Vitamin D Repletion in Kidney Stone Formers: A Randomized Controlled Trial.

PURPOSE: Vitamin D deficiency is often detected during metabolic evaluation in the nephrolithiasis population. Multiple vitamin D repletion protocols exist, although their differing impact on urinary stone formation risk factors is unclear. MATERIALS AND METHODS: Patients with a history of calcium stones and vitamin D deficiency (less than 30 ng/ml) were randomized to receive either 1,000 IU daily or 50,000 IU weekly of vitamin D supplementation for 6 weeks. Patients completed a pretreatment and posttreatment serum vitamin D level evaluation and 24-hour urine collections to assess the response and any changes in urine stone formation risk parameters. RESULTS: A total of 21 patients completed the study, including 8 who received 1,000 IU daily and 13 who received 50,000 IU weekly. The 50,000 IU weekly group showed a significant increase in median serum vitamin D levels of 23 ng/ml (135%, p <0.01), while the 1,000 IU daily group showed a nonsignificant median increase of 9 ng/ml (49%, p = 0.12). Post-repletion 24-hour urine analysis demonstrated no significant change in urine calcium between the groups, including a median change of -11 mg (IQR -143-29) in patients receiving 1,000 IU and -16 mg (IQR -42-66) in those receiving 50,000 IU. Between the groups there was no significant difference in the supersaturation of calcium oxalate or calcium phosphate. CONCLUSIONS: High dose and low dose vitamin D repletion had no effect on urine calcium excretion or the supersaturation of calcium salts in known stone formers. The higher dosing regimen, which had superior repletion, may be the optimal protocol in patients with vitamin D deficiency.

Defining the Rate of Primary Ureteroscopic Failure in Unstented Patients: A Multi-Institutional Study.

PURPOSE: Primary ureteroscopic intervention for kidney or ureteral stones occasionally encounters difficulty with passage of the ureteroscope in the initial procedure. These patients require a second procedure after stenting. We aim to define the contemporary failure rate of primary ureteroscopy (URS) and identify predictive factors that necessitate prestenting. This will assist in preoperative patient counseling, informed consent, and clinical decision-making. MATERIALS AND METHODS: We conducted a multi-institutional retrospective review of 535 unstented patients undergoing primary URS from August 2011 to August 2013. The primary outcome was gaining access to the unstented ureter. RESULTS: The failure rate for accessing the unstented ureter was 7.7% (41/535). The median age of females with primary ureteroscopic failure was significantly lower than in females who had successful ureteroscopic access (34 vs 52 years; p = 0.0041). There was no difference in the median age of males with access vs failure (58 vs 57 years; p = 0.3683). Proximal ureteral stones had the highest failure rate for ureteral access at 18.28% (p = 0.006). On multivariable logistic regression, proximal ureteral stone location remained a significant predictor of failure when compared to renal stones (odds ratio [OR] 3.14, p = 0.006). When including only ureteral stones in the multivariable analysis, stone location in the proximal ureter compared to the distal ureter remained the only significant predictor of access failure (OR 0.24, p = 0.015). CONCLUSIONS: A low overall rate of ureteral access failure in unstented patients is shown. Young female patients and proximal ureteral stones were less likely to be accessed primarily. This study provides information that will help urologists counsel their patients preoperatively regarding their likelihood of failing primary URS necessitating a second procedure. This will also help the patient to make an informed decision during the consent process and may guide urologists on selective prestenting in higher risk patients.

Blunt force trauma as a rare mechanism for chyluria.

Chyluria is an uncommon clinical entity outside of the tropics. We present a rare case of blunt force trauma leading to the formation of a lymphorenal fistula. This was successfully managed via conservative endoscopic and dietary treatment.

The Role of Prophylactic Antibiotics After Minimally Invasive Pyeloplasty With Ureteral Stent Placement in Children.

