Intraoperative computed tomography for detection of residual stones in endourology procedures: systematic review and meta-analysis

ABSTRACT Background: Success rates in endourological procedures, notably percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS), have demonstrated suboptimal outcomes, leading to more reinterventions and radiation exposure. Recently, the use of intraoperative computed tomography (ICT) scans has been hypothesized as a promising solution for improving outcomes in endourology procedures. With this considered, we conducted a comprehensive systematic review and meta-analysis encompassing all available studies that evaluate the impact of the use of intraoperative CT scans on surgical outcomes compared to conventional fluoroscopic-guided procedures. Methods: This systematic review was conducted in accordance with PRISMA guidelines. Multiple databases were systematically searched up to December of 2023. This study aimed to directly compare the use of an ICT scan with the standard non-ICT-guided procedure. The primary endpoint of interest was success rate, and the secondary endpoints were complications and reintervention rates, while radiation exposure was also evaluated. Data extraction and quality assessment were performed following Cochrane recommendations. Data was presented as an Odds ratio with 95%CI across trials and a random-effects model was selected for pooling of data. Results: A comprehensive search yielded 533 studies, resulting in the selection of 3 cohorts including 327 patients (103 ICT vs 224 in non-ICT). Primary outcome was significantly higher in the experimental group versus the control group (84.5% vs 41.4% respectively, 307 patients; 95% CI [3.61, 12.72]; p<0.00001; I2=0). Reintervention rates also decreased from 32.6% in the control to 12.6% in the ICT group (OR 0.34; 95%CI [0.12,0.94]; p =0.04; I2= 48%), whereas complication rates did not exhibit significant differences. Radiation exposure was also significantly reduced in two of the included studies. Conclusion: This meta-analysis highlights a favorable outcome with intraoperative CT scan use in PCNL procedures, showing a considerable increase in SFR when compared to standard fluoroscopy and nephroscopy. Despite limited studies, our synthesis underscores the potential of ICT scans to significantly reduce residual stones and their consequences for endourology patients, as reinterventions and follow-up ionizing radiation studies.

Postoperative antibiotic prophylaxis for percutaneous nephrolithotomy and risk of infection: a systematic review and meta-analysis

ABSTRACT Purpose: The aim of this study is to perform a high-quality meta-analysis using only randomized controlled trials (RCT) to better define the role of postoperative antibiotics in patients undergoing percutaneous nephrolithotomy (PCNL). Materials and Methods: A literature search for RCTs in EMBASE, PubMed, and Web of Science up to May 2023 was conducted following the PICO framework: Population—adult patients who underwent PCNL; Intervention—postoperative antibiotic prophylaxis until nephrostomy tube withdrawal; Control—single dose of antibiotic during the induction of anesthesia; and Outcome—systemic inflammatory response syndrome (SIRS) or sepsis and fever after PCNL. The protocol was registered on the PROSPERO database (CRD42022361579). We calculated odds ratios (OR) and 95% confidence intervals (CI). A random-effects model was employed, and the alpha risk was defined as < 0.05. Results: Seven articles, encompassing a total of 629 patients, were included in the analysis. The outcome of SIRS or sepsis was extracted from six of the included studies, while the outcome of postoperative fever was extracted from four studies. The analysis revealed no statistical association between the use of postoperative antibiotic prophylaxis until nephrostomy tube withdrawal and the occurrence of SIRS/sepsis (OR 1.236, 95% CI 0.731 - 2.089, p=0.429) or fever (OR 2.049, 95% CI 0.790 - 5.316, p=0.140). Conclusion: Our findings suggest that there is no benefit associated with the use of postoperative antibiotic prophylaxis until nephrostomy tube withdrawal in patients undergoing percutaneous nephrolithotomy (PCNL). We recommend that antibiotic prophylaxis should be administered only until the induction of anesthesia in PCNL.

