Afferent Loop Syndrome Masquerading as Recurrent Acute Pancreatitis

Abstract

Introduction Afferent loop syndrome (ALS) is a rarely described complication following gastric-bypass surgery and the creation of gastro-jejunostomy. We present a case of this disorder mimicking recurrent acute pancreatitis. Case presentation A 67 yr old Caucasian F underwent Roux-en-Y gastric bypass in 2012. Initially had good weight loss and no post-operative complications. In 2017, began to develop recurrent episodes of epigastric/RUQ pain, N/V. CT scan showed cholelithiasis and internal hernia. Labs were all normal, including CBC, hepatic function, and lipase. She underwent cholecystectomy and hernia repair. Patient continued to have pain, but this time with lipase greater than 3 times the upper limit of normal concerning for pancreatitis. MRCP was normal except mildly dilated CBD, however CT showed dilated loops of small bowel in pelvis. Repeat surgical exploration was performed with extensive lysis of adhesions. Patient continued to have intermittent pain with elevation of lipase concerning for pancreatitis. Autoimmune pancreatitis was ruled out. Given dilated CBD and increasing ALP, there was concern for SOD type 1. Lap assisted ERCP was performed which showed papillary stenosis and was treated with dual sphincterotomy. Following ERCP patient did well for about 1 month until similar pain led to repeat hospitalization. Lipase was elevated as well. CT showed significantly dilated duodenum and remnant stomach concerning for afferent loop syndrome. Patient underwent revision of jejunostomy with biliopancreatic limb being re-anastomosed 10cm distal to prior site with 10cm long anastomosis to prevent recurrence. Following this procedure patient had complete resolution of symptoms. Discussion ALS is a consequence of partial or complete obstruction of the gastrojejunostomy along the jejunal portion of the afferent limb. Passage of food and gastric secretions through the gastrojejunostomy and into the efferent loop triggers the release of secretin and cholecystokinin, which in turn stimulate secretion of upto 1-2 L of pancreatic and biliary secretions into the afferent loop each day. Symptoms are usually caused by increased intraluminal pressure and distention due to accumulation of these secretions in an obstructed afferent limb. This can present as obstructive jaundice, ascending cholangitis, and pancreatitis. Our case serves to highlight the importance of taking a multi-disciplinary approach to these complicated patients with ongoing abdominal pain.1384_A.tif Figure 1: No Caption available.1384_B.tif Figure 2: No Caption available.