Expression and function of intestinal hexose transporters after small intestinal denervation.

BACKGROUND: The role of neural regulation in expression and function of intestinal hexose transporters is unknown. The aim of this study is to determine the role of intestinal innervation in gene expression and function of the membrane hexose transporters, SGLT1, GLUT2, and GLUT5 in the enterocyte. We hypothesize that denervation of the small intestine decreases expression of hexose transporters, which leads to decreased glucose absorption. METHODS: Six groups of Lewis rats were studied (n = 6 each) as follows: control, 1 week after sham laparotomy, 1 and 8 weeks after syngeneic (no immune rejection) orthotopic small-bowel transplantation (SBT) (SBT1 and SBT8) to induce complete extrinsic denervation, and 1 and 8 weeks after selective disruption of intrinsic neural continuity to jejunoileum by gut transection and reanastomosis (T/A1 and T/A8). All tissue was harvested between 8 AM and 10 AM. In duodenum, jejunum, and ileum, mucosal messenger RNA (mRNA) levels were quantitated by real-time polymerase chain reaction (PCR), protein by Western blotting, and transporter-mediated glucose absorption using the everted sleeve technique. RESULTS: Across the 6 groups, the relative gene expression of hexose transporter mRNA and protein levels were unchanged, and no difference in transporter-mediated glucose uptake was evident in any region. The glucose transporter affinity (K(m)) and functional transporter levels (V(max)) calculated for duodenum and jejunum showed no difference among the 6 groups. CONCLUSION: Baseline regulation of hexose transporter function is not mediated tonically by intrinsic or extrinsic neural continuity to the jejunoileum.

Hexose transporter expression and function in mouse small intestine: role of diurnal rhythm.

BACKGROUND: Expression and function of hexose transporters vary diurnally in rat small intestine; however, this subject remains unexplored in mice. AIM: The aim of the study was to investigate the diurnal expression and function of hexose transporters SGLT1, GLUT2, and GLUT5 in mouse small bowel. METHODS: Twenty-four c57bl6 mice maintained in a 12-h light/dark room (6 AM: -6 PM: ) were sacrificed at 9 AM: , 3 PM: , 9 PM: , and 3 AM: (n = 6 each). In duodenal, jejunal, and ileal mucosa, total cellular mRNA and protein levels were quantitated by real-time PCR and semiquantitative Western blotting, respectively. The everted sleeve technique measured transporter-mediated glucose uptake at 9 AM: and 9 PM: . RESULTS: mRNA expression of SGLT1, GLUT2, and GLUT5 varied diurnally in all three intestinal segments (p 70% of food intake occurred; glucose transport followed a similar pattern with increased uptake at 9 PM: . CONCLUSION: Hexose transporter expression and function vary diurnally with nocturnal feeding patterns of mice.

Combined transabdominal gastroplasty and fundoplication for shortened esophagus: impact on reflux-related and overall quality of life.

BACKGROUND: Transabdominal gastroplasty for shortened esophagus at the time of fundoplication results in a segment of aperistaltic, acid-secreting neoesophagus above the fundoplication. We hypothesized that transabdominal gastroplasty impairs quality of life (QOL). METHODS: This was a matched paired analysis with retrospective chart review and follow-up questionnaire of 116 patients undergoing transabdominal fundoplication with gastroplasty with 116 matched controls undergoing transabdominal fundoplication alone from January 1997 to June 2005. Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36) and Quality Of Life in Reflux And Dyspepsia (QOLRAD) instruments were used to measure overall and reflux-related QOL. Overall response rate was 75%; including 65 matched pairs used for long-term follow-up and QOL analysis. RESULTS: Groups were similar in age, sex, duration of hospitalization, and complications (p > 0.05). Gastroplasty patients had larger hiatal hernias and were more likely to have undergone a previous fundoplication (p < 0.01). No perioperative deaths or major morbidity occurred in 18% of both groups. Survey respondents were older than nonrespondents (p < 0.01). Complications did not impact response rates (p = 0.11). Median follow-up was 14 months in the gastroplasty group and 17 months in controls (p = 0.02). The groups had similar scores on the SF-36 and QOLRAD (p > 0.05) and similar overall frequency of patient satisfaction, perceived health status, and self-reported symptoms of reflux, dysphagia, bloating, diarrhea, and excessive flatus (p > 0.05). Control patients were more likely to require rehospitalization or reinterventions (p = 0.04). CONCLUSIONS: Transabdominal gastroplasty and fundoplication for shortened esophagus is safe and results in similar overall and reflux-related QOL compared with fundoplication alone.