One week pre-operative oral antibiotics for percutaneous nephrolithotomy reduce risk of infection: a systematic review and meta-analysis

ABSTRACT Purpose The aim of this meta-analysis is to assess the efficacy of extended dose of preoperative antibiotics to reduce infectious risk in patients undergoing percutaneous nephrolithotomy (PCNL). Materials and Methods A literature search for prospective case-control studies or randomized controlled trials was done. PICO framework was used. Population: adult patients that underwent to PCNL; Intervention: extended dose preoperative antibiotic prophylaxis before PCNL; Control: short dose preoperative antibiotic prophylaxis before PCNL; and Outcome: systemic inflammatory response syndrome (SIRS) or sepsis, fever after PCNL and positive intraoperative urine and stone culture. This meta-analysis was registered in PROSPERO database under the number: CRD42022359589. Results Three RCT and two prospective studies (475 patients) were included. SIRS/sepsis outcome was retrieved from all studies included. Seven days preoperative oral antibiotics for PCNL was a protective factor for developing SIRS/sepsis (OR 0.366, 95% CI 0.234 - 0.527, p < 0.001). There was no statistical association between seven-day use of antibiotics and fever (OR 0.592, 95% CI 0.147 - 2.388, p = 0.462). Patients who received seven days preoperative antibiotics had lower positive intraoperative urine culture (OR 0.284, 95% CI 0.120 - 0.674, p = 0.004) and stone culture (OR 0.351, 95% CI 0.185 - 0.663, p = 0.001) than the control group. Conclusion one week of prophylactic oral antibiotics based on local bacterial sensitivity pattern plus a dose of intravenous antibiotics at the time of surgery in patients undergoing PCNL reduces the risk of infection.

Ultrasound guided endoscopic combined Intrarenal surgery - 10 steps for the success

ABSTRACT Background: Endoscopic combined intrarenal surgery (ECIRS) has been used to treat complex kidney stones (1). The combined use of ultrasound (US) has the potential to improve safety and reduce radiation exposure, however, it is still underutilized (2). Objectives: Our objective is to describe, in a step-by-step manner, the ultrasound-guided ECIRS (USG ECIRS) technique, in order to facilitate learning by urologists. Materials and Methods: We describe the 10 standardized steps that we recommend to achieve a good outcome, based on our previous experience on a high-volume kidney stone center. We recorded a case of a 37-year-old female patient with complex bilateral kidney stones that underwent a left simultaneous combined retrograde and antegrade approach. The 10 described steps are: 1 - case evaluation with CT scan (3); 2 - preoperative care with antibiotics and tranexamic acid; 3 - warm-up and training with phantoms; 4 - patient positioning in Barts flank free position; 5 - retrograde nephroscopy with flexible ureteroscope; 6 - US and endoscopic guided puncture; 7 - tract dilation under endoscopic view; 8 - stone fragmentation; 9 - status free checking and 10, kidney drainage. Images were captured by external and internal cameras, promoting a complete understanding of the procedure. The patient has signed a written informed consent form. Results: Puncture was achieved under US guidance with one attempt. Another puncture was necessary in the lower pole, parallel to the initial puncture, due to a large fragment. Surgical time was 140 min. Stone-free status was verified by retrograde and antegrade view. Kidney drainage was done with ureteral stent on string, removed after 7 days. Hb drop was 1.1 Hb/dL. The first postoperative day CT scan showed no residual stones and no complications. The patient was discharged after the CT and urethral catheter removal. Conclusion: The USG ECIRS seems to be a very efficient and reproducible technique for the treatment of complex kidney stones. Its use should be widespread.

