The association between sleeve gastrectomy and histopathologic changes consistent with esophagitis in a rodent model

No Long-Term Mucosal Lesions in the Esophagus but More Gastric Mucosal Lesions after Sleeve Gastrectomy in Obese Rats

Sleeve gastrectomy (SG) often induces gastroesophageal reflux, with few and discordant long-term data on the risk of Barrett's esophagus (BE) in operated patients. The aim of this study was to analyze the impact of SG on esogastric mucosa in a rat model at 24 weeks postoperatively, which corresponds to approximately 18 years in humans. After 3 months of a high-fat diet, obese male Wistar rats were subjected to SG (n = 7) or sham surgery (n = 9). Esophageal and gastric bile acid (BA) concentrations were measured at sacrifice, at 24 weeks postoperatively. Esophageal and gastric tissues were analyzed by routine histology. The esophageal mucosa of the SG rats (n = 6) was not significantly different in comparison to that of the sham rats (n = 8), with no esophagitis or BE. However, there was more antral and fundic foveolar hyperplasia in the mucosa of the residual stomach 24 weeks after SG than in the sham group (p < 0.001). Luminal esogastric BA concentrations did not differ between the two groups. In our study, SG induced gastric foveolar hyperplasia but no esophageal lesions at 24 weeks postoperatively in obese rats. Therefore, long-term endoscopic esophageal follow-up that is recommended in humans after SG to detect BE may also be useful for detecting gastric lesions.

Sleeve Gastrectomy with Pyloroplasty in Wistar Rats: Assessment of Gastric Emptying, Intestinal Transit, and Possible Duodenogastric Alkaline Reflux

BACKGROUND

Studies indicate sleeve gastrectomy (SG) as a factor of aggravation or even emergence of symptoms of gastroesophageal reflux disease. Accelerated gastric emptying is described as a mitigating factor. SG may be potentiated by adding a pyloroplasty, although with the potential risk of resulting in duodenogastric alkaline reflux. The objective was to standardize sleeve gastrectomy with pyloroplasty in rats, analyze the complementation in terms of mortality and weight evolution, and conduct assessments on gastric emptying, intestinal transit, and genesis of possible duodenogastric reflux.

METHODS

Ninety-three male Wistar rats were divided into a pilot study (standardization of the surgical technique and the scintigraphic study), and the main study. They were then subdivided into the SHAM group, the sleeve gastrectomy (SG) group, and the sleeve gastrectomy with pyloroplasty (SGP) group. After 3 months, the animals were submitted to two scintigraphic experiments and histological analysis of gastric biopsies.

RESULTS

The surgical groups (SG and SGP) lost initially more weight than the SHAM group, and the gastric emptying and intestinal transit in the first were more accelerated. However, no difference was found between the SG and SGP groups. Scintigraphic and histological analyses did not reveal statistical differences among the SG and SGP groups regarding gastroesophageal and duodenogastric refluxes.

CONCLUSIONS

Pyloroplasty did not affect weight reduction or increase duodenogastric reflux, after three postoperative months in this animal model of sleeve gastrectomy.

The Protective Effect of Transit Bipartition and Its Modification Against Sleeve Gastrectomy-Related Esophagitis in a Rodent Model

BACKGROUND

The protective effect of transit bipartition against esophagitis has not yet been proven. Thus, we investigate and compare the bariatric outcomes and esophagus' histological changes of sleeve gastrectomy (SG), SG with transit bipartition (SG-TB), and the proximal SG-TB (SG-PTB) in a rodent model.

METHODS

This study included 45 diabetic Sprague-Dawley rats assigned to one of the four groups, SG-PTB (n = 15), SG-TB (n = 12), SG (n = 10), and SHAM (n = 8). Eight surviving rats from each group were included for further investigation. Histological analysis of the gastroesophageal junction was performed. Body weight, food intake, glucose control, and hormonal changes (glucagon-like peptide-1 and insulin) were assessed before and after surgery in all groups.

RESULTS

Preoperatively, no significant differences were observed in food intake, body weight, and fasting blood glucose levels among the groups. Postoperatively, the SG-PTB and SG-TB groups showed significantly superior glucose control compared to the SG group following the gavage of glucose (p < 0.05). Postoperatively, the SG-PTB and SG-TB groups had higher postoperative GLP-1 levels than postoperative SG and SHAM groups. More severe esophageal hyperpapillomatosis (EHP) of the esophageal section was observed in the SG group. The mucosal height of the SG group was significantly higher than that of the SG-PTB, SG-TB, and SHAM groups (p < 0.05).

CONCLUSION

The transit bipartition procedure may protect the distal esophagus from histological changes associated with esophagitis. Clinical studies are needed to confirm the anti-reflux effects of transit bipartition.