Effect of Roux-en-Y gastric bypass in obese patients with Barrett's esophagus: attempts to eliminate duodenogastric reflux.

BACKGROUND: To assess the effect of Roux-en-Y gastric bypass (RYGB) at a tertiary referral Center of Excellence for bariatric surgery on the length and presence of dysplasia in morbidly obese patients with Barrett's esophagus (BE). Esophageal reflux of gastroduodenal contents (acid, bile) contributes to the development of BE and progression in the dysplasia-carcinoma sequence. Obese patients have a high prevalence of gastroesophageal reflux and might be at an increased risk of developing BE and esophageal adenocarcinoma. The effect of eliminating duodenogastroesophageal reflux on BE is not known. METHODS: We performed a retrospective review of all patients with pre-existing, biopsy-proven, long-segment (>3 cm) BE undergoing RYGB at our institution. Only patients with >1 year of endoscopic, biopsy-controlled follow-up (mean 34 mo) were included. RESULTS: Five patients (3 men and 2 women) were identified. The mean +/- standard error of the mean preoperative length of BE was 6 +/- 2 cm; 2 patients had low-grade dysplasia and 1 indeterminate dysplasia. At the postoperative follow-up (>1 yr) examinations, the length of BE had decreased in 4 patients; the overall length was 2 +/- 1 cm; and only 1 patient had dysplasia. All patients experienced a decrease in the length of BE (n = 4), complete disappearance of BE (n = 2), or improvement in the degree of dysplasia (n = 3). The body mass index had decreased from 43 +/- 4 kg/m(2) to 33 +/- 3 kg/m(2), and all experienced subjective improvement in reflux symptoms postoperatively. RYGB resulted in complete or partial regression of BE in 4 of 5 patients and improvement in reflux symptoms in all. CONCLUSION: Our results suggest that RYGB might be the procedure of choice in morbidly obese patients with BE requiring surgical treatment for gastroesophageal reflux disease.

Coordinated, diurnal hexose transporter expression in rat small bowel: implications for small bowel resection.

BACKGROUND: Hexose transporter mRNA and protein levels follow a diurnal rhythm in rat jejunum. Their coordinated expression and resultant function throughout the small bowel is not well understood. We hypothesized that hexose transporter levels and glucose absorption follow a coordinated, site-specific diurnal rhythm in rat duodenum and jejunum, but not in ileum. METHODS: Sprague-Dawley rats were housed in a strictly maintained, 12-h, light/dark room [light 6 am to 6 pm] with free access to water and chow. Mucosa was harvested from duodenum, jejunum, and ileum at 3 am, 9 am, 3 pm, and 9 pm, and full thickness 1-cm segments were harvested at 9 am, and 9 pm (n = 6 for each segment at each time point). mRNA levels were determined by reverse-transcription, real-time polymerase chain reaction (n > or = 5), protein levels by semiquantitative Western blotting (n > or = 5), and transporter-mediated glucose uptake by everted sleeve technique (n = 6). RESULTS: mRNA levels of SGLT1 and GLUT5 followed a temporally coordinated, diurnal rhythm in all 3 segments (P < .01), while mRNA for GLUT2 and protein levels for SGLT1 and GLUT2 varied diurnally only in duodenum and jejunum (P > .05) but not in ileum (P > .10). SGLT1 and GLUT5 mRNA induction decreased aborally. Baseline SGLT1 and GLUT5 mRNA levels and SLGT1 and GLUT2 protein levels did not vary aborally (P > .05 for all). GLUT2 mRNA baseline levels were decreased in ileum (P < .01). Glucose uptake varied diurnally in duodenum and jejunum with no difference in ileum. Transporter-mediated glucose uptake was greater in duodenum and jejunum compared with ileum. CONCLUSION: Regulation of hexose absorption in rat small bowel seems to be site-specific and mediated by multiple mechanisms.

Development of a simple model of extrinsic denervation of the small bowel in mouse.

