Long-Term Follow-Up of Yearly Replaced Double Internal Stents for Extrinsic Malignant Ureteral Obstruction.

Introduction: To assess long-term outcomes of double internal stents (DIS) for the relief of external malignant ureteral obstruction (MUO). Materials and Methods: DIS (7F each; 12-month indwelling time) were inserted under general anesthesia in 62 consecutive patients (75 renal units) with MUO during 2007-2018. Surveillance was performed every 3 months, and stents were exchanged routinely every year. The need for permanent stent retrieval was considered stent failure. Maintenance of stent patency and disease-specific survival (DSS) were estimated (Kaplan-Meier). Risk factors were also assessed (univariate and multivariable Cox regression analyses). Results: The median follow-up was 27 months (interquartile range [IQR] 20-27). The most frequent tumors causing obstruction were colorectal and ovarian cancers. Six patients (10%) had stent failure caused by sepsis, creatinine elevation, or hematuria. The average time to failure was 15 months (range 1-27). A history of radiation and an estimated glomerular filtration rate (eGFR) ≤45 mL/(min/1.73 m2) were associated with stent failure (p = 0.038 and p = 0.001, respectively). Thirty-nine patients died with a median DSS of 21 months (IQR 8.6-not reached). Multivariate analysis identified eGFR ≤60 mL/(min/1.73 m2) (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.1-4.2, p = 0.02) and need for balloon dilation (HR 2.1, 95% CI 1.1-4.1, p = 0.02) as independent predictors for disease-related mortality. Twenty-six patients (42%) had stent-related complications, for example, irritative symptoms, hematuria, and infections, of whom only two failed. Conclusions: One-year indwelling DIS provide effective long-term relief of MUO and represent a simple and effective alternative to other methods of urinary diversion. They avoid the need for external tubes and contribute to improved patient satisfaction.

Assessment of bilateral supine and prone tubeless percutaneous nephrolithotomy.

INTRODUCTION: To assess the outcome of same-session bilateral tubeless percutaneous nephrolithotomy (BPCNL) in supine and prone positions and to compare them to unilateral tubeless PCNL (UPCNL). MATERIALS AND METHODS: Consecutive PCNL patients treated at two institutions between 2006-2016 were analyzed. Tubeless BPCNL was performed when indicated. RESULTS: Fifty-eight patients underwent BPCNLs [30 supine (SBPCNL) and 28 prone (PBPCNL)], while 1395 patients underwent UPCNLs. Demographics and baseline data were similar for all groups (p > 0.05). SBPCNL had a longer operating time (124 +/- 38 minutes versus 105 +/- 36 minutes; p = 0.49) and a significantly longer hospital stay (3.6 +/- 1.9 versus 2.4 +/- 1.3 days, respectively; p = 0.019) in comparison to PBPCNL. Seven planned BPCNLs were converted to UPCNL, resulting in a BPCNL success rate of 58/65 (89%). When compared to UPCNL, BPCNL patients had a significantly increased postoperative creatinine level (0.74 +/- 0.3 versus -0.04 +/- 0.8 g/dL; p = 0.07E-7), a decreased postoperative hemoglobin level (2 +/- 1.1 versus 1.4 +/- 1.7 mg/dL; p = 0.026), a higher blood transfusion rate (9% versus 2%; p = 0.023), and a longer hospital stay (3 +/- 1.7 versus 1.6 +/- 1.7 days; p = 0.001E-4). Stone-free and overall complication rates were similar for both groups. CONCLUSION: BPCNL can be routinely offered to patients with a bilateral indication. BPCNL is associated with higher blood transfusion rates and longer hospital stays, but it may spare patients from repeat anesthesia and hospitalization. SBPCNL takes longer to perform than PBCNL, but without clinical ramifications.

Implementation of supine percutaneous nephrolithotomy: a novel position for an old operation.