OBJECTIVE: To determine whether children discharged with prophylactic antibiotics following laparoscopic pyeloplasty with indwelling ureteral stent have a decrease risk of postoperative urinary tract infections (UTIs) compared to those discharged without antibiotics. MATERIALS AND METHODS: A retrospective review of all minimally invasive pyeloplasties performed at our institution from January 2009 to March 2015 was conducted. Patients were discharged home with or without daily prophylactic-dose antibiotics continued until 3 days after ureteral stent removal per surgeon preference. The primary outcome was incidence of culture-positive UTI. Secondary outcomes included bacteriuria at time of stent removal and adverse events associated with extended antibiotic therapy. RESULTS: Of 163 pyeloplasties (106 robotic and 57 pure laparoscopic) performed over the study period, 126 patients were discharged on prophylactic antibiotics whereas 37 patients were discharged without prophylaxis. Groups were different with respect to median age (7.1 vs 12.0 years, P = .03) and median duration of ureteral stent (35 days vs 28 days, P = .02). The incidence of culture-positive UTI between the time of discharge and stent removal was comparably low between groups; 2/126 (1.6%) in the prophylaxis group and 1/37 (2.7%) in the group not on prophylaxis. At time of stent removal, perioperative urine culture was positive in 2/20 (10.0 %) patients who received prophylactic antibiotics and in 1/25 (4.0%) patients who did not (P = .54). CONCLUSION: The administration of extended prophylactic antibiotics showed no significant impact on the rate of UTI following minimally invasive pyeloplasty.

Divergence between dietary folate intake and concentrations in the serum and red blood cells of aging males in the United States.

BACKGROUND & AIMS: As part of a broader study examining the relationship between serum folate concentrations and prostate cancer progression, we determined if there are age related changes in serum folate concentration compared to folate intake in the U.S. male population. METHODS: Weighted data from the 2007-2008 and 2009-2010 NHANES databases was analyzed. A subpopulation of male participants was selected who were older than one year of age, had completed two days of dietary recall including supplement usage, and had fasted for at least 4 h prior to having their serum folate measured. Total dietary folate equivalent (DFE) intake (mcg) represented the combination of all natural food folate and folic acid from fortification and dietary supplements. Geometric means of serum folate (nM), red blood cell (RBC) folate (nM), and DFE intake were calculated for nine consecutive age groups, with each group generally representing a 10 year span. Analysis was then focused on males older than 20 years of age. RESULTS: A total of 19,142 subjects were in the initial NHANES population, which represented over 294 million people within the United States. Applying our inclusion criteria created a final subpopulation size of 3775. Subsequent analysis of the age groups for all males older than 20 years found the following: The mean serum folate (nM) with 95% CI levels ranged from 28.2 (26.6, 29.9) to 55.1 (47.5, 63.9). RBC folate (nM) concentrations with 95% CI levels without any fasting exclusions ranged from 795.6 (741.5, 853.7) to 1038.4 (910.7, 1184.2). Serum and RBC folate concentrations were significantly higher with age across these age groups (p < 0.001). However, the mean total daily DFE intake did not significantly differ ranging from 640.4 (574.7, 713.7) to 720.2 (665, 780) mcg, (p = 0.373). Serum folate concentrations in men with total daily DFE intake of at least 1000 mcg increased more significantly with increasing age than serum folate concentrations in men with less than 400 mcg of total daily DFE intake (p < 0.001). There was a similar trend with the RBC folate concentrations (p = 0.054). CONCLUSIONS: We observed higher serum and RBC folate concentrations and a divergence between dietary folate intake and these folate concentrations in older males. This phenomenon was evident at total DFE intakes that were significantly less than the 1000 mcg tolerable upper intake level currently recommended by the Institute of Medicine.

Bipolar Transurethral Incision of Bladder Neck Stenoses with Mitomycin C Injection.

