The Circle Nephrostomy Tube: An Attractive Nephrostomy Drainage System Following Complex Percutaneous Nephrolithotomy

Objective To describe our experience with the circle nephrostomy tube (NT) (Cook Medical), a drainage system uniquely designed for use after multiple-access percutaneous nephrolithotomy (PNL). Methods A retrospective review of 1317 consecutive patients undergoing 1599 PNLs at IU Health Methodist Hospital was performed. All multiple access cases utilizing circle NTs were reviewed and analyzed. The method of insertion of circle NT was demonstrated. Results A total of 1843 accesses were obtained in 1599 renal units (RUs): 380 upper pole, 129 interpolar, and 1334 lower pole. Multiple accesses in this series were required in 282 RUs (17.6%). Following multiple-access PNL, circle NTs, Cope loop, and reentry Malecot NTs were inserted in 91 RUs (32.3%), 208 RUs (73.8%), and 31 RUs (11%), respectively. None of the patients who had circle NT experienced clogging, dislodgement, or obstruction of the tube. The cost of circle, Cope loop, and Malecot NTs are 121.73 USD, 95.20 USD, and 81 USD, respectively. Conclusion Circle NTs are easy to insert, secure, cost-effective compared with inserting two NTs. Circle NTs provide excellent drainage and facilitate secondary procedures

Calcium Tartrate Tetrahydrate, Case Report of a Novel Human Kidney Stone

Background: Calcium tartrate tetrahydrate has been reported as the main mineral in urinary stones in rats that have significant tartrate in their diet, but in humans, there has been only one mention of calcium tartrate stones in the form of bladder stone, and that case was in Africa., Case Presentation: Patient is a 34-year-old Caucasian male who presented with typical symptoms of nephrolithiasis. CT abd/pelvis (renal stone protocol) revealed a 2 cm nonobstructing stone of the right renal pelvis. Patient underwent an uncomplicated right percutaneous nephrolithotomy and was noted to be stone free after surgery. Stone analysis was difficult with regard to determining composition, but was finally identified as calcium tartrate tetrahydrate., Conclusion: This was an unusual case, as this is the first recorded case of a calcium tartrate tetrahydrate outside of Africa. This type of stone had only been mainly described in rat models with dl-bitartrate in their diet. Our patient was an otherwise healthy, relatively muscular individual with no obvious source for this stone other than a vitamin and amino acid supplement that he takes regularly that contains l-carnitine (as tartrate) and choline (as bitartrate and citrate). The prevalence of this stone type is presently unknown, as stone analysis laboratories have not had the ability to recognize it. Although a connection between the supplement and stone formation is conjecture at this time, we believe this necessitates further investigation

Sensitivity of Non-Contrast Computed Tomography for Small Renal Calculi with Endoscopy as the Gold Standard

Objectives To compare the sensitivity of non-contrast CT to endoscopy for detection of renal calculi. Imaging modalities for detection of nephrolithiasis have centered on abdominal x-ray (KUB), ultrasound (US), and non-contrast computed tomography (CT). Sensitivities of 58-62% (KUB), 45% (US), and 95-100% (CT) have been previously reported. However, these results have never been correlated with endoscopic findings. Methods Idiopathic calcium oxalate stone formers with symptomatic calculi requiring ureteroscopy (URS) were studied. At the time of surgery, the number and location of all calculi within the kidney were recorded followed by basket retrieval. Each calculus was measured and sent for micro CT and infrared spectrophotometry. All CT scans were reviewed by the same genitourinary radiologist who was blinded to the endoscopic findings. The radiologist reported on the number, location, and size of each calculus. Results 18 renal units were studied in 11 patients. Average time from CT scan to URS was 28.6 days. The mean number of calculi identified per kidney was 9.2±6.1 for endoscopy and 5.9±4.1 for CT (p<0.004). The mean size of total renal calculi (sum of longest stone diameters) per kidney was 22.4±17.1 mm and 18.2±13.2 mm for endoscopy and CT, respectively (p=0.06). Conclusions CT scan underreports the number of renal calculi, probably missing some small stones and unable to distinguish those lying in close proximity to one another. However, the total stone burden seen by CT is, on average, accurate when compared to that found on endoscopic examination

A Survey Regarding Preference in the Management of Bilateral Stone Disease and a Comparison of Clavien Complication Rates in Bilateral vs Unilateral Percutaneous Nephrolithotomy