Small bowel transplantation (SBT) is associated with poorly understood enteric dysfunction. The study of SBT in mice is hindered by the technical difficulty of orthotopic SBT in the mouse. Our aim was to develop an easy preparation of extrinsic denervation of the entire jejunoileum in mice as a model of orthotopic SBT. All neurolymphatic tissues accompanying the superior mesenteric artery (SMA) and vein (SMV) were ligated just distal to the middle colic vessels. The SMA and SMV were then stripped of investing adventitia, and the mesentery to jejunum and colon were transected radially. Jejunum and colon were not transected and reanastomosed. To confirm extrinsic denervation 1, 3, and 6 months later, segments of small bowel were stained for protein gene product 9.5 (PGP9.5) and tyrosine hydroxylase (TH). Tyrosine hydroxylase immunoreactive intensity was then quantified using a semiquantitative analysis. Immunohistochemical fluorescence showed persistence of PGP9.5 immunoreactivity confirming enteric nerves in jejunoileum; however, there was no TH immunoreactivity in jejunoileum in denervated mice despite the expected preservation of TH immunoreactivity in the still-innervated duodenum at 1 month. At 3 months, sparse immunoreactivity for TH was present, and by 6 months, reinnervation of TH-containing nerves appeared similar to controls. Quantification of intensity at each time-point further confirmed this trend. This technique in the mouse accomplishes a complete extrinsic denervation of jejunoileum early postoperatively (1 and 3 months); reinnervation occurs by 6 months. This is an easily learned murine model of orthotopic SBT.

Pancreaticobiliary and duodenal perforations after periampullary endoscopic procedures: diagnosis and management.

OBJECTIVE: To review our experience with management of pancreaticobiliary and duodenal (PB/D) perforations after periampullary endoscopic interventions. Although pancreaticobiliary and duodenal perforations after periampullary endoscopic procedures are rare, their management has not been well described. PATIENTS: Individuals who experienced pancreaticobiliary and duodenal perforations. MAIN OUTCOME MEASURES: Comorbidities, interventions performed, mechanism/site of perforation, management, and hospital morbidity/mortality. RESULTS: Seventy-five perforations (0.6%) occurred in 12,427 procedures; 20 perforations (27%) occurred during biliary stricture dilatation, 18 (24%) during diagnostic endoscopic retrograde cholangiopancreatography, and 15 (20%) during management of choledocholithiasis. Perforations were caused by guidewire insertion in 24 patients (32%), sphincterotomy in 11 (15%), passage of the endoscope in 8 (11%), or stent migration in 7 (9%) and were identified during the index procedure in 45 patients (60%). Delayed presentations included pain in 33 patients (44%), leukocytosis in 26 (35%), and/or fever in 13 (17%) and were diagnosed using computed tomography in 19 patients (25%) and abdominal radiography in 10 (13%); 9 cases (12%) were diagnosed more than 24 hours after the procedure. Indications for operative treatment were gaping duodenal perforations and perforations in patients with surgically altered anatomy. Indications for nonoperative management included contained bile duct perforations and focal duodenal perforations. Management was nonoperative in 53 patients (71%) and operative in 22 (29%). Patients with duodenal perforations, higher American Society of Anesthesia status (P<.01 each), and older age (mean +/- SEM, 65 +/- 4 vs 55 +/- 2 years; P = .02) were more likely to require operative management. Hospital stay (mean +/- SEM, 16 +/- 4 vs 4 +/- 1 days; P<.05) and mortality (13% vs 4%; P<.05) were greater in operative patients (P<.05 each). CONCLUSIONS: Most (70%) pancreaticobiliary and duodenal perforations secondary to periampullary endoscopic interventions can be managed nonoperatively. Most biliary perforations can be managed nonoperatively; a requirement for operative treatment increases the mortality rate.

The influence of transabdominal gastroplasty: early outcomes of hiatal hernia repair.

