Factors associated with Clostridium difficile infection: A nested case-control study in a three year prospective cohort.

BACKGROUND: Clostridium difficile infection (CDI) is a serious medical condition that is associated with substantial morbidity and mortality. Identification of risk factors associated with CDI and prompt recognition of patients at risk is key to successfully preventing CDI. METHODS: A 3-year prospective, observational, cohort study was conducted in a French university hospital and a nested case-control study was performed to identify risk factors for CDI. Inpatients aged 18 years or older, suffering from diarrhea suspected to be related to CDI, were asked to participate. RESULTS: A total of 945 patients were included, of which 233 cases had a confirmed CDI. CDI infection was more common in men (58.4%) (P = 0.04) compared with patients with diarrhea not related to C. difficile. Previous hospitalization (P < 0.001), prior treatment with antibiotics (P = 0.001) or antiperistaltics (P = 0.002), liver disease (P = 0.003), malnutrition (P < 0.001), and previous CDI (P < 0.001) were significantly more common in patients with CDI. Multivariate logistic regression analysis showed that exposure to antibiotics in the last 60 days (especially third generation cephalosporins and penicillins with ß-lactamase inhibitor), chronic renal or liver disease, malnutrition or previous CDI, were associated with an independent high risk of CDI. Age was not related with CDI. CONCLUSIONS: This study showed that antibiotics and some comorbid conditions were predictors of CDI. Patients at high risk of acquiring CDI at the time of admission may benefit from careful monitoring of antibiotic prescriptions and early attention to infection control issues. In future, these "high-risk" patients may benefit from novel agents being developed to prevent CDI.

Safety and long-term outcome of a new concept for surgical adhesion-reduction strategies (Prevadh): a prospective, multicenter study.

BACKGROUND/AIMS: No agent has been consistently effective in preventing formation of peritoneal adhesions and postoperative bowel obstruction after abdominal surgery. The aim of this prospective multicenter study was to assess clinical safety and efficiency of a new adhesion-reduction barrier METHODOLOGY: Between September 2000 and April 2001, Prevadh was used in 78 patients. Operative procedures included 25 hepatic resections, 7 cholecystectomies, 32 colonic resections, 7 protectomies, 3 colostomy or recovery of continuity, 1 gynaecologic surgery and 3 others. Eleven patients were operated on by laparoscopy and 67 by laparotomy. RESULTS: The overall incidence of abscesses and wound complications was 2.4% and 9% respectively. After a mean follow-up of 36 months (range: 4-51 months), no patients experienced adverse events related to the adhesion barrier. Surgical reoperative procedures were performed in 10 patients for unrelated causes and no bowel obstruction occurred within the protected area. CONCLUSIONS: This study confirmed the safety of Prevadh adhesion barrier and suggested that this resorbable barrier might provide prevention from adhesion formation on peritoneal injured surfaces. However, a large randomized controlled trial remains necessary to prove the real effectiveness of adhesion barriers on clinical long-term outcome.

Cystic involvement of the roof of the main biliary convergence in adult patients with congenital bile duct cysts: a difficult surgical challenge.

BACKGROUND: Complete cyst excision of the extrahepatic disease component with biliary reconstruction on proximal healthy bile ducts is considered to be the treatment of choice in patients with congenital bile duct cysts (BDC). Proximal cystic disease that extends to the roof of the main biliary convergence (MBC) might challenge this standard of surgical care. METHODS: A retrospective multicenter study was conducted in 4 European surgical centers concerning their experience with adult patients suffering from type I and IV BDC according to the Todani classification. Clinical presentation, operative management, and postoperative outcome were compared between patients with or without proximal extrahepatic cystic disease that involved at least the roof of the MBC (defined as being BDC with MBC involvement subgroup). RESULTS: From an overall series of 49 adult patients suffering from type I or IV BDC according to the Todani classification, 7 patients had BDC with MBC involvement (14%). Patient age, clinical presentation, duration of symptoms, associated major coexistent hepatobiliary and pancreatic diseases, and synchronous cancer were not significantly different in these patients compared with a control group of 42 adult patients with BDC without MBC involvement. Incomplete proximal cyst excision rate was 86% in the cases of BDC with MBC involvement. Early and late postoperative results were similar in BDC with MBC involvement and in the control group of adult patients, but the incidence of subsequent cancer was significantly higher in the BDC with MBC involvement group (29% vs 0%; P < .02). CONCLUSION: BDC that involves the roof of the MBC is a real surgical challenge to obtain complete proximal cystic disease excision. As suggested in this small study, primary incomplete excision of this particular form of BDC might expose the patient to the risk of subsequent cancer, a feature that must be confirmed in larger series.