Morphological alterations in gastrointestinal organs of western-diet obese rats submitted to vertical sleeve gastrectomy or Roux-en-Y gastric bypass

To assess the effect of vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) on the esophageal and intestinal morphology of western diet (WD)-obese rats and to characterize the stomach histopathology of WD rats submitted to VSG. Male Wistar rats received WD from 2-4 months of age, to induce obesity, before randomly submitting them to pseudo (WD-SHAM), VSG (WD-VSG) or RYGB (WD-RYGB) surgeries. Gastrointestinal histomorphometry was performed at 3-months post-surgery. The upper esophagus of VSG and RYGB rats increased luminal area, while reductions in the keratin layer of the mucosa and the tunica muscularis were observed only in the RYGB animals. In the lower esophagus, both surgeries increased keratin layer thickness, but reduced the mucosal mucus content, while RYGB increased the thickness of the tunica mucosa and muscularis. The glandular region of the stomach of WD-VSG rats exhibited hypotrophy, epithelial erosion, fibrosis and moderate inflammatory infiltration. VSG and RYGB increased the villi height in the ileum, and the thickness of the tunica muscularis in the jejunum and ileum of WD rats; furthermore, RYGB augmented the ileal villi height. Thus both approaches induced histomorphological alterations in the esophagus and intestine and VSG damaged the gastric mucosa, even over the long-term.

Impact of bariatric surgery on gastroesophageal reflux disease and esophageal motility

PURPOSE OF REVIEW

Obesity is rapidly increasing in prevalence, and bariatric surgery has become a popular treatment option that can improve all-cause mortality in obese individuals. Gastroesophageal reflux disease (GERD) and esophageal motility disorders are common in the obese population, and the effects of bariatric surgery on these conditions differ depending on the type of bariatric surgery performed.

RECENT FINDINGS

Laparoscopic adjustable gastric banding has declined in popularity due to its contributions to worsening GERD symptoms and the development of esophageal dysmotility. Although laparoscopic sleeve gastrectomy (LSG) is the most popular type of bariatric surgery, a comprehensive assessment for acid reflux should be performed as LSG has been linked with worsening GERD. Novel methods to address GERD due to LSG include magnetic sphincter augmentation and concomitant fundoplication. Due to the decreased incidence of postoperative GERD and dysmotility compared to other types of bariatric surgeries, Roux-en-Y gastric bypass should be considered for obese patients with GERD and esophageal dysmotility.

SUMMARY

Bariatric surgery can affect esophageal motility and contribute to worsening or development of GERD. A thorough workup of gastrointestinal symptoms before bariatric surgery should be performed with consideration for formal testing with high-resolution manometry and pH testing. Based on these results, the choice of bariatric surgery technique should be tailored accordingly to improve clinical outcomes.

Gastroesophageal Reflux After Sleeve Gastrectomy

Sleeve gastrectomy continues to be the most commonly performed bariatric operation worldwide. Development or worsening of pre-existing GERD has been recognized as a significant issue postoperatively. There is a paucity of information concerning the most appropriate preoperative workup and the technical and anatomical factors that may or may not contribute to the occurrence of reflux symptoms. Contemporary data quality is deficient given the predominantly retrospective nature, limited follow-up time, and heterogeneous outcome measures across studies. This has produced mixed results regarding the postoperative incidence and severity of GERD. Ultimately, better-constructed investigations are needed in order to offer evidence-based recommendations that may guide preoperative workup and improved patient selection criteria.

Gastroesophageal reflux disease, obesity and laparoscopic sleeve gastrectomy: The burning questions

Obesity is a global health epidemic with considerable economic burden. Surgical solutions have become increasingly popular following technical advances leading to sustained efficacy and reduced risk. Sleeve gastrectomy accounts for almost half of all bariatric surgeries worldwide but concerns regarding its relationship with gastroesophageal reflux disease (GERD) has been a topic of debate. GERD, including erosive esophagitis, is highly prevalent in the obese population. The role of pre-operative endoscopy in bariatric surgery has been controversial. Two schools of thought exist on the matter, one that believes routine upper endoscopy before bariatric surgery is not warranted in the absence of symptoms and another that believes that symptoms are poor predictors of underlying esophageal pathology. This debate is particularly important considering the evidence for the association of laparoscopic sleeve gastrectomy (LSG) with de novo and/or worsening GERD compared to the less popular Roux-en-Y gastric bypass procedure. In this paper, we try to address 3 burning questions regarding the inter-relationship of obesity, GERD, and LSG: (1) What is the prevalence of GERD and erosive esophagitis in obese patients considered for bariatric surgery? (2) Is it necessary to perform an upper endoscopy in obese patients considered for bariatric surgery? And (3) What are the long-term effects of sleeve gastrectomy on GERD and should LSG be done in patients with pre-existing GERD?