OBJECTIVE: The aim of our study was to review our experience with transabdominal gastroplasty to determine the safety and short-term efficacy of the procedure. METHODS: Retrospective review of all patients that underwent transabdominal hiatal hernia repair with concurrent gastroplasty for shortened esophagus between October 1999 and May 2004. RESULTS: There were 63 patients, 27 men and 36 women. Median age was 68 years. The hiatal hernia was classified as type-I in 6 patients, type-II in 10, type-III in 43, and type-IV in 4. The operative approach was laparoscopic in 44 patients and laparotomy in 19. A Nissen fundoplication was performed in 62 patients and a Toupet fundoplication in 1. Wedge gastroplasty was performed in 47 patients and modified Collis gastroplasty in 16. Median hospitalization was 3 days (range, 2-10). Intraoperative complications occurred in 11 patients (17%). One laparoscopic approach (2%) was converted to laparotomy. Postoperative complications occurred in 12 patients (19%), there were no operative deaths. Median follow-up was 12 months (range, 0 to 64). One patient (2%) was found to have a recurrent hiatal hernia diagnosed 14 months, postoperatively. Functional results were excellent in 41 (68%), good in 6 (10%), fair in 12 (20%), and poor in 1 (2%). CONCLUSION: Transabdominal gastroplasty can be performed safely, with good functional results and a low incidence of recurrent herniation during the short-term follow-up period.

A two-decade spectrum of revisional bariatric surgery at a tertiary referral center.

BACKGROUND: Ineffective weight loss or complications of previous bariatric surgery often require revisional bariatric procedures. Our aim was to define the indications, operative approach, and outcomes of revisional bariatric procedures during 2 decades at a tertiary center. METHODS: From our prospective database (n = 1584), including 1985-2004, 218 patients (14%) underwent revisional bariatric procedures. Follow-up (mean 7 yr, range 1 mo to 19 yr) data obtained from patient records and questionnaires were current for 98%. Patients were grouped according to operative indications: group 1, unsatisfactory weight loss (n = 97); group 2, mechanical/symptomatic complications (n = 95); and group 3, severe nutritional/metabolic problems (n = 26). RESULTS: The operative mortality rate was 0.9% (1 case each of pulmonary embolus and cardiac arrest). The serious operative morbidity rate was 26% (wound infection in 13%, leak in 3%, pulmonary embolus in 2%, anemia/hemorrhage in 2%, pneumonia/prolonged ventilation in 2%, and other in 4%). Of the 218 patients, 94% underwent conversion to, or revision of, Roux-en-y gastric bypass. Group 1 achieved substantial weight reduction with a mean body mass index from 51 +/- 1 to 38 +/- 1 kg/m(2), the complications resolved in 88% of group 2, and the nutritional/metabolic problems resolved in 79% of group 3. Patients who underwent revisional surgery 1990 were more likely to present with mechanical/symptomatic/metabolic complications than for unsuccessful weight loss (P <.001). CONCLUSIONS: Revisional bariatric surgery is safe and effective in experienced centers. Complications (mechanical/symptomatic/nutritional) or unsatisfactory weight loss after primary bariatric procedures can be treated effectively with revision to Roux-en-y gastric bypass.

The malabsorptive very, very long limb Roux-en-Y gastric bypass for super obesity: results in 257 patients.

BACKGROUND: For the past 11 years, we have used a malabsorptive form of Roux-en-Y gastric bypass (RYGB), the "very, very long limb" RYGB, for selected patients with BMIs >50 kg/m(2) and in highly selected patients with BMI <50 kg/m(2). This modified distal gastric bypass establishes a 100-cm common channel (for digestion and absorption) and a "very, very" long Roux limb of 400 to 500 cm. METHODS: To determine long-term efficacy and complications, we followed prospectively 257 consecutive patients; 188 (73%) participated in a postoperative survey. RESULTS: Of the patients, 60% were female; overall age (x +/- SD) was 45 +/- 11 years, and BMI was 61 +/- 11 kg/m(2). Operative mortality was 1% with substantive postoperative morbidity occurring in 13%. Eighty-two percent of patients returning the survey an average of 48 months postoperatively (range, 12 to 148 months) lost >50% of excess body weight; BMI at follow-up was 37 +/- 9 kg/m(2). Resolution of comorbidities included diabetes mellitus (94%), hypertension (65%), sleep apnea (48%), and asthma (30%). Side effects included mild food intolerance (82%), occasional loose or watery stools (71%), nephrolithiasis (16%), and symptomatic steatorrhea (5%). Nine patients (4%) who developed or were developing impending protein/calorie malnutrition required proximal relocation of the enteroenterostomy with symptom resolution. CONCLUSIONS: Overall, 90% were satisfied with the operation, and 93% would recommend it to a friend. The very, very long limb RYGB is relatively safe and effective and has acceptable side effects in the treatment of selected patients with super obesity (BMI >50). Because of the possibility of malabsorptive sequelae, patients should be selected based on degree of medical sophistication, insight, and compliance.