Dilatation of Sleeve Gastrectomy: Myth or Reality?

OBJECTIVES: The success of longitudinal sleeve gastrectomy (LSG) is perceived as being potentially limited by dilatation of the remaining gastric tube during the follow-up. The aim of this prospective study was to determine the incidence and the characteristics of sleeve dilatation during the first post-operative year. MATERIALS AND METHODS: Gastric volumetry using 3D gastric computed tomography with gas expansion was performed in 54 successive subjects who underwent an LSG for morbid obesity at 3 and 12 months following surgery. Total gastric volume, volume of the gastric tube and the antrum, and diameter of the gastric tube were assessed after multiplanar reconstructions. An increase of at least 25 % of the total gastric volume was considered as sleeve dilatation. Percentage of excess BMI loss (%EBMIL) and daily caloric intakes were recorded during the first 18 months. RESULTS: Sixty-one percent of the subjects experienced sleeve dilatation 1 year after surgery. The gastric tube was mainly involved in the sleeve dilatation process (+91 %). Sleeve dilatation occurred especially in subjects with smaller total gastric volume at baseline (189 vs 236 ml, p = 0.02). Daily caloric intake was similar between the groups at each point of the follow-up. No difference concerning %EBMIL was observed between the groups during the 18 months of follow-up. CONCLUSIONS: Sleeve dilatation occurred in more than 50 % of the patients. Dilatation was not necessarily linked to an increase of daily caloric intake and insufficient weight loss during the first 18 months following surgery. Small LSG at baseline is at higher risk of dilatation.

Should we wait for metabolic complications before operating on obese patients? Gastric bypass outcomes in metabolically healthy obese individuals.

BACKGROUND: A subgroup of obese patients without metabolic disorders has been identified and defined as metabolically healthy but morbidly obese (MHMO). OBJECTIVES: To compare Roux-en-Y gastric bypass (RYGB) outcomes between MHMO and metabolically unhealthy morbidly obese (MUMO) patients to assess whether the obesity phenotype could affect the results. SETTING: A university-affiliated tertiary care center. METHODS: One hundred nineteen consecutive patients underwent RYGB; 102 completed the 2-year follow-up and were divided into 2 groups (MHMO and MUMO) according to Wildman criteria, including blood pressure, triglycerides, high-density lipoprotein cholesterol (HDL-C), fasting blood sugar, C-reactive protein (CRP), and homeostasis model assessment of insulin resistance (HOMA-IR). Weight loss and metabolic parameter changes were analyzed. RESULTS: Twenty-one of 102 (20.6%) patients were identified as MHMO; they were mostly women (90.5%) and were significantly younger than MUMO patients (39.4 ± 9.1 yr versus 47.2 ± 10, P = .001); 12.6% were lost to follow-up. MHMO phenotype was significantly associated with a greater percentage of excess body mass index loss (P = .03), independent of gender, age, and redo procedures. All metabolic parameters were significantly improved 2 years after surgery in the MUMO group. HOMA-IR, CRP, and triglycerides were significantly lower 2 years after surgery in the MHMO group, whereas fasting blood sugar and HDL-C were unchanged. At 2 years of follow-up, 92.3% of the population was metabolically healthy. CONCLUSIONS: RYGB is an effective procedure to achieve weight loss and had a strong positive metabolic effect in both MHMO and MUMO phenotypes. RYGB led to an increase of the metabolically healthy status and may prevent or delay the onset of metabolic disorders.

