Predicting urine culture results in candidates for lithotripsy.

Background: Urological guidelines assert that "urine culture should be obtained" before surgical management of ureteral or kidney stones. Thus, many surgeries are delayed by 1-3 days until the results of urine culture are available. During this time, the patient frequently experience pain and possible kidney damage. We investigated the hypothesis that it is possible to predict the results of urine culture in candidates for surgical intervention using parameters that are accessible immediately upon admission. Materials and methods: A database of 1000 patients who underwent either percutaneous nephrolithotomy (PCNL) or ureteroscopy/retrograde intrarenal surgery was analyzed. Eleven parameters potentially related to urinary infections and accessible to the clinician at the emergency department were correlated with the preoperative urine culture results. Results: Of the patients, 234 (23.4 %) had positive cultures. On multivariate analysis, only sex, hydronephrosis grade, and history of previous nephrolithotomy were significantly associated with a positive preoperative urine culture. The risk of a positive culture can be easily determined from a simple table or an Excel-based calculator. This risk could be as low as 0.45% for a man without a history of PCNL and no hydronephrosis (4% in a woman with similar parameters) or as high as 79.5% in a man with a history of PCNL and hydronephrosis (85% in a woman with similar parameters). Conclusions: The risk of preoperative positive urine culture can be predicted using 3 parameters that are accessible upon admission. In low-risk cases, prompt surgical treatment can be provided, eliminating the anticipation time for urine culture results.

Timing of midstream urine culture before endourological procedure-can we do better?-A comparative study.

Endourological procedures are the mainstay of treatment for stone disease in the upper urinary system. Infection is a common complication, and urine cultures (UC) are often obtained preoperatively. In this study, we sought to investigate the role of positive UC in the 90 days prior to surgery (90PreOp) in predicting postoperative infectious complications in comparison to a single positive preoperative UC (PreOP). We compared the correlation between positive PreOp UCs and positive 90PreOp UCs with postoperative urosepsis, and a positive UC obtain proximal to obstruction (Prox UC) during percutaneous nephrolithotomy, ureteroscopy and a placement of nephrostomy tube or ureteral stent. Data from 140 consecutive patients were collected. PreOp UCs were positive in 15 (11%) of patients versus 31 of 140 (22%) positive 90PreOp UCs. All six sepsis events had a positive 90PreOp UC, and five had a positive PreOp UC. Fourteen (93.3%) out of 15 positive Prox UC had a positive 90PreOp UC, whereas only 7 (38.9%) had a positive 90PreOp UC. Positive 90PreOp UC outperformed PreOp UC in predicting positive Prox UC, OR = 12.8 (95% CI 3.70-44.30, p < 0.001), versus OR of 88.9 (95% CI 11.0-720.7, p < 0.001); sensitivity 93%(95% CI 68-100%) versus 47%(95% CI 21-73%); as well as area under the ROC curve(AUC), 0.90 (CI 0.80-0.95) for 90PreOp versus 0.70 (CI 0.56-0.82) for positive Prox UC. Uropathogen persistence was better identified when using 90PreOp UC (27%) than using PreOp UC (12%). We suggest reviewing UCs taken within 90 days preoperatively as this was found superior to a single preoperative midstream UCs in predicting postoperative infectious sequela after stone procedure.

Factors Predicting Operating Room Time in Ureteroscopy and Ureterorenoscopy.

BACKGROUNDS/AIMS: Operation room (OR) time is of great value affecting surgical outcome, complications and the daily surgical program with financial implications. METHODS: We retrospectively evaluated 570 consecutive patients submitted to ureteroscopy or ureterorenoscopy for the treatment of ureteral or renal stones. Demographic parameters, patient's stones characteristics, type of ureteroscope, surgeon experience and surgical theater characteristics were analyzed. OR time was calculated from the initiation of anesthesia to patient extubation. Multivariate analysis was conducted using a linear regression test with multiple parameters to identify predictors of OR time. RESULTS: Eight factors were identified as significant. These include total stones volume, ureteroscope used, stone number, nurses experience, radio-opacity of the stone on kidney-ureter-bladder X-ray, main surgeon experience, operating room type, and having a nephrostomy tube prior to surgery. CONCLUSIONS: The surgical team experience and familiarity with endourological procedure, and the surgical room characteristics has a crucial impact on OR time and effectiveness.

