Dietary Oxalate Loading Impacts Monocyte Metabolism and Inflammatory Signaling in Humans.

Diet has been associated with several metabolic diseases and may impact immunity. Increased consumption of meals with high oxalate content may stimulate urinary calcium oxalate (CaOx) crystals, which are precursors to CaOx kidney stones. We previously reported that CaOx stone formers have decreased monocyte cellular bioenergetics compared to healthy participants and oxalate reduces monocyte metabolism and redox status in vitro. The purpose of this study was to investigate whether dietary oxalate loading impacts monocyte cellular bioenergetics, mitochondrial complex activity, and inflammatory signaling in humans. Healthy participants (n = 40; 31.1 ± 1.3 years) with a BMI of 24.9 ± 0.6 kg/m2 consumed a controlled low oxalate diet for 3 days before drinking a blended preparation of fruits and vegetables containing a large amount of oxalate. Blood and urine were collected before (pre-oxalate) and for 5 h after the oxalate load to assess urinary oxalate levels, monocyte cellular bioenergetics and mitochondrial complex activity, and plasma cytokine/chemokine levels. Urinary oxalate levels significantly increased in post-oxalate samples compared to pre-oxalate samples. Monocyte cellular bioenergetics, mitochondrial complex I activity, and plasma cytokine and chemokine levels were altered to varying degrees within the study cohort. We demonstrate for the first time that dietary oxalate loading may impact monocyte metabolism and immune response in a cohort of healthy adults, but these response are variable. Further studies are warranted to understand oxalate mediated mechanisms on circulating monocytes and how this potentially influences CaOx kidney stone formation. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT03877276.

Internal validation and decision curve analysis of a preoperative nomogram predicting a postoperative complication in pheochromocytoma surgery: An international study.

OBJECTIVES: To develop a preoperative nomogram that would predict the risk of a postoperative complication for pheochromocytoma patients undergoing adrenalectomy using an international database. METHODS: We retrospectively analyzed preoperative variables and postoperative outcomes in patients who underwent adrenalectomy for pheochromocytoma in three institutions from 2000 to 2017. Internal validation of a generated nomogram was carried out with receiver operating characteristics, calibration plots, and decision curve analyses. RESULTS: A total of 153 patients who had undergone 166 adrenalectomies were included in the study. Overall, post-adrenalectomy complications were seen in 30% of patients, whereas 9.6% of patients sustained a Clavien ≥3a complication. Independent predictors of a complication were a history of hypertension, body mass index, tumor size, and Charlson Comorbidity Index score. On internal validation, the multivariable model generated a nomogram that predicted a postoperative complication or clinically hemodynamic event with an area under the curve of 0.86, showed good calibration and had an overall net benefit. CONCLUSIONS: An internally validated nomogram combining body mass index, Charlson Comorbidity Index score and tumor size can predict the probability of a post-adrenalectomy complication in those with and without hypertension. The model, the first of its kind in pheochromocytoma surgery, identifies patients at risk of a postoperative complication at the time of their presentation with pheochromocytoma.

MRI/US fusion-guided prostate biopsy allows for equivalent cancer detection with significantly fewer needle cores in biopsy-naive men.

PURPOSE: We aimed to investigate the efficiency and cancer detection of magnetic resonance imaging (MRI) / ultrasonography (US) fusion-guided prostate biopsy in a cohort of biopsy-naive men compared with standard-of-care systematic extended sextant transrectal ultrasonography (TRUS)-guided biopsy. METHODS: From 2014 to 2016, 72 biopsy-naive men referred for initial prostate cancer evaluation who underwent MRI of the prostate were prospectively evaluated. Retrospective review was performed on 69 patients with lesions suspicious for malignancy who underwent MRI/US fusion-guided biopsy in addition to systematic extended sextant biopsy. Biometric, imaging, and pathology data from both the MRI-targeted biopsies and systematic biopsies were analyzed and compared. RESULTS: There were no significant differences in overall prostate cancer detection when comparing MRI-targeted biopsies to standard systematic biopsies (P = 0.39). Furthermore, there were no significant differences in the distribution of severity of cancers based on grade groups in cases with cancer detection (P = 0.68). However, significantly fewer needle cores were taken during the MRI/US fusion-guided biopsy compared with systematic biopsy (63% less cores sampled, P < 0.001) CONCLUSION: In biopsy-naive men, MRI/US fusion-guided prostate biopsy offers equal prostate cancer detection compared with systematic TRUS-guided biopsy with significantly fewer tissue cores using the targeted technique. This approach can potentially reduce morbidity in the future if used instead of systematic biopsy without sacrificing the ability to detect prostate cancer, particularly in cases with higher grade disease.

Analysis of cost of component replacement versus entire device replacement during artificial urinary sphincter revision surgery.

