasis recurrence are not well studied. The aim was to determine effect of parathyroidectomy on time to first nephrolithiasis recurrence and recurrence rate per patient-years. METHODS: A retrospective cohort study of patients diagnosed with primary hyperparathyroidism and at least one episode of nephrolithiasis was performed. The patients were divided into observation, presurgery, and postsurgery groups. Endpoints were time to first recurrence of nephrolithiasis and average recurrence rate per patient-years. RESULTS: The cohort was comprised of 1,252 patients. In addition, 334 (27%) patients underwent parathyroidectomy and 918 (73%) were observed. The surgical and nonsurgical groups differed significantly in age, sex, Charlson, calcium, and primary hyperparathyroidism level. Overall recurrence rate was 31.3%. The 5-, 10-, and 15-year recurrence-free survival rates were 74.4%, 56.3%, 49.5%, respectively (presurgery), 82.4%, 70.9%, 62.8%, respectively (postsurgery; P < .0001), and 86.3%, 77.7%, and 70.6%, respectively (observation). The presurgery group had an increased risk of first recurrence compared with the observation group (hazard ratio 1.89; 95% confidence interval, 1.44-2.47). The average recurrence rates among all surgical patients who recurred were 1 event per 4.3 patient-years presurgery versus 1 event per 6.7 patient-years postsurgery (P = .0001). CONCLUSION: Recurrent nephrolithiasis is a significant problem in patients with primary hyperparathyroidism. Parathyroidectomy prolongs the time to first recurrence and decreases the number of re-recurrences over time but does not eliminate recurrences. Observation may also be a reasonable approach in selected patients.

Is Retrograde Intrarenal Surgery as Safe for Children as It Is for Adults?

INTRODUCTION: The primary aim of this study is to compare the efficacy and safety of retrograde intrarenal surgery (RIRS) among the children and adults with similar stone burdens and locations. Also, the secondary aim of this study is to identify the factors affecting the stone-free rates (SFRs) of RIRS. METHODS: We retrospectively compared perioperative results, SFRs, and complication rates (CRs) between pediatric (group 1, n: 55) and adult (group 2, n: 220) age groups diagnosed with kidney stones and treated by flexible ureterorenoscopy using the same instruments. Furthermore, multivariate analysis was performed to determine the factors affecting the SFR. RESULTS: A total of 275 patients (pediatric group: 55; adult group: 220) were included in this study. The mean age of pediatric and adult groups was 7.2 ± 5.3 and 43.9 ± 15.1, respectively. The mean stone size was 13.9 ± 6.6 mm in the pediatric group compared to 14.8 ± 6.7 mm in the adult group (p = 0.35). Stone localizations and number were similar. JJ stenting for passive dilatation and use of UAS were higher in the pediatric group (p = 0.002; p = 0.017). However, postoperative double pigtail stenting rate was higher in the adult group (p < 0.001). Total CR was 13.8% and mostly Clavien I-II, and no difference was observed between the 2 groups (p = 0.541). The SFRs between the groups were similar (pediatric group: 81.8%; adult group: 78.2%; p = 0.554). On multivariate analysis, stone size (p < 0.001) and lower calyx stone (p < 0.001) were the negative predictive factors for SFR. CONCLUSION: There are small technical differences between pediatric patients and adult patients in our study, but RIRS in children is as safe and efficient as it is in adults.

The T-Tilt Position: A Novel Modified Patient Position to Improve Stone-Free Rates in Retrograde Intrarenal Surgery.

PURPOSE: Residual fragments following retrograde intrarenal surgery can lead to future stone episodes. The lower pole of the kidney presents a unique challenge as it is the most difficult location for retrograde intrarenal surgery. We investigated a modified patient position to increase stone-free rate by analyzing presence of residual fragments. We randomized patients into standard position and the T-Tilt position (15° Trendelenburg and 15° airplane away from the surgical side kidney). MATERIALS AND METHODS: In this prospective, randomized study, patients were randomized into the standard or T-Tilt position. Demographics, comorbidities and operative parameters were collected. Stone-free rate was determined with renal ultrasound and x-ray at 1-month followup. Postoperative complications were recorded up to 1 month. Variables were compared using Kruskal-Wallis test for continuous variables and chi-square test for categorical variables. RESULTS: A total of 138 patients were analyzed: 75 standard patients and 63 T-Tilt patients. The groups had similar patient and stone factors. The most common stone position was the lower pole (68.0% standard, 74.6% T-Tilt). Stone-free rates were significantly different: standard position was 76.7% and T-Tilt position was 92.1% (p=0.015). Stone-free rates for isolated lower pole stones were significantly different as well: standard position was 68.2% and T-Tilt position was 95.6% (p <0.001). Clavien-Dindo scores did not differ significantly (p=0.262). CONCLUSIONS: The T-Tilt patient position was associated with higher stone-free rates. It is an atraumatic, cost-effective technique. These results suggest that modifying patient positioning during retrograde intrarenal surgery improves stone-free rates.