Door To Detorsion Time Determines Testicular Survival.

OBJECTIVE: To determine the importance of the duration of in-hospital management of patients with testicular torsion for testes survival. The time from onset of symptoms until surgery is a well-known factor determining testicular survival but there is no data regarding the contribution of in-hospital management duration to testicular survival. Unlike the time from onset of symptoms until seeking medical attention, the time from registration to the emergency department (ED) to the time of detorsion-"Door To Detorsion time" (DTD) is dependent on medical providers and should be minimized. MATERIALS AND METHODS: Data was retrieved on all patients who underwent surgery for testicular torsion in 1994-2014 (N = 219). We used multivariable logistic regression analysis to examine independent association between DTD time or duration of symptoms to testicular survival. RESULTS: Median DTD time was 135 minutes (range 23-546). Among patients with a viable testis, median DTD time was 107 minutes (range 35-381) compared to 160 minutes (range 23-546) among patients with a nonviable testis (P <.001). Logistic regression models showed that both DTD time (P = .04) and duration of symptoms (P <.001) are independent factors associated with testicular survival. Adjusted odds ratio was 1.0048 for a nonviable testis for every minute of delayed management in the ED (P = .04). Results suggest that every 10 minutes of delay in the ED increases the chance of having a nonviable testis in exploration by 4.8%. CONCLUSION: DTD is an independent factor predicting testicular survival. Institutional efforts should be made to decrease duration of DTD. DTD should be considered as a measure for quality of care.

Will Stone Density Stop Being a Key Factor in Endourology? The Impact of Stone Density on Laser Time Using Lumenis Laser p120w and Standard 20 W Laser: A Comparative Study.

Introduction and Objectives: Ureteroscopy is the gold standard for most urinary tract calculi. Our institute recently incorporated a powerful 120 W holmium laser machine integrating innovative technology (Lumenis® MOSES PulseTM120H Holmium:YAG laser; Lumenis Ltd.). In this retrospective comparative study, we evaluated the influence of stone density on laser dusting time in a high-power 120 W laser machine vs a standard 20 W machine (Dornier Medilas® H20 Holmium:YAG laser; Dornier Ltd.) Methods: We conducted a retrospective review of medical records of patients who underwent ureteroscopy during the years 2013-2018 for a solitary stone. Stone and clinical characteristics, among other parameters, have been evaluated, including the total laser time until complete stone dusting. Results: Among 631 eligible patients, 462 were treated with a 20 W standard laser and 169 patients with a p120w laser machine. Overall laser time was less than half with p120w laser vs d20w (195 seconds vs 397.14 seconds, p-value <0.001). Multivariate regression demonstrated 234.91 seconds shorter laser time with a p120w laser while controlling confounders such as stone volume, hydronephrosis, and location (p value <0.0001). This pattern was demonstrated in all stone densities. The association between laser dusting time per stone volume and stone density demonstrated relatively constant laser time when using p120w laser, even for hard stones. When the standard 20 W laser was used, laser time was longer in each stone density. Moreover, a stone density of 1164 HU and more demonstrated an upward shift of laser time to stone density curve in standard d20w laser group only. Conclusions: Time to complete stone dusting using p120w laser is extremely shorter, approximately half, comparing with the standard 20 W laser. This pattern is robust and even exponential when evaluating laser time per stone density, especially in hard stones. A new horizon of powerful innovative laser technology will enable to improve endourology practice and patients' care.

Is emergency percutaneous antegrade drainage of the upper urinary tract useful for future percutaneous nephrolithotomy access?

