Nausea, bloating and abdominal pain in the Roux-en-Y gastric bypass patient: more questions than answers

Prospective Monitoring of Small Intestinal Bacterial Overgrowth After Gastric Bypass: Clinical, Biological, and Gas Chromatographic Aspects

BACKGROUND AND AIMS

Obesity is a predisposing factor for small intestinal bacterial overgrowth (SIBO). The aim of this study was to prospectively evaluate the prevalence of SIBO as well as its clinical, biological, and nutritional aspects before and up to 24 months after a Roux-en-Y gastric bypass (RYGB) surgery.

PATIENTS AND METHODS

Fifty-one patients (mean BMI 46.9 kg/m2, 66.7% women) requesting RYGB were included between 2016 and 2020. Each patient underwent a glucose breath test, a standardized interrogation on functional digestive signs, a dietary survey, a blood test, a fecalogram, and anthropometric data gathering. These investigations were carried out before surgery and at 1, 3, 6, 9, 12, 18, and 24 months after RYGB.

RESULTS

Before surgery, we found a prevalence of 17.6% of SIBO (95% CI = [8.9%; 31.4%]). After RYGB, at the end of 24 months of follow-up, 89.5% of patients developed SIBO. Anal incontinence appeared to be very frequent after surgery, affecting 18.8% of our population 18 months after surgery. We observed positive steatorrhea after surgery with an average of 11.1 g of lipids/24 h despite a significant limitation of dietary lipids (p = 0.0282).

CONCLUSION

Our study corroborates data in the literature on the prevalence of SIBO in severe obesity patients. For the first time, we observed the sudden appearance of SIBO after RYGB, with a correlation between exhaled hydrogen on a breath test and lipid malabsorption on the fecalogram. As a result, these patients develop fatty diarrhea, with frequent fecal incontinence.

The Prevalence of Small Intestinal Bacterial Overgrowth After Roux-en-Y Gastric Bypass (RYGB): a Systematic Review and Meta-analysis

We reviewed the literature on the prevalence of small intestinal bacterial overgrowth (SIBO) after Roux-en-Y gastric bypass (RYGB). Eight studies examining 893 patients were included. The mean age of the patients was 48.11 ± 4.89 years. The mean BMI before surgery and at the time of SIBO diagnosis was 44.57 ± 2.89 kg/m2 and 31.53 ± 2.29 kg/m2, respectively. Moreover, the results showed a 29% and 53% prevalence of SIBO at < 3-year and > 3-year follow-up after RYGB, respectively. Symptoms included abdominal pain, diarrhea, bloating, nausea, vomiting, constipation, soft stool, frequent defecation, flatulence, rumpling, dumping syndrome, and irritable bowel syndrome. SIBO is prevalent after RYGB; digestive symptoms should prompt the consideration of SIBO as a potential etiology. Antibiotic therapy has proven to be therapeutic.

Chronic abdominal pain after bariatric surgery: a narrative review

Objective: This paper reviews the prevalence, etiology, risk factors, diagnosis and prevention of chronic abdominal pain after bariatric surgery. Introduction: Chronic pain is a very common and complex problem that has serious consequences on individuals and society. It frequently presents as a result of a disease or an injury. Obesity and obesity-related comorbidities are a major health problem and are dramatically increasing year after year. Dieting and physical exercise show disappointing results in the treatment of obesity. Therefore, bariatric surgery is increasingly widely offered as a weight reducing strategy. In our pain clinic we see a lot of patients who suffer from chronic abdominal pain after bariatric surgery. This review aims to explore the link between chronic abdominal pain and bariatric surgery in this specific type of patients. Method: The review is based on searches in PubMed, Embase and Cochrane databases. Keywords are used in different combinations. We did a cross-reference of the articles included. Results: Chronic abdominal pain after bariatric surgery is very common. Around 30% of the bariatric patients experience persistent abdominal pain. An explanation for the abdominal pain is found in 2/3 of these patients. There is a wide variety of causes including behavioral and nutritional disorders, functional motility disorders, biliary disorders, marginal ulceration and internal hernia. Another, frequently overlooked, cause is abdominal wall pain. Unexplained abdominal pain after bariatric surgery is present in 1/3 of the patients with persistent abdominal pain. More studies are needed on the risk factors and prevention of unexplained abdominal pain in bariatric patients.

Small Intestinal Bacterial Overgrowth: Clinical Presentation in Patients with Roux-en-Y Gastric Bypass

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is defined by an increased number of bacteria measured via exhaled hydrogen and/or methane gas following the ingestion of glucose. This condition is prevalent following abdominal surgery, including Roux-en-Y gastric bypass (RYGB), and associated with a variety of non-specific abdominal symptoms, often requiring an extensive diagnostic work-up.