Bariatric Surgery Outcomes in Sarcopenic Obesity.

BACKGROUND: Sarcopenic obesity is the combination of low muscle mass and strength with increased fat mass. This condition is associated with negative health outcomes. We hypothesized that sarcopenia could be a pejorative factor on surgical weight loss. OBJECTIVE: The objectives of the study are to determine the influence of sarcopenic obesity on gastric bypass and sleeve gastrectomy results regarding weight loss and comorbidities resolution at 3, 6, and 12 months. SETTING: The study was conducted at the University Hospital. METHODS: Sixty-nine obese patients who benefited from bariatric surgery were included. Skeletal muscle mass was determined by the Janssen's equation. Physical performance and muscle strength were determined using the 6-min walk test and the wall sit test. Obese subjects from the lowest tertile of the Skeletal Muscle mass Index (SMI) of Baumgartner were set as sarcopenic. RESULTS: Weight loss outcomes and rate of weight loss failure were not influenced by sarcopenia. At 1 year, mean EBMIL% was 75.4 % ± 5 in sarcopenic subjects vs 67.8 % ±4 in the non-sarcopenic subjects (p = 0.242). Improvement rates of co-morbidities were similar between groups. Skeletal muscle mass was no more different between groups at 1 year after surgery. There was no patient lost to follow-up. CONCLUSIONS: Bariatric surgery remains effective in achieving weight loss target in sarcopenic patients, with similar remission rates of main comorbidities and similar safety profile than in the non-sarcopenic group. Whether bariatric surgery could result in improvement or deterioration of daily living activities disabilities and functional autonomy in sarcopenic obese patients still have to be evaluated.

Impact of Pregnancy on Weight Loss and Quality of Life Following Gastric Banding.

BACKGROUND-OBJECTIVES: Despite pregnancy being a common event following laparoscopic adjustable gastric banding (LAGB), there is little comprehensive data regarding its effect on postoperative outcome. The aim of this study was to assess the impact of pregnancy on the postoperative changes in quality of life (QOL) and total weight loss 3 years after LAGB. SETTING: Multi-institutional, France. METHODS: This is a study of the subgroup of 561 women of childbearing age included in a 3-year prospective multicenter trial assessing the results of patients undergoing LAGB surgery. Data from the 61 women who got pregnant and delivered during the follow-up period were compared with the 270 who did not. RESULTS: Pregnant women achieved lower final weight loss compared to the non-pregnant group [final body mass index (BMI) 35.4 vs. 31.1 kg/m(2), p < 0.0001; excess weight loss (%EBL) 43.6 vs. 64.7 %, p < 0.0001]. Longitudinal assessment demonstrated pregnancy as a significant and independent factor of poor weight loss (p < 0.0001). The timing of conception after LAGB (between the first 18 months or after) had no significant impact on weight loss changes. There was no significant difference in short form-36 health survey (SF-36) QOL scores between both groups. CONCLUSIONS: Pregnancy following gastric banding affects negatively postoperative final weight loss, even if occurring 18 months postoperatively, but has no effect on QOL improvement.

Impact of sleeve gastrectomy volumes on weight loss results: a prospective study.