The diurnal periodicity of hexose transporter mRNA and protein levels in the rat jejunum: role of vagal innervation.

BACKGROUND: Protein and messenger RNA (mRNA) levels of the hexose transporters sodium-dependent glucose transporter-1, glucose transporter 2, and glucose transporter 5 follow a (daily) diurnal rhythm in rat jejunum. Because vagal innervation mediates the diurnal activity of other proteins in the rat small bowel, we hypothesized that the diurnal variation of mRNA and protein levels of these hexose transport proteins are mediated by vagal innervation. METHODS: Forty-eight rats kept in a strictly maintained, alternating 12-hour light-dark room underwent either sham laparotomy (n = 24) or bilateral total abdominal vagotomy (n = 24). Four weeks postoperatively, jejunal mucosa was harvested from 6 rats in each group at 3 am, 9 am, 3 pm and 9 pm; mRNA levels were determined by reverse transcription real-time polymerase chain reaction and protein levels by semiquantitative Western blot analysis. Transporter mRNA and protein levels were expressed as a ratio to the corresponding mRNA and protein levels of the stably expressed housekeeping gene glyceraldehyde-6-phosphate dehydrogenase. RESULTS: mRNA and protein levels for all 3 hexose transporters showed diurnal variation in sham controls (P < or = .01 for all). After vagotomy, although mRNA levels of all 3 transporters showed diurnal variation (each P < .01), diurnal variation in all 3 hexose transporter protein levels was abolished (P > .10 for all). CONCLUSIONS: Vagal innervation appears to differentially mediate the diurnal changes in hexose transporter mRNA and protein expression in the rat jejunum by posttranscriptional, and/or posttranslational processes.

Postprandial augmentation of absorption of water and electrolytes in jejunum is neurally modulated: implications for segmental small bowel transplantation.

Postprandial augmentation of absorption of water and electrolytes is believed to occur in the jejunum. Neural mechanisms of control, however, have not been studied in the in situ jejunum or in the transplanted bowel. The aim of this study was to determine if postprandial augmentation of absorption occurs in the in situ jejunum and to evaluate neural mechanisms controlling postprandial jejunal absorption. Based on our previous work, we hypothesized that postprandial augmentation of absorption does not occur in the jejunum in situ and that extrinsic denervation of the jejunum is associated with decreased postprandial absorption. Absorption was studied in an 80 cm, in situ jejunal segment in six dogs by using an isosmolar electrolyte solution alone, or with 80 mmol/L glucose before and after jejunal transection to disrupt intrinsic neural continuity of the study segment with the remaining gut. Net absorptive fluxes of water and electrolytes were measured in the fasted state and after a 400-kcal meal. Another six dogs were studied 3 weeks after our validated model of extrinsic denervation of jejunoileum; identical fasting and postprandial absorptive states were evaluated. Postprandial augmentation of absorption of water and electrolytes did occur in the jejunum (P < 0.03) both in the absence and in the presence of intraluminal glucose. After intrinsic neural transection or extrinsic denervation, no postprandial augmentation of absorption occurred, with or without glucose. Postprandial augmentation of absorption of water and electrolytes occurs in the in situ jejunum. Disrupting intrinsic neural continuity or extrinsic denervation (as after intestinal transplantation) abolishes postprandial augmentation.

Bilateral staged versus bilateral simultaneous thoracotomy in the pediatric population.