AIM

To assess the frequency that individuals with RYGB anatomy are diagnosed with SIBO and if they are more likely to report specific gastrointestinal (GI) symptoms compared to individuals with native anatomy.

METHODS

This large matched cohort study evaluated patients with GI symptoms who underwent a glucose breath test (GBT) for SIBO evaluation, utilizing 1:2 matching between RYGB and native anatomy. Patients with positive GBT were included in univariate and multivariate analyses to distinguish the presence of ten specific GI symptoms between RYGB and native anatomy.

RESULTS

A total of 17,973 patients were included, where 271 patients with RYGB were matched to 573 patients with native anatomy that underwent GBT. Patients with RYGB anatomy and a positive GBT (199; 73.4%) as compared to those with native anatomy and a positive GBT (209; 36%) more often reported nausea, vomiting, bloating, and diarrhea. There were no differences between the two groups in the report of heartburn, regurgitation, chest pain, gas, or constipation.

CONCLUSIONS

SIBO is common in patients with RYGB and more commonly report nausea, vomiting, bloating, and diarrhea. The results of this study suggest that the report of these symptoms in RYGB should prompt early evaluation for SIBO.

Vague abdominal pain after Roux-en-Y gastric bypass: not always an internal herniation: case report and literature review

Background: Roux-en-Y gastric bypass is a frequently carried out bariatric procedure, proven to be effective in the management of obesity and its accompanying health issues. Following its popularity, admission to the emergency department for abdominal pain is often seen with known early and late onset causes. We present a case of a young woman with vague abdominal pain years after her gastric bypass, who eventually underwent a resection of a 'candy cane' like biliopancreatic blind loop.Methods: A healthy 23-year-old woman has been suffering of vague abdominal complaints after a gastric bypass procedure 4 years earlier. Postprandial pain, diarrhoea and abdominal distension were present at a daily to weekly basis. Several investigations and management options were administered by surgeons, gastroenterologists as well as endocrinologists. On a performed explorative laparoscopy, a large blind loop at the entero-enteric anastomosis was seen and resected.Results: At current follow-up of 15 months the resection of the candy cane like blind end of the biliopancreatic loop resulted in a complete withdrawal of our patient's symptoms. A tentative diagnosis of bacterial overgrowth in the blind loop was made.Conclusions: Abdominal pain after gastric bypass is a frequent cause of admission to the emergency department. Besides the more serious complications, internal hernia is often withheld as possible diagnosis in the differential diagnosis of late onset, postprandial epigastric pain. This case report highlights another possibility. At initial surgery, a candy cane shaped blind loop should be avoided both at the gastro-jejunal as well as the entero-enteric anastomosis.

Lactulose Breath Testing Can Be a Positive Predictor Before Weight Gain in Participants with Obesity Submitted to Roux-en-Y Gastric Bypass

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is defined as the colonization of fermentative bacteria in the duodenum and jejunum. The alteration of digestive anatomy promoted by bariatric surgery may be a pre-disposing factor for SIBO. In this context, the prevalence of SIBO in participants undergoing bariatric surgery using Roux-en-Y gastric bypass (BGYR) was evaluated.

METHODS

Participants, both sexes, older than 18 years, were those who (a) had bariatric surgery by the BGYR technique at least 1 year before the data collection and (b) did not use antibiotics recently. The SIBO diagnosis was established through the hydrogen breath test (H₂BT), with intake of lactulose and serial collection of breath samples over 2 h. A test with ≥ 12-point elevation over the basal sample at 60 min after substrate intake was deemed positive.

RESULTS

A total of 18 participants (14 females (77.8%)) were enrolled with a mean age of 50.5 years (range, 23 to 79 years). The interval between surgery and data collection ranged from 5 to 20 years (mean, 11.2 years). The mean preoperative body mass index (BMI) was 44.6 kg/m² (range, 36.7-56.2 kg/m²). The H₂RT with lactulose was positive for SIBO in seven (six female) participants. The participants with negative test measured trough H₂BT with lactulose had a lower mean BMI of 28.69 kg/m², in comparison with the positive group, which presented a mean BMI of 33.04 kg/m² (p value = 0.041).

CONCLUSION

Our data point to a high prevalence of SIBO (38.8%) in patients undergoing BGYR with a value in accordance with the literature. Moreover, the differences in BMI between negative and positive groups by H₂BT with lactulose evidenced a weight gain relapse in participants with SIBO.