BACKGROUND: Causes of weight loss failure after sleeve gastrectomy (SG) are still controversial. The impact of the size of the sleeve continues to be debated. OBJECTIVE: The aim of our study was to determine the impact of sleeve volumes assessed at 3 months using gastric computed tomography (CT) on weight loss at 18 months. SETTING: University Hospital, France. METHODS: Sixty-seven obese patients eligible for SG were prospectively evaluated. Sleeve volumes were assessed postsurgery using 3-dimensional gastric CT with gas at 3 months and weight loss outcomes recorded up to 18 months. The population was divided into 2 groups: the first tertile (n = 22) with the smallest gastric volume was defined as the "small sleeve" group (SSG) and the rest of the population (n = 45) was defined as the "without small sleeve" group (WSSG). RESULTS: No patients were lost to follow-up. In the SSG, overall gastric volume was 133±7 mL versus 264±11 mL for the WSSG (P<.0001). Percentage excess body mass index loss (%EBMIL) during the first postoperative 18 months was significantly greater in the SSG compared with the WSSG (P = .04). Although the volume of the gastric tube was not correlated with weight loss (r =-.04, P = .78), there was a negative linear correlation between the volume of the antrum and the %EBMIL at 18 months (r =-.39, P = .005). A narrow gastric tube was also associated with a high digestive intolerance and reflux. CONCLUSION: Our data suggest that performing the sleeve with a not-too-small bougie size and a radical antrectomy could improve weight loss and digestive tolerance.

Medico-legal analysis of legal complaints in bariatric surgery: a 15-year retrospective study.

BACKGROUND: Bariatric surgery for severe obesity has become an effective and accepted treatment for sustained weight loss. OBJECTIVES: The aim of our study was to analyze the complications and issues raised by the experts on which jury or judges' decisions were made for the different types of bariatric surgery. SETTING: University Hospital, France. MATERIALS AND METHODS: We have carried out a retrospective study of 59 expert review dossiers over a period of 15 years (1999-2014) on the different types of bariatric surgery (laparoscopic adjustable gastric band [LAGB], sleeve gastrectomy [SG], Roux-en-Y gastric bypass [RYGB], vertical banded gastroplasty [VBG], and gastric plication [GP]). RESULTS: Of the cases, 81% were women and the average age was 39 years old (range 19 to 68 years). Among the procedures giving rise to the complaints, 40% were for LAGB, 28% for RYGB, and 23% for SG. The most common initial complications were perforations (30%), fistulae (27%), bowel obstruction (14%), vascular injuries (9.5%), and infections (peritonitis, pleurisy, abscesses, and so forth) (8%). Revision surgery was required in 78% of patients, and perioperative complications accounted for 28.5% of dossiers. The experts concluded that fault had occurred in 40% of case. Negligence arising from an error deemed to be an act of negligence was found in 30% of cases, 67% of which were because of delayed diagnosis. Major long-term complications accounted for 8% of dossiers and minor long-term complications for 22%. Forty-seven percent of patients completely recovered. CONCLUSION: Delayed diagnosis was the main error established by the experts. Surgeons should remain vigilant postoperatively after every bariatric surgical procedure.

Laparoscopic pancreatic resection: a preliminary experience of 15 patients.

BACKGROUND/AIMS: Worldwide experience with laparoscopic pancreatic resection remains limited. The aim of the study was to assess the feasibility, safety and outcome of laparoscopic pancreatic resection. METHODOLOGY: 15 consecutive patients suffering from benign cystic pancreatic (n=6), neuroendocrine tumors (n=8) or pancreatic metastasis from renal carcinoma (n=1) undergoing laparoscopic pancreatic resection were retrospectively collected from 5 academic hospitals. RESULTS: Laparoscopic procedure was completed in 10 patients, including 7 distal pancreatectomies (with 5 spleen preservation), 2 tumor enucleations and 1 partial cystic resection. Conversion was due to inappropriate operative finding for laparoscopic approach in 2 patients and for uncontrollable bleeding in 3 patients. Postoperative pancreatic-related complications included pancreatic fistula in 20% and peripancreatic collection in 13% of the patients. CONCLUSIONS: Laparoscopic pancreatic resection is feasible for distal pancreatic tumors. However, successful management of the pancreatic stump remains the challenge of this procedure, in order to achieve a clear benefit in the patient outcome.

Relevance of Roux-en-Y gastric bypass volumetry using 3-dimensional gastric computed tomography with gas to predict weight loss at 1 year.