AIM: The aim of the study was to evaluate the safety and outcomes of simultaneous bilateral thoracotomy in pediatric patients compared with traditional bilateral staged thoracotomy. METHODS: This is a retrospective review of 30 consecutive patients 18 years or younger undergoing either bilateral staged or bilateral simultaneous thoracotomy between March 1994 and July 2004. Follow-up (mean, 47 months) was available for all patients. RESULTS: Thirty patients (17 boys, 13 girls; average age, 12 years) underwent bilateral staged or bilateral simultaneous thoracotomy. Eighteen patients underwent staged thoracotomy, 9 patients underwent simultaneous thoracotomy, and 3 patients underwent both procedures. Diagnosis included sarcoma (n = 21), Wilms tumor (n = 4), indeterminate pulmonary nodules (n = 3), and germ cell tumor (n = 2). When we compared outcomes for patients undergoing simultaneous versus staged bilateral thoracotomy, mean hospital stay (5.2 vs 10.6 days; P < .002), intensive care unit stay (1 vs 2 nights; P < .0001), days with tube thoracostomy (4 vs 8 days; P < .0005), and time to initiation of adjuvant chemotherapy (13 vs 30 days; P < .05) were all significantly less for patients undergoing bilateral simultaneous thoracotomy. In addition, postoperative complications were less frequent in patients undergoing simultaneous versus staged thoracotomy (0 vs 3 events; P = .25). CONCLUSIONS: In selected patients, bilateral simultaneous thoracotomy is safe and may lessen morbidity and hospital stay while avoiding delay in initiation of adjuvant chemotherapy.

In vivo complete neural isolation of the rat jejunoileum: a simple model to study denervation sequelae of intestinal transplantation.

BACKGROUND: Our aim was to develop and validate a technically easy, reliable, and reproducible method of complete jejunoileal denervation in the rat to allow study of the physiologic effects of intestinal transplantation devoid of immunologic phenomena and ischemia/reperfusion injury. MATERIALS AND METHODS: Six adult Sprague-Dawley rats underwent transection and reanastomosis of the proximal jejunum and proximal colon, transection of all neurolymphatic tissues at the base of the mesentery, stripping adventitia off the superior mesenteric artery and vein, and radial transection of the intervening mesenteries, thereby denervating the jejunoileum in situ without disrupting blood flow. Three rats each were sacrificed 1 and 6 months later. Intestinal smooth muscle from the still-innervated duodenum and the denervated jejunum, mid-small bowel, and ileum was compared to corresponding tissues from a normal rat for tyrosine hydroxylase immunohistochemistry, a marker of extrinsic innervation. RESULTS: One and six months after denervation, all duodenal samples demonstrated normal tyrosine hydroxylase immunostaining. In contrast, tyrosine hydroxylase immunoreactivity was undetectable in jejunum, mid-small bowel, or ileum of rats at 1 month and 2 of the 3 rats at 6 months; 1 rat at 6 months had low levels of tyrosine hydroxylase immunoreactivity at the mesenteric border of jejunum and mid small bowel. CONCLUSION: This simple technique of in situ neural isolation effectively and reproducibly achieves complete extrinsic denervation of the entire rat jejunoileum. Low levels of neural regeneration may be present 6 months after denervation.

Lung abscess due to retained gallstones with an adenocarcinoma.

We describe a patient who had a right lower lobe mass containing calcifications consistent with gallstones develop 3(1)/(2) years after laparoscopic cholecystectomy. Thoracotomy revealed a chronic abscess containing pigmented gallstones and an adjacent area of bronchoalveolar adenocarcinoma involving both N1 and N2 lymph nodes.

Is Roux-en-Y gastric bypass safe after previous antireflux surgery? Technical feasibility and postoperative symptom assessment.

BACKGROUND: Clinically significant morbid obesity is associated with an increased risk of gastroesophageal reflux disease. Vertical Roux-en-Y gastric bypass (RYGBP) is known to eliminate acid (and bile) in the pouch of cardia, which would provide control of reflux symptoms. The aim of our study was to assess the technical considerations, morbidity, and safety of RYGBP after previous antireflux surgery and evaluate postoperative reflux symptoms. METHODS: Retrospective review of all patients undergoing RYGBP after previous antireflux surgery from three institutions. Follow-up (mean 18 months) data were obtained from medical records and by questionnaire. RESULTS: A total of 19 patients (18 women and 1 man) underwent standard (n = 18) or distal (n = 1) RYGBP 8 +/- 1 years after Nissen (n = 18) or Toupet (n = 1) fundoplication. Open RYGBP was undertaken in 17 of 19 patients. No postoperative deaths occurred. Substantive complications occurred in 4 patients (21%) and included hemorrhage requiring transfusion, concomitant splenectomy, and reoperation for suspected leak in 2. Of the 19 patients, 16 returned the questionnaire, 15 of whom reported subjective improvement in reflux symptoms after RYGBP compared with after antireflux surgery. No patient in this series required medical therapy for reflux symptoms at the last follow-up visit. The body mass index decreased from 42 +/- 2 kg/m(2) to 32 +/- 2 kg/m(2) (mean +/- SEM); all patients with >or=1 year of follow-up had a body mass index of