The impact of COVID-19 in medical practice. A review focused on Urology

ABSTRACT COVID-19 pandemic is a rapidly spreading virus that is changing the World and the way doctors are practicing medicine. The huge number of patients searching for medical care and needing intensive care beds led the health care system to a burnout status especially in places where the care system was already overloaded. In this setting, and also due to the absence of a specific treatment for the disease, health authorities had to opt for recommending or imposing social distancing to relieve the health system and reduce deaths. All other medical specialties nondirectly related to the treatment of COVID-19 had to interrupt or strongly reduce their activities in order to give room to seriously ill patients, since no one knows so far the real extent of the virus damage on human body and the consequences of doing non deferrable procedures in this pandemic era. Despite not been a urological disease, the urologist needs to be updated on how to deal with these patients and how to take care of himself and of the medical team he works with. The aim of this article is to review briefly some practical aspects of COVID-19 and its implications in the urological practice in our country.

Bilateral simultaneous percutaneous nephrolithotomy versus staged approach: a critical analysis of complications and renal function

SUMMARY INTRODUCTION: Patients with bilateral kidney stones and burdened by large stones are challenging cases for endourologists. Simultaneous bilateral percutaneous nephrolithotomy (sbPCNL) is an option; however, it may be accompanied by important morbidity. An alternative is a staged PCNL, operating one side each time. Herein, we compare the impact of sbPCNL and staged PCNL on complication rates and renal function. METHODS: Patients who underwent sbPCNL or staged bilateral PCNL with a frame time of 6 months were searched in our prospectively collected kidney stone database. Groups were compared for age, gender, body mass index (BMI), comorbidities (classification by the American Society of Anesthesiology - ASA), stone size, Guy's score, stone-free status, renal function, blood loss, blood transfusion rate, complication rate, and length of hospital stay. RESULTS: Twenty-six patients and 52 kidney units were enrolled. The mean operative time was 134.7 min. Only 11.3% of cases had complications, all of them minor (Clavien ≤ 2). Overall, the stone-free rate was 61.50%. Comparing the groups, there was a significantly longer operative time in the sbPCNL group (172.5 vs. 126.3 min; p=0.016), as well as a higher transfusion rate (12.5% vs. 5.6%; p=0.036). There was no statistically significant difference in creatinine levels between the groups. Regarding the stone-free rate, there was a significantly higher proportion of patients in the staged PCNL group (64.9% vs. 43.8%; p=0.012). CONCLUSION: sbPCNL is a safe procedure; however, when compared to staged procedures it has a higher transfusion and lower stone-free rate.

RESUMO INTRODUÇÃO: Paciente com cálculos renais bilaterais e de grande volume são casos desafiadores para os endourologistas. A nefrolitotripsia percutânea bilateral simultânea (NLPbs) é um opção, entretanto esse procedimento pode ser acompanhado de morbidade importante. Uma alternativa é a NLP estagiada, operando um lado de cada vez. Aqui, nós comparamos o impacto da NLPbs e da NLP estagiada nas taxas de complicações e função renal. MÉTODOS: Pacientes que foram submetidos a NLPsb ou NLP stagiada com intervalo de até 6 meses foram pesquisados em nossa base de dados de cálculos renais prospectivamente coletada. Os grupos foram comparados em idade, gênero, índice de massa corpórea (IMC), comorbidades (classificação da Sociedade Americana de Anestesiologia - ASA), tamanho do cálculo, Classificação de Guys, taxa de pacientes livres de cálculos, função renal, perda sanguínea, taxa de transfusão, taxa de complicações e tempo de internação hospitalar. RESULTADOS: Vinte e seis paciente e 52 unidades renais foram incluídas. O tempo operatório médio foi de 134,7 min. Apenas 11.3% dos casos tiveram complicações, sendo todas menores (Clavien ≤ 2). No geral, a taxa de pacientes livres de cálculos foi de 61,5%. Comparando os grupos houve um tempo operatório significativamente maior no grupo NLPbs(172,5 vs. 126,3 min; p=0,016), assim como uma maior taxa de transfusão (12,5% vs. 5,6%; p=0.036). Não houve diferença significante nos níveis de creatinina entre os grupos. Em relação a taxa de doentes livre de cálculos houve uma proporção significativamente maior de pacientes livres de cálculos na NLP estagiada (64,9% vs. 43,8%; p=0,012). CONCLUSÃO: A NLPsb é um procedimento seguro, entretando quando comparada ao procedimento estagiado apresenta uma maior taxa de transfusão e uma menor taxa de pacientes livres de cálculos.