BACKGROUND: Causes of Roux-en-Y gastric bypass (RYGB) failures are still controversial. Literature data suggest that gastric pouch or gastrojejunal anastomosis distentions over time could be a key factor. Making the hypothesis that progressive distention of RYGB volumes is 1 of the main factors of weight loss failure, the aim of our study was to evaluate bypass volumes changes using repeated 3-dimensional gastric computed tomography with gas and the possible negative correlation with weight loss results at 1 year. METHODS: Thirty-nine patients eligible for RYGB were prospectively included. Gastric bypass volumes were assessed at 3 and 12 months postsurgery performing 3-dimensional gastric computed tomography with gas and weight loss outcomes were recorded during the first postoperative year. RESULTS: There was no loss to follow up. Mean % excess body mass index lost (%EBMIL) at 1 year was 66.7%. Seven patients (17.9%) did not reach Reinhold criteria and were considered as RYGB failures. We found no linear correlation between the 1 year %EBMIL and mean values of the gastric pouch (r=.01; P=.94), and the neo stomach (r=.09 ; P=.57) at 3 months. Revisional surgery was correlated negatively with %EBMIL at 1 year. CONCLUSION: Weight loss at 1 year does not seem to be correlated to RYGB volume changes. Behavioral factors probably play a major role in weight loss failure.

Gastric bypass for obesity in the elderly: is it as appropriate as for young and middle-aged populations?

BACKGROUND: Obesity prevalence increases in elderly population. Bariatric surgery has been underused in patients over 60 because of fears of complications and lower weight loss. We postulated worse outcomes in the elderly in comparison to young and middle-aged population 1 year after gastric bypass. METHODS: We retrospectively analyzed gastric bypass outcomes in young (<40 years), middle-aged (40 to 55 years), and elderly (>60 years) patients between 2007 and 2013. Each subject over 60 (n = 24) was matched with one subject of both the other groups according to gender, preoperative body mass index (BMI), surgical procedure, and history of previous bariatric surgery (n = 72). RESULTS: Older subjects demonstrated higher prevalence of preoperative metabolic comorbidities (70 vs 30 % in the <40-year-old group, p < 0.0001). Mean duration of the surgical procedure, mean length of stay, and early and late complication rates were similar between age groups. A trend towards fewer early complications and less-severe complications in the younger groups was noted. One-year weight loss results were similar between young, middle-aged, and elderly patients (percentage of excess BMI loss (EBL%), 74.4 ± 3.5; 78.9 ± 4.5, and 73.7 ± 4.5 respectively, p = 0.69). Age was not predictive of weight loss failure 1 year after surgery. Remission and improvement rates of comorbidities were similar between age groups 6 months after surgery. CONCLUSIONS: Our study confirms weight loss efficacy of gastric bypass in the elderly with acceptable risks. Further studies evaluating the benefit-risk balance of bariatric surgery in the elderly population will be required so as to confirm the relevance of increasing age limit.

Prospective longitudinal assessment of change in health-related quality of life after adjustable gastric banding.

BACKGROUND: Gastric banding remains a common procedure worldwide. Improving health-related quality of life (HRQOL) has become a major goal in the treatment of patients with chronic diseases, yet there are few comprehensive data regarding the effect of gastric banding on HRQOL. The aim of this study was to evaluate the impact of laparoscopic gastric banding on HRQOL with particular regard to change over time. METHODS: The 262 consecutive patients included between May 2005 and September 2006 in a French multicenter prospective study designed to assess the safety and efficacy of a gastric band were asked to complete the SF36 questionnaire preoperatively and each 6 months during 3 years. The HRQOL scores were compared with community norms, and their longitudinal change was assessed using cross-sectional analysis and mixed-effects linear modeling (individual growth model). RESULTS: One hundred sixty-four patients (63%) provided a preoperative and at least one postoperative SF-36 questionnaire from 12 to 36 months and form the basis of the present study. In all dimensions, the scores of HRQOL were significantly impaired preoperatively and were significantly improved at 3 years. The increase in HRQOL scores was most marked during the first postoperative months; it continued more slowly after 6 months and stabilized after 1 year. The improvement in HRQOL was associated with the decrease in BMI, in all dimensions. CONCLUSION: Gastric banding results in a significant improvement in HRQOL. A return to normal can be expected at 1 year and persists at 3 years. The postoperative improvement in HRQOL is strongly related to weight loss.