Introduction. To determine the efficacy of bipolar transurethral incision with mitomycin C (MMC) injection for the treatment of refractory bladder neck stenosis (BNS). Materials and Methods. Patients who underwent bipolar transurethral incision of BNS (TUIBNS) with MMC injection at our institution from 2013 to 2014 were retrospectively reviewed. A total of 2 mg of 40% mitomycin C solution was injected in four quadrants of the treated BNS. Treatment failure was defined as the need for subsequent intervention. Results. Thirteen patients underwent 17 bipolar TUIBNS with MMC injection. Twelve (92%) patients had failed a mean of 2.2 ± 1.1 prior endoscopic procedures. Median follow-up was 16.5 months (IQR: 14-18.4 months). Initial success was 62%; five (38%) patients had a recurrence with a median time to recurrence of 7.3 months. Four patients underwent a repeat procedure, 2 (50%) of which failed. Overall success was achieved in 77% (10/13) of patients after a mean of 1.3 ± 0.5 procedures. BNS recurrence was not significantly associated with history of pelvic radiation (33% versus 43%, p = 0.9). There were no serious adverse events. Conclusions. Bipolar TUIBNS with MMC injection was comparable in efficacy to previously reported techniques and did not result in any serious adverse events.

Ureteral obstruction following partial nephrectomy: can it be caused by fibrin glue?

Fibrin sealants are widely used during partial nephrectomy, however reports regarding the potential complications associated with their use are limited. We present the case of a 67-year-old male who developed delayed ureteral obstruction without hydronephrosis following partial nephrectomy in a solitary kidney. We hypothesize that the obstruction and absence of hydronephrosis were caused by extrinsic compression and subsequent inflammation due to the fibrin glue. Our report underscores the importance of a high index of suspicion for obstruction when acute kidney injury occurs following partial nephrectomy when fibrin glue is used, even in the absence of collecting system dilatation.

Calyceal diverticulum with a large extra-renal extension in a 5-year-old child.

Calyceal diverticula are rare findings in children, often identified due to symptomatic presentation. We present the unique case of an incidentally found calyceal diverticula in a 5-year-old girl with a large extra-renal component, which was successfully excised in a robot-assisted laparoscopic procedure that was without complication.

Novel nuclear localization of fatty acid synthase correlates with prostate cancer aggressiveness.

Fatty acid synthase is up-regulated in a variety of cancers, including prostate cancer. Up-regulation of fatty acid synthase not only increases production of fatty acids in tumors but also contributes to the transformed phenotype by conferring growth and survival advantages. In addition, increased fatty acid synthase expression in prostate cancer correlates with poor prognosis, although the mechanism(s) by which this occurs are not completely understood. Because fatty acid synthase is expressed at low levels in normal cells, it is currently a major target for anticancer drug design. Fatty acid synthase is normally found in the cytosol; however, we have discovered that it also localizes to the nucleus in a subset of prostate cancer cells. Analysis of the fatty acid synthase protein sequence indicated the presence of a nuclear localization signal, and subcellular fractionation of LNCaP prostate cancer cells, as well as immunofluorescent confocal microscopy of patient prostate tumor tissue and LNCaPs confirmed nuclear localization of this protein. Finally, immunohistochemical analysis of prostate cancer tissue indicated that nuclear localization of fatty acid synthase correlates with Gleason grade, implicating a potentially novel role in prostate cancer progression. Possible clinical implications include improving the accuracy of prostate biopsies in the diagnosis of low- versus intermediate-risk prostate cancer and the uncovering of novel metabolic pathways for the therapeutic targeting of androgen-independent prostate cancer.

Opposing roles of folate in prostate cancer.

The US diet has been fortified with folic acid to prevent neural tube defects since 1998. The Physician Data Queries from the National Cancer Institute describe folate as protective against prostate cancer, whereas its synthetic analog, folic acid, is considered to increase prostate cancer risk when taken at levels easily achievable by eating fortified food or taking over-the-counter supplements. We review the present literature to examine the effects of folate and folic acid on prostate cancer, help interpret previous epidemiologic data, and provide clarification regarding the apparently opposing roles of folate for patients with prostate cancer. A literature search was conducted in Medline to identify studies investigating the effect of nutrition and specifically folate and folic acid on prostate carcinogenesis and progression. In addition, the National Health and Nutrition Examination Survey database was analyzed for trends in serum folate levels before and after mandatory fortification. Folate likely plays a dual role in prostate carcinogenesis. There remains conflicting epidemiologic evidence regarding folate and prostate cancer risk; however, there is growing experimental evidence that higher circulating folate levels can contribute to prostate cancer progression. Further research is needed to clarify these complex relationships.