Laparoscopic revisional surgery for an unusual complication of Roux-en-Y gastric bypass

With the worldwide epidemic of obesity, there has been an increase in the numbers of primary and revisional procedures of bariatric surgery such as the Roux-en-Y gastric bypass (RYGBP). Nevertheless, this type of surgery is not exempt from complications. An excessive length of non-functional Roux limb proximal to the jejunojejunostomy can cause abnormal upper gastrointestinal symptoms after laparoscopic RYGBP. We present the case of a female patient who presented these unspecific abdominal symptoms after laparoscopic RYGBP who underwent laparoscopic resection in order to reduce the length of the dilated blind loop responsible for the symptoms.

Consequences of Small Intestinal Bacterial Overgrowth in Obese Patients Before and After Bariatric Surgery

BACKGROUND AND AIMS

Small intestinal bacterial overgrowth (SIBO) has been described in obese patients. The aim of this study was to prospectively evaluate the prevalence and consequences of SIBO in obese patients before and after bariatric surgery.

PATIENTS AND METHODS

From October 2001 to July 2009, in obese patients referred for bariatric surgery (BMI >40 kg/m² or >35 in association with comorbidities), a glucose hydrogen (H₂) breath test (BT) was performed before and/or after either Roux-en-Y gastric bypass (RYGBP) or adjustable gastric banding (AGB) to assess the presence of SIBO. Weight loss and serum vitamin concentrations were measured after bariatric surgery while a multivitamin supplement was systematically given.

RESULTS

Three hundred seventy-eight (mean ± SD) patients who performed a BT before and/or after surgery were included: before surgery, BT was positive in 15.4 % (55/357). After surgery, BT was positive in 10 % (2/20) of AGB and 40 % (26/65) of RYGBP (p < 0.001 compared to preoperative situation). After RYGBP, patients with positive BT had similar vitamin levels, a lower caloric intake (983 ± 337 vs. 1271 ± 404 kcal/day, p = 0.014) but a significant lower weight loss (29.7 ± 5.6 vs. 37.7 ± 12.9 kg, p = 0.002) and lower percent of total weight loss (25.6 ± 6.0 vs. 29.2 ± 6.9 %, p = 0.044).

CONCLUSION

In this study, SIBO is present in 15 % of obese patients before bariatric surgery. This prevalence does not increase after AGB while it rises up to 40 % of patients after RYGBP and it is associated with lower weight loss.

"Candy cane syndrome:" an underappreciated cause of abdominal pain and nausea after Roux-en-Y gastric bypass surgery

BACKGROUND

"Candy cane" syndrome (a blind afferent Roux limb at the gastrojejunostomy) has been implicated as a cause of abdominal pain, nausea, and emesis after Roux-n-Y gastric bypass (RYGB) but remains poorly described.

OBJECTIVES

To report that "candy cane" syndrome is real and can be treated effectively with revisional bariatric surgery SETTING: All patients underwent "candy cane" resection at University Hospitals of Cleveland.

METHODS

All patients who underwent resection of the "candy cane" between January 2011 and July 2015 were included. All had preoperative workup to identify "candy cane" syndrome. Demographic data; pre-, peri-, and postoperative symptoms; data regarding hospitalization; and postoperative weight loss were assessed through retrospective chart review. Data were analyzed using Student's t test and χ² analysis where appropriate.

RESULTS

Nineteen patients had resection of the "candy cane" (94% female, mean age 50±11 yr), within 3 to 11 years after initial RYGB. Primary presenting symptoms were epigastric abdominal pain (68%) and nausea/vomiting (32%), particularly with fibrous foods and meats. On upper gastrointestinal study and endoscopy, the afferent blind limb was the most direct outlet from the gastrojejunostomy. Only patients with these preoperative findings were deemed to have "candy cane" syndrome. Eighteen (94%) cases were completed laparoscopically. Length of the "candy cane" ranged from 3 to 22 cm. Median length of stay was 1 day. After resection, 18 (94%) patients had complete resolution of their symptoms (P<.001). Mean body mass index decreased from 33.9±6.1 kg/m² preoperatively to 31.7±5.6 kg/m² at 6 months (17.4% excess weight loss) and 30.5±6.9 kg/m² at 1 year (25.7% excess weight loss). The average length of latest follow-up was 20.7 months.

CONCLUSION

"Candy cane" syndrome is a real phenomenon that can be managed safely with excellent outcomes with resection of the blind afferent limb. A thorough diagnostic workup is paramount to proper identification of this syndrome. Surgeons should minimize the size of the blind afferent loop left at the time of initial RYGB.

Asymptomatic gastric bacterial overgrowth after bariatric surgery: are long-term metabolic consequences possible?

BACKGROUND

Patients with postbariatric bacterial overgrowth were reinvestigated after a follow-up of 15 years. It was hypothesized that systemic associations analogous to those reported for whole gut microbiome would be revealed.