Preoperative fat-free mass: a predictive factor of weight loss after gastric bypass.

Weight loss failure occurs in 8% to 40% of patients after gastric bypass (GBP). The aim of our study was to analyse the predictive factors of weight loss at 1 year so as to select the best candidates for this surgery and reduce the failures. We included 73 patients treated by laparoscopic GBP. We retrospectively analysed the predictive factors of weight loss in kilograms as well as excess weight loss in percentage (EWL%) at 1 year. The population was divided into tertiles so as to compare the sub-group with the highest weight loss with the sub-group with the least satisfactory results. The significantly predictive factors of a better weight loss in kilograms were male, higher initial weight (144 versus 118 kg, p = 0.002), a significant early weight loss and a higher preoperative percentage of fat-free mass (FFM%; p = 0.03). A higher FFM% was also associated with a better EWL% (p = 0.004). The preoperative FFM (in kilograms) was the principal factor accounting for the weight loss at 1 year regardless of age, gender, height and initial body mass index (BMI; p < 0.0001). There was a better correlation between FFM and weight loss (Spearman test, p = 0.0001) than between initial BMI and weight loss (p = 0.016). We estimated weight loss at 1 year according to initial FFM using the formula: 0.5 kg of lost weight per kilogram of initial FFM. The initial FFM appears to be a decisive factor in the success of GBP. Thus, the sarcopoenic patients would appear to be less suitable candidates for this surgery.

Prospective, multicenter, 3-year trial of laparoscopic adjustable gastric banding with the MIDBAND™.

BACKGROUND: Although laparoscopic adjustable gastric banding (LAGB) is a popular metabolic/bariatric procedure, few prospective studies have assessed its outcomes. This study aimed to prospectively assess LAGB safety and effectiveness outcomes using the MIDBAND™ (MID, Dardilly, France). METHODS: Between May 2005 and September 2006, 262 morbidly obese patients underwent primary gastric banding with pars flaccida technique in 13 French medical centers. Excess weight loss and change in body mass index (BMI, kilogram per square meter), percentage of patients with comorbidities, and obesity-related complications were recorded. Patients were followed at 6-month intervals for 3 years. A multivariable individual growth model was used to analyze weight change over time and determine potential predictors of weight loss. RESULTS: The majority of patients were female (n = 233, 89%), with mean age of 36.4 ± 9.7 years. At 3 years, LAGB with MIDBAND resulted in significant decrease in mean BMI from 41.8 ± 4.2 to 30.7 ± 5.8 (p < 0.0001). Median excess weight loss and excess BMI loss were 61% and 68%, respectively. The prevalence of obesity-related comorbidities had significantly decreased from 71% to 15% (p < 0.0001). Complications were observed in 26 patients (10%); device-related complications occurred in 20 patients (8.2%), requiring band removal in 8 (3.3%), and port revision in 8 (3.3%). Individual growth analysis identified significant predictors of weight loss including the number of follow-up visits. CONCLUSION: Prospective outcomes demonstrate the safety and efficacy of gastric banding over time using the MIDBAND. Individual growth modeling demonstrated that postoperative weight loss is strongly related to the frequency and consistency of follow-up visits.

High resolution esophageal manometry evaluation in symptomatic patients after gastric banding for morbid obesity.