Enteric hyperoxaluria, nephrolithiasis, and oxalate nephropathy: potentially serious and unappreciated complications of Roux-en-Y gastric bypass.

BACKGROUND: Neither the presence nor prevalence of enteric hyperoxaluria has been recognized after Roux-en-Y gastric bypass (RYGBP). We have noted a high rate of oxalate nephrolithiasis and even 2 patients with oxalate nephropathy in this patient population postoperatively. Our aim was to determine the frequency of the occurrence and effects of enteric hyperoxaluria after RYGBP. METHODS: Retrospective review of all patients at our institution diagnosed with calcium oxalate nephrolithiasis or oxalate nephropathy after standard (n = 14) or distal (n = 9) RYGBP. The mean postoperative follow-up was 55 months. RESULTS: A total of 23 patients (14 men and 9 women; mean age 45 years; mean preoperative body mass index 55 kg/m(2)) developed enteric hyperoxaluria after RYGBP, defined by the presence of oxalate nephropathy (n = 2) or calcium oxalate nephrolithiasis (n = 21) and increased 24-hour excretion of urinary oxalate and/or calcium oxalate supersaturation. Enteric hyperoxaluria was recognized after a mean weight loss of 46 kg at 29 months (range 2-85) after RYGBP. Two patients developed renal failure and required chronic hemodialysis. Of the 21 patients with nephrolithiasis, 14 had no history of nephrolithiasis preoperatively, and 19 of 21 required lithotripsy or other intervention. Of the 23 patients, 20 tested had increased oxalate excretion, and 14 of 15 tested had high urine calcium oxalate supersaturation. CONCLUSION: Enteric hyperoxaluria, nephrolithiasis, and oxalate nephropathy must be considered with the other risks of RYGBP. Efforts should be made to identify factors that predispose patients to developing hyperoxaluria.

Surgical management of amiodarone-associated thyrotoxicosis: Mayo Clinic experience.

Amiodarone-associated thyrotoxicosis (AAT) is often poorly tolerated owing to underlying cardiac disease, and it is frequently refractory to conventional medical treatment. The goal of this study was to describe the patient characteristics, management, and outcomes of all the patients treated surgically for AAT at a single institution. We conducted a retrospective chart review of all patients managed surgically for AAT (April 1985 through November 2002) at the Mayo Clinic in Rochester, Minnesota. Altogether, 29 men and 5 women, ages 39 to 85 years (median 60 years), treated with amiodarone for 3 to 108 months underwent near-total or total thyroidectomy. Frequent symptoms were worsening heart failure, fatigue, weight loss, and tremor. Altogether, 12 patients failed medical management of their AAT, and 21 received no preoperative medical therapy. One patient had been successfully managed medically but required definitive treatment. Common indications for operation were the need to remain on amiodarone, cardiac decompensation, medically refractory disease, and severe symptoms, both hyperthyroid and cardiac, necessitating prompt resolution. The median+/-SD American Society of Anesthesiologists (ASA) classification (1 = healthy through 5 = moribund) was 3.00+/-0.58. A total of 27 specimens had histology consistent with AAT. Complications included death (n = 3), rehospitalization (n = 3), symptomatic hypocalcemia (n = 2), pneumonia (n = 2), cervical hematoma (n = 1), prolonged ventilatorywean (n = 1), and stroke (n = 1); one patient developed hypotension, adult respiratory distress syndrome, and sepsis. Of the 31 surviving patients, 25 (80%) remained on amiodarone postoperatively. The median follow-up was 29 months, at which time all surviving patients were free of hyperthyroid symptoms. Thyroidectomy is an effective treatment for AAT but has a high incidence of perioperative morbidity and mortality. The cardiovascular co-morbidities and high operative risk in this group of patients may account for the increased complication rate.