Renal manifestations of sarcoidosis: from accurate diagnosis to specific treatment

ABSTRACT Sarcoidosis is a multisystem granulomatous disease characterized by epithelioid noncaseating granulomas associated with clinical and radiologic findings. The cause of this disease is still uncertain. Sarcoidosis affects mostly lungs and lymph nodes and is not usually considered a urological disease, therefore, this etiology may be overlooked in several urological disorders, such as hypercalcemia, hypercalciuria and nephrolithiasis. It affects all races and genders. This review aims to describe the urological manifestations of sarcoidosis and to elucidate how the disease may affect the management of numerous urological conditions.

A comprehensive literature-based equation to compare cost-effectiveness of a flexible ureteroscopy program with single-use versus reusable devices

ABSTRACT Purpose to critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes. Materials and Methods A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included. Results 741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive financial cost-effective decision model to flexible ureteroscope acquisition. Conclusions The cost-effectiveness of a flexible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.

Differences in the percutaneous nephrolithotomy practice patterns among Latin American urologists with and without endourology training

ABSTRACT Purpose: Although the worldwide percutaneous nephrolithotomy (PCNL) practice pat- terns determined via a survey sent to members of the Endourological Society have been published, differences in PCNL practice patterns among Latin American urologists based on endourological or lithiasis training have not been published. To determine the PCNL practice patterns among Latin American urologists with and without training in endourology. Materials and Methods: The SurveyMonkey® web platform was used to develop a 27-item survey on PCNL for the treatment of renal stones, and the survey was sent via e- -mail and other electronic media to 2000 urologists from 15 Latin American countries. Endourology-trained (group 1) and nontrained urologists (group 2) were analyzed. The group results were compared using the chi-squared and Fisher's exact tests. SPSS version 20 for Windows was used for all analyses. Results: A total of 331 urologists responded to the survey (rate of 16.55%): 221 (66.7%) in group 1 and 110 (33.2%) in group 2). In groups 1 and 2, 91.9% and 63.2% performed PCNL, respectively: 85.1% and 58.5% used preoperative tomography, respectively; 12.7% and 4.7% used preoperative nephrolitometry nomograms, respectively: 45.2% and 32.1% used endoscopic combined intrarenal surgery, respectively: 68.3% and 38.7% used mul- tiple percutaneous tract realization, respectively: and 19.9% and 5.7% used minimally invasive PCNL, respectively (all p=0.0005). Conclusions: Statistically significant differences were observed in PCNL practice patterns of Latin American urologists with and without training in endourology. Specific training in endourology significantly influence the practice patterns of Latin American urologists.

What is the quickest scoring system to predict percutaneous nephrolithotomy outcomes? A comparative study among S. T. O. N. E score, guy's stone ccore and croes nomogram

ABSTRACT Objective: To compare the application time and the capacity of the nomograms to predict the success of Guy's Stone Score (GSS), S.T.O.N.E. Nephrolithometry (STONE) and Clinical Research Office of the Endourological Society nephrolithometric nomogram (CROES) of percutaneous nephrolithotomy (PCNL), evaluating the most efficient one for clinical use. Materials and Methods: We studied 48 patients who underwent PCNL by the same surgeon between 2010 and 2011. We calculated GSS, STONE and CROES based on pre-operative non-contrast computed tomography (CT) images and clinical data. A single observer, blinded to the outcomes, reviewed all images and assigned scores. We compared the application time of each nomogram. We used an analysis of variance for repeated measures and multiple comparisons by the Tukey test. We compared the area under the ROC curve (AUC) of the three nomograms two by two to determine the most predictive scoring system. Results: The immediate success rate was 66.7% and complications occurred in 16.7% of cases. The average operative time was 122 minutes. Mean application time was significantly lower for the GSS (27.5 seconds) when compared to 300.6 seconds for STONE and 213.4 seconds for CROES (p<0.001). There was no significant difference among the GSS (AUC=0.653), STONE (AUC=0.563) and CROES (AUC=0.641) in the ability to predict immediate success of PCNL. Conclusions: All three nomograms showed similar ability to predict success of PCNL, however the GSS was the quickest to be applied, what is an important issue for routine clinical use when counseling patients who are candidates to PCNL.

