Joseph Ellen

Steatorrhea and Hyperoxaluria Occur after Gastric Bypass Surgery in Obese Rats Regardless of Dietary Fat or Oxalate

PURPOSE We determined the effect of dietary fat and oxalate on fecal fat excretion and urine parameters in a rat model of Roux-en-Y gastric bypass surgery. MATERIALS AND METHODS Diet induced obese Sprague-Dawley® rats underwent sham surgery as controls (16), or Roux-en-Y gastric bypass surgery (19). After recovery, rats had free access to a normal calcium, high fat (40%) diet with or without 1.5% potassium oxalate for 5 weeks and then a normal (10%) fat diet for 2 weeks. Stool and urine were collected after each period. Fecal fat was determined by gas chromatography and urine metabolites were evaluated by assay spectrophotometry. RESULTS Daily fecal fat excretion remained low in controls on either diet. However, Roux-en-Y gastric bypass rats ingested a food quantity similar to that of controls but had eightfold higher fecal fat excretion (p <0.001) and heavier stools (p = 0.02). Compared to controls, gastric bypass rats on the high fat diet with potassium oxalate had a fivefold increase in urine oxalate excretion (p <0.001), while gastric bypass rats without potassium oxalate had a twofold increase in urine calcium (p <0.01). Lowering dietary fat in gastric bypass rats with potassium oxalate led to a 50% decrease in oxalate excretion (p <0.01), a 30% decrease in urine calcium and a 0.3 U increase in urine pH (p <0.001). CONCLUSIONS In this Roux-en-Y gastric bypass model high fat feeding resulted in steatorrhea, hyperoxaluria and low urine pH, which were partially reversible by lowering the dietary fat and oxalate content. Roux-en-Y gastric bypass rats on normal fat and no oxalate diets excreted twice as much oxalate as age matched, sham operated controls. Although Roux-en-Y gastric bypass hyperoxaluria appears primarily mediated by gut and diet, secondary causes of oxalogenesis from liver or other mechanisms deserve further exploration.

Serum levels of enclomiphene and zuclomiphene in men with hypogonadism on long‐term clomiphene citrate treatment

To determine the relative concentrations of enclomiphene (ENC) and zuclomiphene (ZUC) isomers in men with hypogonadism on long‐term clomiphene citrate (CC) therapy, and to determine whether patient age, body mass index (BMI) or duration of therapy were predictive of relative concentrations of ENC and ZUC.

A retrospective review of single-institution outcomes with robotic-assisted microsurgical varicocelectomy

We report the largest single-center experience with robotic-assisted microscopic varicocelectomy (RAMV) in male infertility. From August 2012 to February 2015, men with infertility of at least a year and varicoceles underwent RAMV by a single surgeon. Varicocele was diagnosed on physical examination and confirmed by ultrasound by a single ultrasonographer. Preoperative hormone panel, semen analyses, and testicular Doppler ultrasound were obtained from all men and repeated at 3 months. One hundred and forty consecutive men (258 varicocelectomies) were included. Mean age and duration of infertility was 36.4 and 2.8 years, respectively. Median total and free testosterone increased by 145 ng dl−1 and 4.3 pcg ml−1 (44.3%), respectively (P < 0.0001). Median sperm concentration increased by 37.3% (P < 0.03). Median sperm motility and morphology did not significantly change. Median left and right testicular volume increased by 22.3% (P < 0.0001) and 12.6% (P < 0.0006), respectively. Hydroceles occurred 0.8% of procedures. We had no testicular artery injuries. Persistence of varicocele by Doppler ultrasound was 9.6%. Only 37.3% of patients required pain medications postoperatively. We concluded that RAMV is a safe and effective alternative for varicocele repair with outcomes comparable to historical traditional microsurgical approach.

Evaluating Region of Interest Measurement Strategies to Characterize Upper Urinary Tract Stones on Computerized Tomography

Purpose: Computerized tomography imaging is regularly used to assess stone HU values as a surrogate for stone composition and fragility. Techniques for measuring HU values are unstandardized, leading to high variability. We investigated several region of interest measurement strategies to quantify this variability. Materials and Methods: Patients from an institutional database who underwent preoperative computerized tomography, surgical stone extraction and stone composition analysis were identified. HU measurements were made of each patient stone using transverse/coronal slices in the abdominal/bone windows with 4 region of interest techniques, including 1) the maximum diameter region of interest, 2) the maximum diameter region of interest at all stone inclusive slices, 3) 2 equal‐sized, nonoverlapping circular regions of interest and 4) 3 to 5 smaller nonoverlapping regions of interest randomly placed on the stone. Stones that were 80% or greater pure by composition were separately analyzed. Results: A total of 172 patients were included in study. Mean ± SD stone size was 19.3 ± 15.6 mm. On subtype analysis 51 stones were calcium oxalate monohydrate, 9 were calcium oxalate dihydrate, 7 were calcium phosphate hydroxyapatite/brushite and 16 were uric acid. Mean HU values in the abdominal window for all stones identified by region of interest techniques 1 to 4 were 457 ± 253, 351 ± 210, 581 ± 363 and 587 ± 329, respectively. The distribution of means significantly differed across region of interest techniques, planes and windows when considering all stones together (p <0.0001), stones with greater than 80% calcium oxalate dihydrate (p = 0.0113) and greater than 80% calcium oxalate monohydrate (p <0.0001), and uric acid stones (p <0.0001). Conclusions: HU values obtained to assess stone density vary depending on window, plane and region of interest technique. We recommend that clinicians select a single region of interest measurement technique and use it consistently to minimize interinstitutional variability.