Gender differences in the presentation, course and outcomes of primary hyperparathyroidism.

OBJECTIVE: To investigate gender-associated differences in the presentation, course, and outcomes of primary hyperparathyroidism (PHPT). STUDY DESIGN: A retrospective institutional cohort. METHODS: The database of a tertiary endocrine institute was retrospectively screened for patients treated for PHPT in 2010-2018. Clinical, biochemical, and imaging data were collected. Presentation, management, and outcome variables were compared by gender and by age at diagnosis (<50/≥50 years). RESULTS: The cohort included 182 women and 161 men diagnosed with PHPT at age 57.6 ± 12.8 and followed for 6.3 ± 5.5 years. There were no gender differences in age at detection of hypercalcemia and basal levels of serum and urinary calcium, serum PTH, and serum 25-hydroxyvitamin D. Men had a higher prevalence of nephrolithiasis (33 % vs 21 %, p = 0.01). Women had a higher frequency of osteoporosis (65 % vs 45 %, p < 0.001), and a lower mean lumbar spine T-score at PHPT diagnosis. At last follow-up, women had worse bone mineral density (BMD) results in all measured sites (lumbar spine, femoral neck, distal radius) and more fractures (34 % vs 20 %, p = 0.004), despite more frequent and longer pharmacological treatment of osteoporosis. On analysis by age, all these gender-associated differences were statistically significant only in patients diagnosed at age ≥50 years. Parathyroidectomy was performed in 52 % of women and 42 % of men (p = 0.06). CONCLUSION: The main differences between male and female patients with PHPT are the higher prevalence, more intensive pharmacological treatment, and worse outcomes of osteoporosis in women. Tailoring the optimal medical and/or surgical treatment for fracture prevention in patients with PHPT remains a major challenge, especially in older women.

Nefrolitotricia percutánea ambulatoria: nuestra experiencia en 156 casos / Ambulatory Percutaneous Nephrolithotomy: Our experience in 156 cases

OBJETIVOS: analizar y presentar nuestros resultados en el tratamiento de la litiasis renal mediante Nefrolitotricia Percutánea (NLP) ambulatoria en un mismo centro. MATERIALES Y MÉTODOS: entre agosto de 2013 y mayo de 2017 se realizó una recolección prospectiva de datos de los pacientes sometidos a NLP ambulatoria tubeless con catéter doble J o totally tubeless por litiasis renal. Se excluyeron aquellos pacientes con score de ASA >3. Se analizaron los datos preoperatorios, intra- y posoperatorios. Se clasificaron las complicaciones de acuerdo con el sistema de Clavien modificado. Se compararon los valores de hematocrito, hemoglobina, creatininemia y uremia pre- y posoperatoria a las 48 horas. RESULTADOS: en total, se operaron 156 pacientes, a los cuales se les dio el alta el mismo día de la cirugía. La suma de los diámetros máximos de las litiasis, en promedio, fue de 26,6 mm, 32 casos de litiasis coraliforme. La posición más utilizada fue la ventral, con un tiempo promedio de cirugía de 50 minutos. Se realizó NLP tubeless en 125 pacientes y totally tubeless en 29 casos. A 40 pacientes se les colocó un tapón de Surgicel en el tracto de acceso percutáneo. La tasa libre de cálculos fue del 84%, y en pacientes con litiasis coraliforme fue del 53%. No hubo complicaciones intraoperatorias y el 80% de los pacientes no presentó complicaciones. La tasa de reinternación fue del 3%. Si bien se hallaron diferencias significativas entre los valores pre- y posoperatorios de hematocrito y hemoglobina (40% y 13,3 g/dl vs. 39% y 12,8 g/dl; p=0,0001 y 0,0001, respectivamente), estas no fueron clínicamente significativas y solamente un paciente requirió de transfusión de sangre (0,6%). CONCLUSIONES: en nuestra experiencia, la NLP ambulatoria fue segura, con tasas libres de cálculos y complicaciones similares a las realizadas con internación.