INTRODUCTION: Supine percutaneous nephrolithotomy (PCNL) has become increasingly widespread during the last 2 decades. The aim of this study was to analyze the transition from prone to mainly supine PCNL in 2 endourologic centers. MATERIAL AND METHODS: We retrospectively analyzed data on 214 consecutive supine PCNLs divided into the first (2011-2013) and last (2014-2016) 3 years of this study. The first 27 cases were also included in a randomized controlled trial (RCT) by comparison with 24 prone PCNLs. We compared the clinical outcome and implementation rate. The surgical team was surveyed for their overall impression of performing supine PCNLs. RESULTS: The RCT revealed a trend toward shorter operative time (138 vs. 150 minutes), anesthesia time (174 vs. 192 minutes) and hospitalization (2.2 vs. 2.6 days) in the supine PCNL group, without statistical significance and similar stone free rates (SFR) as for the prone PCNL group. Implementation of the supine PCNL reached 96% in 3 years. There was a decrease in operative time (110 vs. 154 minutes; P <0.0001), hospital stay (1.5 vs. 2.1 days; P <0.01), blood transfusion (5% vs. 14%; P <0.05) and rate of ancillary procedures (5% vs. 16%; P <0.05) in the last 3 years of the study. SFR remained stable. Both the surgeons and anesthesiologists expressed their unanimous preference for the supine position over the prone position. CONCLUSIONS: Supine PCNLs are easy to implement without a significant learning curve for an experienced endourologist. They can be employed in complex cases and improve surgeon's ergonomics and anesthesiologist's access to the patient.

Upper Calyx Accessibility Through a Lower Calyx Access Is Not Influenced by Morphometric and Clinical Factors in Supine Percutaneous Nephrolithotomy.

OBJECTIVE: To assess whether morphometric and clinical parameters influence accessibility to the upper calyx through a lower calyx tract during supine percutaneous nephrolithotomy (SPCNL). PATIENTS AND METHODS: Data for 114 consecutive SPCNLs performed between June 2014 and March 2016 in an academic medical center were analyzed. Successful approachability was defined as rigid nephroscopic access to the upper calyx introduced through a lower calyx access as attested by direct visualization of the upper calyx papillae and position of the nephroscope on intraoperative pyelography. Demographic, morphometric, and clinical parameters were assessed. Analysis of variance, Fisher's exact, chi-square tests, and univariate and multivariate models were applied. RESULTS: Successful approach was achieved in 94 (82%) patients. In univariate analyses previous kidney operations (p = 0.03), body weight (p = 0.04), and acute lower calyx access to the upper calyx axis angle (p = 0.01E-13) correlated with failed access. Multivariate analyses revealed that an acute angle was the sole independent factor for failed access (odds ratio [OR] 1.4, p < 0.05; confidence interval [95% CI] 1.021, 2.035). Limitations include the inability to objectively determine the mobility of the kidney as a co-factor in successful approachability. CONCLUSIONS: SPCNL offers effective endoscopic accessibility through a lower calyx access. Previous kidney operations and body weight tend to negatively influence this accessibility. An acute angle between the lower calyx and the upper calyx is the single independent factor associated with failed accessibility.

Sulfadiazine-Induced Obstructive Nephropathy Presenting with Upper Urinary Tract Extravasation.

Background: Obstructive nephropathy is an uncommon side effect of sulfadiazine, which is used for the treatment of toxoplasmosis. We present a case of acute renal colic and urine extravasation of a patient shortly after she was started on this medication. Case Presentation: A 31-year-old female presented with acute renal colic 2 weeks after starting treatment with sulfadiazine and pyrimethamine for ocular toxoplasmosis. Results: A noncontrast computed tomography revealed left hydronephrosis and fluid located around the kidney and in the left gutter. There were no urinary stones. Administration of intravenous contrast revealed significant urine extravasation at the level of the ureteropelvic junction. Intravenous contrast injection confirmed that the extravasation consisted of urine leakage at the ureteropelvic junction. Her clinical condition improved with the insertion of an internal stent, which was left in place for 4 weeks. A retrograde pyelography performed at the time of the internal stent removal ruled out persistent extravasation and filling defects in the left upper urinary tract. Considering the clinical circumstances and the imaging results, it appears that this is a first reported case of sulfadiazine-induced obstructive uropathy associated with urine extravasation. Conclusion: Although rare, obstructive uropathy related to sulfadiazine medication should be promptly suspected, diagnosed, and treated. Patients should be instructed to substantially increase their liquid intake while on that medication.