BACKGROUND: Dysphagia and vomiting are frequent after laparoscopic gastric banding (LAGB). These symptoms could be secondary to esophageal motility disorders. Our aim was to assess esophageal motility and clearance in symptomatic LAGB patients using high resolution manometry (HRM). METHODS: Twenty-two LAGB patients with esophageal symptoms (dysphagia, vomiting, and regurgitations) were included. Esophageal motility was studied using HRM (ManoScan®, Sierra Systems) and classified according to the Chicago classification. RESULTS: The median delay between surgery and manometry evaluation was 6.3 years (range 1-10). Manometric data were considered as normal in only 2 patients. Achalasia was diagnosed in 3 cases, functional EGJ obstruction in 15, hypotensive peristalsis in 2. During swallowing pan-esophageal pressurization was observed in 6 patients, hiatal hernia pressurization in 7 and gastric pouch pressurization in 2. The intra-bolus pressure was elevated in 18 patients. LAGB was deflated in 6 patients and removed in 12. In 2 patients with unchanged symptoms after LAGB removal motility disorders persisted (1 achalasia, 1 functional EGJ obstruction). CONCLUSION: In symptomatic LAGB patients, esophageal dysmotility is frequent. High resolution manometry allows the assessment of esophageal clearance and provides guidance for the choice of treatment.

3D gastric computed tomography as a new imaging in patients with failure or complication after bariatric surgery.

The number of bariatric operations performed each year is increasing. As a result, a rising number of patients in possible need for revisional surgery are referred to bariatric surgeons. But the standard methods of evaluation are often insufficient, and the best strategy remains difficult to choose. In our centre, we have developed 3D gastric computed tomography with air (3D-GCT). The aim of this pilot study was to assess the usefulness of this new image modality as an aid in the decision-making process in patients with failure or complications after bariatric surgery. Twenty patients referred for failure or complications after various bariatric procedures were included in the study. 3D-GCT was performed on a multidetector CT scanner after absorption of effervescent salt diluted in 10 ml of water and IV injection of butylscopolamine. Thin-slice data were transferred to a dedicated 3D workstation creating three-dimensional volume-rendering images of the oesophagus, gastric cavities and anastomoses. The volume of the gastric pouches and the diameter of stoma or anastomoses were measured. No failure or complications were observed. In all patients, 3D-GCT resulted in very impressive precise 3D images of post-surgical anatomy of the stomach. Imaging findings allowed us to identify or to eliminate the common complications of each procedure with a good accuracy, resulting in an aid to choose the best strategy in each patient. In conclusion, our pilot study suggests that 3D-GCT is useful as a decision-making aid in patients with failure or complications after bariatric surgery.

Dynamic analysis of hepatitis C virus replication and quasispecies selection in long-term cultures of adult human hepatocytes infected in vitro.

Primary human hepatocytes were used to develop a culture model for in vitro propagation of hepatitis C virus (HCV). Production of positive- strand full-length viral RNA in cells and culture supernatants was monitored by PCR methods targeting three regions of the viral genome: the 5' NCR, the 3' X-tail and the envelope glycoprotein E2. De novo synthesis of negative-strand RNA was also demonstrated. Evidence for a gradual increase in viral components over a 3 month period was obtained by two quantitative assays: one for evaluation of genomic titre (quantitative PCR) and one for detection of the core antigen. Production of infectious viral particles was indicated by passage of infection to naive hepatocyte cultures. Reproducibility of the experiments was assessed using cultures from three liver donors and eleven sera. Neither the genotype, nor the genomic titre, nor the anti-HCV antibody content, were reliable predictive factors of serum infectivity, while the liver donor appeared to play a role in the establishment of HCV replication. Quasispecies present in hepatocyte cultures established from three different liver donors were analysed by sequencing hypervariable region 1 of the E2 protein. In all three cases, the complexity of viral quasispecies decreased after in vitro infection, but the major sequences recovered were different. These data strongly suggest that human primary hepatocytes are a valuable model for study of persistent and complete HCV replication in vitro and for identification of the factors (viral and/or cellular) associated with successful infection.