OBJECTIVES: To assess the safety and feasibility of ambulatory percutaneous nephrolithotomy (PCNL) at a single institution. METHODS: Data collected prospectively of patients submit for ambulatory PCNL tubeless or totally tubeless between August 2013 and May 2017 were review. Exclusion criteria were patients with ASA score >3. Preoperative, intraoperative, and postoperative data were collected. Complications were classified using the Clavien sistem modified for PCNL. Properative and 48hs postoperative value of hematocrit, hemoglobin, creatininemia and uremia were compare. RESULTS: One hundred and fifty five patients underwent ambulatory PCNL. All patients were discharge the same day of surgery. The median of the sum of the maximum stone diameter was 26,6mm, 32 patients had staghorn calculus. We performed the majority of the surgerys in ventral position with a median time of 50 minutes. One hundred and twenty five patients underwent tubeless PCNL and totally tubeless 29 patients. In 40 cases we used Surgicel for sealing the percutaneous tract. Overall stone-free rate was 84% and 53% in staghorn cases. There were no intraoperative complications and 80% of the patients did not have any complications. Readmission rate was 3%. There was a significant decrease in the postoperative hematocrit and hemoglobin level (40% y 13,3 g/dl vs. 39% y 12,8 g/dl; p=0,0001 y 0,0001), this was not clinically significant. Only one patient required blood transfusion (0,6%). CONCLUSION: Ambulatory PCNL is safe with a stone-free rate, readmisions and complications similar to standard PCNL.

Effect of Active Aspiration and Sheath Location on Intrapelvic Pressure During Miniaturized Percutaneous Nephrolithotomy.

OBJECTIVE: To evaluate the effects of location of the tip of percutaneous sheath and nephroscope in the collecting system together with active aspiration on the Intrapelvic pressure measurements (IPP) during miniaturized percutaneous nephrolithotomy (miniPNL). MATERIALS AND METHODS: The data of 20 patients underwent miniPNL in supine position was collected prospectively. IPP measurements were done with an 8 Fr urodynamic pressure measurement catheter in 4 different settings with respect to location of tip of sheath and nephroscope. All 4 settings were repeated with active aspiration. Totally measurements were done and compared in 8 different settings for 90 seconds in each patient. RESULTS: Highest mean IPP measurements were recorded in setting II (35.3 ± 11.8 cm H2O) where the sheath was located in the calyx and the tip of the nephroscope was in the renal pelvis. When active aspiration was applied, the mean pressure measurements were significantly lower than the counterpart settings without aspiration (all P values <.0001). When the active aspiration was applied, intrarenal pressure measurements did not exceed 40 cm H2O in any settings in any of the patients. CONCLUSION: Location of the tip of the sheath and the nephroscope has significant effect on IPP measurements. Active aspiration significantly lowers the IPP and keeps it <40 cm H2O. Endourologists should be aware of possible alterations in IPP during miniPNL and active aspiration should be kept in mind as an effective solution to decrease the risk of complications related to high IPP.

Natural history of patients with infantile nephrolithiasis: what are the predictors of surgical intervention?

BACKGROUND: We evaluated the risk factors for the requirement of surgical intervention in infants with nephrolithiasis. METHODS: The medical records of 122 (156 kidney units (KU)) infants were reviewed. The clinical features, stone characteristics, changes in stone status, and treatment protocols were noted. The stone status of the KU was categorized into 3 groups according to the change in size between the first and last ultrasound: resolution, unchanged, and growth. RESULTS: The median age was 8 months (r: 2-12). The median length of follow-up was 16 months (r: 10-36). Resolution was detected in 94 KUs (60%). Stone growth was detected in 39 KUs (25%), and stone size was unchanged in 23 KUs (15%). Surgical intervention was required in 26 patients (17%). A history of intensive care unit (ICU) follow-up and a stone size > 5 mm at time of diagnosis were defined as independent risk factors for stone growth (p = 0.005, < 0.001, respectively). The surgical intervention rate was higher in stones > 5 mm and stones with pelvic localization (p = 0.018, 0.021, respectively). Stone resolution was higher in patients with stone size ≤ 5 mm (p = 0.018). CONCLUSION: A stone size > 5 mm at the time of diagnosis and a history of ICU follow-up are independent risk factors for stone growth. Pelvic localization of stones and stones > 5 mm are associated with an increased risk of surgical intervention.

Surface analysis of ureteral stent before and after implantation in the bodies of child patients.

The aim of this work was to determine which part of a double-J ureteral stent (DJ stents) showed the highest tendency to crystal, calculi, and biofilm deposition after ureterorenoscopic-lithotripsy procedure (URS-L) to treat calcium oxalate stones. Additionally, the mechanical strength and the stiffness of DJ stents were evaluated before and after exposure to urine. Obtained results indicated that the proximal (renal pelvis) and distal (urinary bladder) part is the most susceptible for post-URS-L fragments and urea salt deposition. Both, the outer and inner surfaces of the DJ ureteral stents were completely covered even after 7 days of implantation. Encrustation of DJ stents during a 31-day period results in reducing the Young's modulus by 27-30%, which confirms the loss of DJ stent elasticity and increased probability of cracks or interruption. Performed analysis pointed to the need to use an antibacterial coating in the above-mentioned part of the ureteral stent to prolong its usage time and to prevent urinary tract infection.