PURPOSE: To compare percutaneous nephrolithotomy (PCNL) operations between patients with a preoperative nephrostomy tube and patients that the renal access was obtained at the time of the surgery. MATERIALS AND METHODS: We retrospectively evaluated PCNL cases. Patients were divided into two groups. Group 1 - a non-nephrostomy tube (percutaneous nephrostomy, PCN) group and Group 2 - patients with a PCN placed before the procedure. All preoperatively placed PCN's were performed in emergency situations by interventional radiologists (IR). Complications were classified according to the Clavien-Dindo classification. We compared stone characteristics, operation time, complications, efficacy and PCN usability at surgery. RESULTS: Five hundred twenty-seven patients who were submitted to PCNL for renal stones were included in the study. In 73 patients (13.9%) the PCNs were placed before the surgery. Patients and stone characteristics, mean operative time (p=0.830), complications (p=0.859) and stone-free rates (93.0%) were similar between the groups. There was a trend toward higher complication rates in Group 1, but the difference was not statistically significant. Only 21 (29.0%) of preoperatively placed PCNs were used during PCNL for establishing a tract. The reasons for not using PCN tract were: pelvic or infundibular insertion (30.0%) and suboptimal anatomic location (70.0%). CONCLUSIONS: Preoperative emergency inserted PCNs by IR usage rates were low during PCNL. Its placement neither affects the incidence of complications nor affects the operation time and outcomes. As such, when emergency renal drainage is indicated, the need for a future definitive PCNL should not influence the decision about the modality of renal drainage.

"Stoneless" or Negative Ureteroscopy: A Reality in the Endourologic Routine or Avoidable Source of Frustration? Estimating the Risk Factors for a Negative Ureteroscopy.

INTRODUCTION: A "Negative" ureteroscopy (URS) is defined as a URS in which no stone is found during the procedure. It may occur when the stone has already been passed spontaneously or when it is located outside the collecting system. The aim of the study was to outline risk factors for Negative-URS. MATERIALS AND METHODS: We retrospectively analyzed the possible risk factors for Negative-URS from a database of 341 URS cases. In every case where presumptive ureteral stone was not found, a formal nephroscopy as well as a whole collecting system revision was completed. The Negative-URS group was compared with the non-Negative-URS group, in terms of patient and stone characteristics. RESULTS: The database of 341 URS cases included 448 different stone instances, of which 17 (3.8%) were negative and 431 (96.2%) were therapeutic. There was no statistical significant difference between the two groups concerning age, body mass index, stone location in the ureter, stone laterality, and whether the patient was prestented. The stepwise multiple logistic regression revealed three important risk factors, namely CT stone surface area (p < 0.0001), radiopacity of the stone at kidney, ureter, and bladder radiograph (KUB; p = 0.0004), and gender (p = 0.0011) with an area under the curve of 0.91. Women were found to have more possibilities to have a negative procedure by four- to sevenfold than men depending on the model. A nonradio-opaque stone at KUB is more likely to be correlated with a Negative-URS by 9.5- to 11-fold more than a radiopaque stone at KUB. For each increase of 1 U in CT stone surface area, there is an increase of 10%-12% to be non-negative. CONCLUSIONS: Female gender, a nonradio-opaque stone at KUB, and a smaller stone surface were statistically significantly different in the Negative-URS population.

[PERCUTANEOUS TREATMENT OF SMALL RENAL TUMORS BY THERMAL ABLATION].