Use of the Uro Dyna-CT in endourology - the new frontier

ABSTRACT We describe the use of the Uro Dyna-CT, an imaging system used in the operating room that produces real-time three-dimensional (3D) imaging and cross-sectional image reconstructions similar to an intraoperative computerized tomography, during a percutaneous nephrolithotomy and a contralateral flexible ureteroscopy in a complete supine position. A 65 year-old female patient had an incomplete calyceal staghorn stone in the right kidney and a 10mm in the left one. The procedure was uneventful and the intraoperative use of the Uro Dyna-CT identified 2 residual stones that were not found by digital fluoroscopy and flexible nephroscopy at the end of surgery, helping us to render the patient stone-free in one procedure, which was confirmed by a postoperative CT scan. Prospective studies will define the real role of the Uro Dyna-CT for endourological procedures, but its use seems to be a very promising tool for improving stone free rates and decreasing auxiliary procedures, especially for complex cases.

The challenge of cystine and struvite stone formers: clinical, metabolic and surgical assessment

ABSTRACT Purpose: To compare the clinical, metabolic, and calculi characteristics of cystine and struvite stone patients after percutaneous nephrolithotripsy (PCNL). Material and Methods: Between January/2006-July/2013, 11 cystine stone patients were treated in our clinic. Of those, 3 were excluded due to incomplete follow-up. Eight cystine stone patients (2 with bilateral disease; 10 renal units-RU) were considered for further analysis. A cohort of 8 struvite stone formers (10RU) was matched having the same age, gender, body mass index (BMI) and Guys stone score. Analyzed parameters comprised demographic data, serum/urinary metabolic evaluation and surgical outcomes. Results: Both groups had 6 female patients. Groups were similar in regards to age, gender, BMI, stone burden, and serum creatinine (p=NS). All patients had PCNL as the first surgical treatment modality. Stone free rate (SFR) after the first PCNL tended to be lower (0%) in the cystine compared to the struvite group (40%)(p=0.08). Final SFR after secondary procedures increased to 70% in cystine and 80% in struvite patients (p=1.0); mean number of procedures to achieve stone free status was higher in the first group (3.57 vs. 2.0;p=0.028). Hypocitraturia was found in all patients, but struvite cases presented with lower mean urinary citrate levels (p=0.016). Other common abnormalities were elevated urinary pH (cystine 75% and struvite 62.5%;p=1.0) and low urinary volume (62.5%,37.5%;p=0.63). Conclusion: Multiple interventions and suboptimal stone free rates are trait of the significant stone burden of struvite and cystine patients. Underlying metabolic abnormalities characterized by increased urinary pH, hypocitraturia and low urinary volume are often encountered in both populations.

Percutaneous nephrolithotomy in patients with solitary kidney: a critical outcome analysis

To describe our experience with percutaneous nephrolithotomy (PCNL) in patients with solitary kidneys and analyze factors that can impact on intra-operative bleeding and postoperative complications.

Anuric renal failure after same-session bilateral atraumatic flexible ureteroscopy

We report the first known case of anuric renal failure after same-session bilateral atraumatic flexible ureteroscopy for renal calculi. Although, there is no consensus about stenting patients who undergo same-session bilateral ureteroscopy due to the lack of prospective randomized studies; strong consideration should be given to stenting the ureter at least one side to avoid this complication.