Introduction:We examined the effect of combined vitamin D and calcium supplementation (VDCS) on urinary calcium excretion and de novo stone formation in vitamin D inadequate (VDI) urolithiasis patients. Methods: We retrospectively reviewed the data of VDI patients (serum 25-hydroxyvitamin D <75 nmol/L) followed at a tertiary stone centre between September 2009 and December 2014. VDI patients with history of urolithiasis, who were placed on VDCS for abnormal bone mineral density or hyperoxaluria, were included. Hypercalciuric patients and patients on thiazide diuretics were excluded. Metabolic stone workup and two 24-hour urine collections were performed before and after VDCS. Results: In total, we included 34 patients, with a mean age of 54.8 years and a mean body mass index of 25.7 kg/m 2 . After VDCS, there was a significant increase in the mean serum 25-hydroxyvitamin D (52.0 vs. 66.4 nmol/L, p < 0.001) and the mean urinary calcium excretion (3.80 vs. 5.64 mmol/d, p < 0.001). Eight (23.5%) patients developed de novo hypercalciuria. After a median followup of 39 (range: 7-60) months, 50% of hypercalciuric patients developed stones compared with 11.5% of non-hypercalciuric patients (p = 0.038). Conclusion: This study showed a significant effect of combined VDCS on mean urinary calcium excretion, de novo hypercalciuria, and stone development in VDI patients with history of urolithiasis. Therefore, VDI urolithiasis patients receiving VDCS are advised to have monitoring with 24-hour urine collections and imaging studies. Although small, our sample size was good enough to validate the statistical outcomes. Prospective studies are needed to confirm these results.

Introduction: We sought to assess the incidence and risk factors for stone development in patients with end-stage renal disease (ESRD) on hemodialysis (HD). Methods: Medical records of patients receiving HD between 2007 and 2017 were retrospectively reviewed. Patients who had been on HD for at least three months and had imaging studies (computed tomography [CT] scans or ultrasound [US]) pre- and post-initiation of HD were included. Exclusion criterion was presence of stones pre-HD. De novo stones were defined as renal stones found on followup imaging. Demographics, laboratory data, comorbidities, and dialysis characteristics were compared between non-stone-formers and stone-formers using propensity score matching. Results: A total of 133 patients met the inclusion criteria. Their median age was 68.5 years, median body mass index 28.7 kg/m2, and median dialysis duration 59.5 months. After HD, 14 (10.5%) patients developed de novo stones and their median dialysis-to-stone duration was 23.5 months. When compared with non-stone-formers, stone-formers had significantly lower incidence of hypertension (48.2% vs. 14.3%; p=0.03), lower serum ionized calcium (1.16 vs. 1.07 mmol/L; p=0.01) and magnesium (0.95 vs. 0.81 mmol/L; p=0.01), and significantly higher serum uric acid (281.5 vs. 319.0 mmol/L; p=0.03). Multivariate analysis demonstrated that lower serum ionized calcium (adjusted odds ratio [OR] 0.00001; 95% confidence interval [CI] 0–0.18) and magnesium (adjusted OR 0.0003; 95% CI 0–0.59) were significantly associated with stone formation. Conclusions: The incidence of de novo nephrolithiasis in ESRD patients on HD was 10.5%. Increased serum uric acid, decreased serum magnesium and ionized calcium, and absence of hypertension were associated with increased stone-formation in ESRD patients on HD.

Objective: To evaluate the role of incomplete metastasectomy (IM) for patients with metastatic renal cell carcinoma (mRCC) on overall survival (OS) and time to introduction of first-line systemic therapy. Methodology: Patients diagnosed with mRCC between Jan 2011 and Apr 2019 in 16 centers were selected from the Canadian Kidney Cancer information system database. We included mRCC patients who had prior nephrectomy and had received an IM (resection of at least 1 metastasis) or no metastasectomy (NM). A propensity score matching was performed to minimize selection bias. Cox proportional hazards analysis was used to assess the impact of the metastasectomy while adjusting for potential confounders. OS was assessed by Kaplan-Meier analysis. Results: A total of 138 patients with mRCC underwent IM, while 1221 patients did not. On multivariate analysis, IM did not improve OS (hazard ratio [HR] 0.96, 95% CI 0.63 to 1.45, P = 0.836) However, subgroup analyses revealed IM improved OS compared with NM when lungs were the only site involved (median time to OS not reached versus 66 months, respectively; P = 0.014). Additionally, lung metastasectomy delayed the systemic therapy compared with NM (median 41 and 13 months, respectively, P = 0.014). IM of endocrine organs (thyroid, pancreas, adrenals) or bone metastases did not impact OS. Conclusion: The role of IM for mRCC is limited. Incomplete resection of lung metastases was associated with improved OS and delayed time to introduction of systemic therapy when lungs were the sole location of metastatic disease. Despite case-matching, unknown unadjusted confounders may explain the relationship between IM and survival in this analysis.

Pneumoscrotum is a rare physical exam finding that is commonly associated with life-threatening perineal infections or secondary causes from visceral or pulmonary injury.1 However, it is usually found in conjunction with multiple other concerning physical exam findings. In this report, we describe a young competitive diver who presented with isolated pneumoscrotum, which eventually was found to be due to a spontaneous tracheal tear