Pancreatic Exocrine Insufficiency Years After Bariatric Surgery: Clinical Insights From 2 Cases

BACKGROUND Bariatric surgery has been established as an effective intervention for significant and sustained weight loss in morbidly obese individuals. Roux-en-Y gastric bypass (RYGB) is a widely performed procedure that alters the gastrointestinal anatomy. A common symptom after bariatric surgery is diarrhea, which can be caused by several factors. A rare cause of diarrhea following RYGB is pancreatic exocrine insufficiency (PEI), which is often underrecognized in post-bariatric patients. While commonly associated with pancreatic diseases, PEI can also occur as a complication following bariatric surgeries such as RYGB. This report aims to raise awareness of delayed-onset PEI as a potential cause of chronic gastrointestinal symptoms in long-term RYGB patients and highlights the need for clinical vigilance to prevent unnecessary interventions and prolonged malnutrition. CASE REPORT We present 2 cases in which delayed-onset PEI developed several years after undergoing RYGB. Case 1 was a woman in her 40s who underwent RYGB. Seven years after surgery, she presented with unexplained severe diarrhea and progressive weight loss, from an initial BMI 28 kg/m² to 15.8 kg/m², in just a few months. Her fecal elastase level was 77 μg/g. She was successfully treated with pancreatic enzyme replacement treatment (PERT). Case 2 was a woman in her 50s with a history of RYGB 10 years prior, with an initial BMI of 46 kg/m2. She was evaluated for persistent diarrhea and left-sided abdominal pain, which had been ongoing for 6 months. Abdominal CT suggested adhesions around the jejuno-jejunostomy, and laparoscopic adhesiolysis was performed, but her symptoms persisted unchanged. Postoperatively, fecal elastase-1 testing confirmed the suspicion of PEI, and she was successfully treated with PERT. CONCLUSIONS Although PEI is a recognized complication of bariatric surgery, it is challenging to diagnose and treat due to limited awareness. This case report shows the importance of recognition and management of delayed-onset PEI following RYGB.