Objective To discuss complications of simultaneous bilateral percutaneous nephrolithotomy (SB-PCNL) when compared with unilateral percutaneous nephrolithotomy and survey surgeon preference in bilateral stone disease management. Patients and Methods A database of all participating percutaneous nephrolithotomy (PCNL) patients who underwent treatment at Indiana University Health Methodist Hospital within a 10-year period from 2006 to 2015 by a single surgeon (JL) was utilized. Perioperative data, as well as complications, defined according to the Clavien grading system, were recorded. A survey of members of the Endourological Society was performed regarding surgical management in the setting of bilateral stone disease. Results A total of 563 patients were identified over the study period with 129 undergoing SB-PCNL. Overall, SB-PCNL patients had a longer procedure (176.9 vs 115.6 minutes, P <.0001), were more likely to undergo a secondary procedure (73% vs 44, P <.001), and had a longer hospital stay (3.2 vs 2.3 days, P <.001). Notably, there were no differences in the number or the severity of complications between the 2 groups. A total of 153 endourologists completed the survey. Of these endourologists, 58 (38%) performed bilateral PCNL under anesthesia. The top reasons for electing not to perform bilateral PCNLs included the duration of bilateral procedures (53%), bilateral renal injury (48%), and rare performance of bilateral surgery (35%). Conclusion Although the procedure length was longer in the SB-PCNL group, there were similar rates of complications and severity between unilateral PCNL and SB-PCNL. A majority of endourologists surveyed do not perform bilateral PCNL but would perform bilateral ureteroscopy with the duration of the procedure and concern for bilateral renal injury representing the most common reasons

Predictors of Enucleation and Morcellation Time During Holmium Laser Enucleation of the Prostate.

Objective To examine predictors of enucleation and morcellation times within a large cohort of men undergoing holmium laser enucleation of the prostate (HoLEP) for benign prostatic hypertrophy. Materials and Methods Preoperative, perioperative, and postoperative clinical characteristics were available from men treated with HoLEP between 1998 and 2013 at Indiana University Health Methodist Hospital. Stepwise linear regression was performed to determine clinical variables which are associated with enucleation and morcellation times. Results We identified 960 patients who underwent HoLEP. Average (range) enucleation time was 65.7 (11-245) minutes and morcellation time was 19.7 (3-260) minutes. History of anticoagulation was associated with a small decrease in enucleation time (P = .013) whereas increasing HoLEP specimen weight was associated with increasing enucleation time (P <.001). History of intermittent catheterization, urinary tract infections (UTI), presence of dense prostatic tissue (colloquially referred to as “beach balls”), and increasing specimen weight were associated with increasing morcellation time (P <.05 each). Having HoLEP performed by a less experienced urologist was associated with longer enucleation and morcellation times. Conclusion Prostate volume is significantly associated with increased enucleation and morcellation times during HoLEP. Additionally, history of UTI and clean intermittent catheterization (CIC) is associated with modest increases in enucleation and morcellation times. Dense enucleated prostate tissue significantly impacts the ability to morcellate effectively. Increasing surgeon experience can significantly improve both enucleation and morcellation efficiency

Comparison of Perioperative Outcomes Between Holmium Laser Enucleation of the Prostate and Robot-Assisted Simple Prostatectomy

Objectives: To compare perioperative outcomes for patients undergoing holmium laser enucleation of the prostate (HoLEP) and robotic-assisted simple prostatectomy (RSP) for benign prostatic hypertrophy (BPH).Methods: Patient demographics and perioperative outcomes were compared between 600 patients undergoing HoLEP and 32 patients undergoing RSP at two separate academic institutions between 2008 and 2015.Results: Patients undergoing HoLEP and RSP had comparable ages (71 vs 71, p = 0.96) and baseline American Urological Association Symptom Scores (20 vs 24, p = 0.21). There was no difference in mean specimen weight (96 g vs 110 g, p = 0.15). Mean operative time was reduced in the HoLEP cohort (103 minutes vs 274 minutes, p < 0.001). Patients undergoing HoLEP had lesser decreases in hemoglobin, decreased transfusions rates, shorter hospital stays, and decreased mean duration of catheterization. There was no difference in the rate of complications Clavien grade 3 or greater (p = 0.33).Conclusions: HoLEP and RSP are both efficacious treatments for large gland BPH. In expert hands, HoLEP appears to have a favorable perioperative profile. Further studies are necessary to compare long-term efficacy, cost, and learning curve influences, especially as minimally invasive approaches become more widespread

Alkalinizing Agents: A Review of Prescription, Over-the-Counter, and Medical Food Supplements.

