Exocrine pancreatic insufficiency after bariatric surgery: a bariatric surgery center of excellence experience

Abstract

Introduction: Gastrointestinal symptoms such as diarrhea, bloating, abdominal pain, and nausea are common after bariatric surgery (BS) and can lead to significant morbidity. While many diagnoses can explain these symptoms, post-bariatric exocrine pancreatic insufficiency (EPI) is becoming increasingly recognized as contributor to gastrointestinal symptoms. The frequency and outcomes of EPI after BS are not well understood. We investigated the prevalence and outcomes of EPI over 18 years at a tertiary bariatric referral center.

Methods: A retrospective review of patients who underwent primary or revisional BS from 2002 to 2020 was performed. Patients were included if they were suspected of having EPI or underwent fecal elastase testing (FE-1). EPI diagnosis was defined as positive FE-1 testing or improvement with empiric pancreatic enzyme replacement therapy (PERT).

Results: EPI was suspected in 261 patients, and 190 were tested via FE-1 (89.5%) or empirically treated (10.5%). EPI was diagnosed in 79 (41.6%) patients and was associated with older age and lower BMI. Therapeutic PERT was given to 65 patients diagnosed with EPI, and 56 (86.2%) patients reported improved symptoms. Patients who underwent RYGB and BPD-DS were more likely to have EPI than those after SG (47.9% and 70.0% vs 17.4%, p < 0.01). EPI diagnosis was associated with a history chronic pancreatitis. While diarrhea and abdominal pain were the most common symptoms prompting FE-1 testing, no symptoms were significantly associated with EPI. EPI was also associated with abnormal fecal fat results and treatment with bile acid sequestrants, but not small intestinal bacterial overgrowth.

Conclusion: This study highlights that exocrine pancreatic insufficiency can account to for previously unexplained GI complaints after bariatric surgery. Therefore, bariatric surgery programs should consider this diagnosis in symptomatic patients, especially following RYGB and BPD-DS. Further work to define patient factors that should prompt evaluation, optimal treatment, and prevention is necessary.

Keywords: Bariatric surgery; Exocrine pancreatic insufficiency; Pancreatic enzyme replacement therapy; Roux-en-Y gastric bypass; Small intestinal bacterial overgrowth.