INTRODUCTION: Kidney cancer accounts for approximately 2-3 % of all types of cancers. Renal tumors prevalence and especially the prevalence of small renal tumors, is on the rise. About half of the tumors currently diagnosed are smaller than 4 cm. Minimally invasive methods of radiofrequency ablation technology were recently developed for the treatment of small renal tumors and are characterized by reducing the surgical and anesthetic risk. The ablation is performed with a percutaneous approach guided by ultrasound, CT or MRI. We reviewed the results of this treatment. METHODS: A total of 75 patients with a mean age of 69.5 years (27 - 90) were treated using RF during the period 2007-2014. The average tumor diameter was 28.4 mm (11-58 mm); 40 tumors were exophytic and 30 were central. Monitoring protocol after treatment included imaging after 1, 3, 6, 12 months subsequent to treatment and later annually; median follow-up time was 21 months (1 - 97). RESULTS: Evidence of tumor recurrence was observed in 9 patients (11.4%); 8 were treated successfully by another RF session. Cases in which recurrence was observed were characterized by a tumor larger than 30 mm (5/9) and adjacent to renal cysts (3/9); 5 of the lesions were central (endophytic) (P=0.5). One patient died due to metastatic RCC and a metastatic disease developed in two additional patients who died of other causes. CONCLUSIONS: It is possible to destroy most of the small renal tumors by RF ablation. When the tumor size is up to 30 mm, a 94% long-term cure may be reached. In the event of renewed growth of the tumor, the treatment can be repeated with good results. In light of short-term experience, it is recommended to limit this treatment to older patients, with a short life expectancy or when anesthetic risks prohibit surgery.

Interobserver Reliability and Reproducibility of the Clinical Research Office of the Endourological Society Nomogram in Predicting Percutaneous Nephrolithotomy Results.

OBJECTIVE: To assess interobserver reliability and reproducibility of the Clinical Research Office of the Endourological Society (CROES) nephrolithometric nomogram. PATIENTS AND METHODS: Preoperative data and postoperative outcomes of 100 consecutive patients who underwent percutaneous nephrolithotomy were obtained. Patients' data were reviewed separately by 4 independent urologists of different academic level: an experienced attending endourologist, a graduated fellow, a young fellow, and a resident. Each rater adjusted a CROES score in all 100 patients. Interobserver reliability was analyzed by assessing intraclass correlation (ICC) and kappa coefficient among and between all different raters. RESULTS: Assessment of interobserver reliability showed good or excellent agreement among all raters. Moderate agreement was only found between the raters for the "presence of staghorn" score. ICCs among all raters expressed excellent levels for each independent CROES parameter and reached great statistical significance. The highest correlation was noticed for "stone burden" in contrast to "presence of staghorn" parameter that showed the lowest. ICC for the final CROES score revealed good to excellent agreement among all raters and all pairs of raters. CONCLUSION: CROES nephrolithometry is a reproducible nomogram. Reproducible results were obtained within a single institution by multiple reviewers of varying experience within a short period of time after undergoing standardized training.

Surgical experience gained during an endourology fellowship program may affect fluoroscopy time during ureterorenoscopy.

The purpose of this study was to identify parameters that affect fluoroscopy time during ureteroscopy or retrograde intrarenal surgery (RIRS) and to evaluate the potential role of surgical experience gained during a fellowship program in decreasing radiation exposure. A database of patients who underwent ureteroscopy or RIRS was evaluated. Procedures were performed either by an experienced Endourologist (surgeon A) or by an Endourology fellow. Operations performed by the fellow were further divided to them performed during fellow's 1st year of training (surgeon F1) and 2nd year of training (surgeon F2). The association between fluoroscopy time and several factors was evaluated. Eighteen (19.6%) procedures were performed by surgeon F1, 13 (14.1%) by surgeon F2 and 61 (66.3%) cases were performed by surgeon A. Fluoroscopy time was significantly higher in cases performed by surgeon F1 compared to surgeon F2 (p=0.025) and A (p=0.001). However, there was no difference between surgeon F2 and A (p=0.969). There was significant association between fluoroscopy time and obesity (p=0.023), stone size (p=0.009), surgical experience (p=0.001), procedure duration (p<0.001) and the insertion of a postoperative double-J stent (p<0.001). Multivariate analysis showed that procedure duration (p=0.003), postoperative stenting (p=0.009) and surgeon's experience (p<0.001) were all significant independent predictors of increased fluoroscopy time. Fluoroscopy time may widely vary during ureteroscopy and RIRS. Procedure duration, the insertion of a postoperative double-J stent and surgical experience are all independent predictors of increased fluoroscopy time.