Introduction Kidney stones affect 1 in every 11 people in the United States each year. There is a significant high recurrence rate without a stone prevention protocol. Alkali citrate is beneficial in decreasing stone recurrence, but due to the cost and gastrointestinal side effects there is a low adherence rate. This study aims to serve as a review of some of the most commonly used alkalizing over‐ the‐ counter supplements that are advertised to prevent and treat kidney stones. Methods Data was gathered by a comprehensive online literature search and company inquiries for kidney stone prevention supplements. An additional informal poll of the authors selected supplements that are most commonly taken by their patients. A total of eight supplements were evaluated for cost, alkali equivalent provided, dosing and regulatory information. Results Eight of the most commonly used supplements were reviewed with a focus on alkalizing agents. Information reviewed revealed dosing recommendations resulting in decreased citrate alkali equivalents per day compared to prescription‐strength potassium citrate. Cost, peer‐reviewed study results and regulatory data were reviewed, tabulated and analyzed. Cost per alkali equivalent was substantially decreased for each supplement compared to the prescribed drug. All supplements were found to be readily available online. Conclusion Over‐ the‐ counter alkalizing agents are available to patients and may be an appropriate alternative to cost prohibitive potassium citrate when treating urolithiasis patients. Additional testing will be necessary in the future to determine the efficacy of these supplements in the treatment and prevention of urinary stone disease

Uncovering a Novel Stone in 27 Patients: Calcium Tartrate Tetrahydrate

Objective To further analyze calcium tartrate tetrahydrate stones after a recent case report described this novel stone. Prior to this, there was only one previously reported occurrence of this stone in a human. This unusual stone composition is not tested for routinely. True prevalence and possible causes of this stone are unknown. Materials/Methods During the previous case report, micro-CT and Fourier-transform infrared spectroscopy were used to identify a calcium tartrate tetrahydrate stone. This information was applied to urinary stones with previously unidentified compositions in the Mayo Metals laboratory database between 2010 and March 2018. Two additional stones were identified at our institution. Three patients had medical records available for analysis. Results Between 2010 and March 2018, 35 calcium tartrate stones in 25 patients were identified in the Mayo database as well as 2 at our institution (37 stones in 27 patients). Thirty stones were pure calcium tartrate with the remainder having elements of more common stones. The average age was 46.3 (±14.7) with a slightly higher incidence in females (17 vs 10). Of the 3 medical records investigated, all 3 were males (average age 48.7), and each reported consumption of an energy supplement (Spark) routinely. Conclusion The true prevalence of this relatively unknown stone remains unclear and additional investigation is warranted. We believe all stone laboratories should have access to the IR spectra for calcium tartrate tetrahydrate. Attention should be paid to possible causes of this stone, particularly with relation to oral supplements, to aid with future prevention and treatment

The use of a string with a stent for self-removal following ureteroscopy: A safe practice to remain

Abstract objectives: To examine the safety and effectiveness of the use of a stent with a string attached after ureteroscopy (URS) for self-removal of the stent by the patient. Patients and methods: After Institutional Review Board approval, a retrospective chart review was performed concerning patients who underwent URS and received an indwelling stent with or without a string attached to the stent (94 vs 349, respectively). Amongst the string group patients received a single- or a double-arm-stringed stent (31 vs 63, respectively). Statistical analyses included chi-squared and Student’s t-tests. Results: The string group consisted of 94 procedures, in which 59.6% of the patients were male with a mean (SD) age of 50.0 (16.5) years. In the no-string group, 51.3% of the 349 procedures were performed in males and the mean (SD) age was 54.9 (18.1) years. Complication rates were 12.8% in the string group and 14.0% in the no-string group (P = 0.867). In the string group, 17.0% of the patients returned to the Emergency Department, whilst 15.8% of the no-string patients returned (P = 0.753). The complication rate in the single- and double-arm groups were 12.9% and 12.7%, respectively (P > 0.910). Self-removal of stents was successful in 94.7% of patients (89/94). Conclusions: The use of a stent with a string after URS appears safe and effective. Few patients had difficulty removing their stents and complication rates were similar in the groups with and without a string attached to their stents. Single- and double-arm-stringed stents have similar complication rates. Keywords: Ureteric stent, Ambulatory care, Endourology, Urinary tract obstruction, Obstructive uropathy, Outpatient procedur