METHODS

Patients (n = 37, 70.3 % females, 42.4 ± 9.9 years old, preoperative BMI 53.5 ± 10.6 kg/m(2), current BMI 32.8 ± 10.8 kg/m(2)), all submitted to RYGB on account of morbid obesity, were followed during 176.8 ± 25.7 months. Blood tests included fasting blood glucose, HbA1c, liver and pancreatic enzymes, and lipid fractions. Bacterial overgrowth was diagnosed by quantitative culture of gastric fluid in both the excluded remnant and the gastric pouch, with the help of double-balloon enteroscopy. Absolute counts of aerobes and anaerobes in both gastric reservoirs were correlated with nutritional and biochemical measurements, aiming to identify clinically meaningful associations.

RESULTS

Patients denied diarrhea, abdominal pain, weight loss, or other symptoms related to bacterial overgrowth. Biochemical profile including enzymes was also acceptable, indicating a stable condition. Positive correlation of bacterial count in either segment of the stomach was demonstrated for BMI and gamma-glutamyl transferase, whereas negative correlation occurred regarding fasting blood glucose.

CONCLUSIONS

An antidiabetic role along with deleterious consequences for weight loss and liver function are possible in such circumstances. Such phenotype is broadly consistent with reported effects for the whole gut microbiome. Prospective controlled studies including molecular analysis of gastrointestinal fluid, and simultaneous profiling of the entire microbiome, are necessary to shed more light on these findings.

Prevalence and co-occurrence of upper and lower functional gastrointestinal symptoms in patients eligible for bariatric surgery

BACKGROUND

Obesity is considered as a risk factor for many functional digestive disorders. The aim of the present study was to evaluate the prevalence and the association of functional digestive symptoms affecting the upper and the lower digestive tract in patients eligible for bariatric surgery.

METHODS

Before surgery, 120 consecutive patients with normal upper endoscopy (7.5% males, mean BMI 44 ± 6 m/kg(2)) have filled a standard questionnaire in order to evaluate the presence of depressive symptoms and functional digestive disorders according to the Rome criteria. The major symptoms (esophageal, gastroduodenal, anorectal, and abdominal pain) were coded as dichotomous variables. Data analysis was performed using multivariate logistic regression with a backwards selection procedure adjusted only for the variables that were significant in univariate analysis (p < 0.05).

RESULTS

Functional symptoms were present in 89% of the subjects (2.5 functional digestive symptoms/subject). Depression symptoms were found in 43% of the patients. Esophageal symptoms were independent predictors for the presence of gastric, bowel, and anorectal symptoms. Functional abdominal pain and bowel symptoms were present, respectively, in 19% and 84% of the patients. Approximately half of the patients have specific functional bowel disorders (28.6% constipation, 18% irritable bowel syndrome, 18% diarrhea, 1% bloating) and 35.7% have non-specific bowel disorders. Anorectal symptoms were found in 40% of the patients: difficult defecation in 32% and fecal incontinence in 9.8% of the patients. Depression was an independent predictor for anorectal symptoms.

CONCLUSIONS

This study shows the high prevalence of functional bowel symptoms in patients complaining of morbid obesity.

What every hospitalist should know about the post-bariatric surgery patient

Obesity is a growing worldwide epidemic, increasingly addressed through surgical options for weight loss. Benefits of these operations, such as weight loss and improvement or reversal of obesity-related comorbidities, are well established; however, postoperative complications do occur. This article will evaluate common causes for hospital admissions in the post-bariatric surgery population as they relate to the hospitalist who is often responsible for their care. Here we provide an overview of the most common bariatric procedures currently performed, early postoperative complications, late medical complications (ie, abdominal complaints, weight fluctuations, nutritional deficiencies, and metabolic bone disease), and late surgical complications that often affect these patients and result in hospital admissions. Special attention will be paid to radiologic pearls that can assist in the initial evaluation and diagnosis of these patients.

Abdominal pain after gastric bypass: suspects and solutions

BACKGROUND

Gastric bypass remains the mainstay of surgical therapy for obesity. Abdominal pain after gastric bypass is common and accounts for up to half of all postoperative complaints and emergency room visits. This article reviews the most important causes of abdominal pain specific to gastric bypass and discusses management considerations.

METHODS

The current surgical literature was reviewed using PubMed, with a focus on abdominal pain after gastric bypass and the known pathologies that underlie its pathogenesis.

RESULTS

The etiologies of abdominal pain after gastric bypass are diverse. A thorough understanding of their pathogenesis impacts favorably on clinical outcomes.

CONCLUSIONS

The differential diagnosis for abdominal pain after gastric bypass is large and includes benign and life-threatening entities. Its diverse causes require a broad evaluation that should be directed by history and clinical presentation. In the absence of a clear diagnosis, the threshold for surgical exploration in patients with abdominal pain after gastric bypass should be low.