AIM: To identify the costs of replacing an entire malfunctioning AUS device versus an individual component at the time of device malfunction. METHODS: Decision analysis was performed by analyzing the costs associated with revising a malfunctioning artificial urinary sphincter using one of two techniques: either individual or entire device replacement. Costs were determined by including actual institutional costs. Model assumptions were based on a summary of published literature and were created based on a time horizon of 0-5 years since the original, primary AUS was placed, and models were created for malfunction of each individual component. Sensitivity analysis was done adjusting for costs of the device and failure rates. RESULTS: Total costs to replace an individual component were $8330 for the pump, $7611 for the cuff, and $5599 for the balloon, while entire device replacement cost $15 069. Over a 5-year time horizon the cost per patient for replacement of a balloon, pump, or cuff were $14 407, $17 491, and $15 212, respectively, versus $18 001 if the entire device was replaced. To be less costly to replace the entire device, balloon, pump, and cuff failure rates would need to be >55%, >25%, or >37.5% during the first 2 years after placement. CONCLUSION: In the event of failure of the artificial urinary sphincter, cost analysis demonstrates that removal and replacement of the entire device is more expensive than replacement of a malfunctioning component at any point up to 5 years after initial AUS placement.

Oxalate induces mitochondrial dysfunction and disrupts redox homeostasis in a human monocyte derived cell line.

Monocytes/macrophages are thought to be recruited to the renal interstitium during calcium oxalate (CaOx) kidney stone disease for crystal clearance. Mitochondria play an important role in monocyte function during the immune response. We recently determined that monocytes in patients with CaOx kidney stones have decreased mitochondrial function compared to healthy subjects. The objective of this study was to determine whether oxalate, a major constituent found in CaOx kidney stones, alters cell viability, mitochondrial function, and redox homeostasis in THP-1 cells, a human derived monocyte cell line. THP-1 cells were treated with varying concentrations of CaOx crystals (insoluble form) or sodium oxalate (NaOx; soluble form) for 24h. In addition, the effect of calcium phosphate (CaP) and cystine crystals was tested. CaOx crystals decreased cell viability and induced mitochondrial dysfunction and redox imbalance in THP-1 cells compared to control cells. However, NaOx only caused mitochondrial damage and redox imbalance in THP-1 cells. In contrast, both CaP and cystine crystals did not affect THP-1 cells. Separate experiments showed that elevated oxalate also induced mitochondrial dysfunction in primary monocytes from healthy subjects. These findings suggest that oxalate may play an important role in monocyte mitochondrial dysfunction in CaOx kidney stone disease.

Feasibility of Intracorporeal Robotic-Assisted Laparoscopic Appendiceal Interposition for Ureteral Stricture Disease: A Case Report.

OBJECTIVE: To describe a robotic-assisted laparoscopic (RAL) technique for using the appendix to repair ureteral stricture disease MATERIALS AND METHODS: A case of a patient presenting with a 5-cm obliterative right ureteral stricture was reviewed, and surgical technique, complications, and outcomes were reported. RESULTS: Our patient developed a right-sided 5-cm obliterative ureteral stricture secondary to recurrent stone disease and pyelonephritis. He underwent an uncomplicated RAL repair of his stricture with interposition of the appendix between the 2 segments of ureter. Operative time was just over 6 hours, blood loss was minimal, and there were no complications. A 10-month follow-up showed resolution of hydronephrosis with no flank pain. CONCLUSION: We report our initial experience with this procedure and believe that RAL appendiceal interposition for ureteral stricture disease presents an excellent option for reconstruction.

Ureteral Embolization to Prevent Thrombotic Obstruction of Nephrostomy Catheters in the Context of Refractory Hemorrhagic Radiation Cystitis with Severe Vesicoureteral Reflux.

We present a case of refractory hemorrhagic radiation cystitis in a patient who failed conservative management and was unable to undergo operative urinary diversion secondary to multiple comorbidities. His management was complicated by recurrent obstruction of his nephrostomy catheters due to marked ureteral thrombus formation from blood refluxing into the ureters from the urinary bladder. We were successful in treating his condition by occluding his distal ureters with a combination of embolization coils and glue to prevent the reflux of blood in order to allow his nephrostomy catheters to function properly.

Variation in the intensity of hematuria evaluation: a target for primary care quality improvement.

BACKGROUND: Hematuria is a common clinical finding and represents the most frequent presenting sign of bladder cancer. The American Urological Association recommends cystoscopy and abdomino-pelvic imaging for patients aged more than 35 years. Nonetheless, less than half of patients presenting with hematuria undergo proper evaluation. We sought to identify clinical and nonclinical factors associated with evaluation of persons with newly diagnosed hematuria. METHODS: We performed a retrospective cohort study, using claims data and laboratory values. The primary exposure was practice site, as a surrogate for nonclinical, potentially modifiable sources of variation. Primary outcomes were cystoscopy or abdomino-pelvic imaging within 180 days after hematuria diagnosis. We modeled the association between clinical and nonclinical factors and appropriate hematuria evaluation. RESULTS: We identified 2455 primary care patients aged 40 years or more and diagnosed with hematuria between 2004 and 2012 in the absence of other explanatory diagnosis; 13.7% of patients underwent cystoscopy within 180 days. Multivariate logistic regression revealed significant variation between those who did and did not undergo evaluation in age, gender, and anticoagulant use (P < .001, P = .036, P = .028, respectively). Addition of practice site improved the predictive discrimination of each model (P < .001). Evaluation was associated with a higher rates of genitourinary neoplasia diagnosis. CONCLUSIONS: Patients with hematuria rarely underwent complete evaluation. Although established risk factors for malignancy were associated with increasing use of diagnostic testing, factors unassociated with risk, such as practice site, also accounted for significant variation. Inconsistency across practice sites is undesirable and may be amenable to quality improvement interventions.