Afferent Limb Obstruction: Diagnosis and Management

Abstract

The afferent limb lies upstream of the gastrojejunostomy and drains biliary, pancreatic and intestinal secretions. Afferent limb obstruction (ALO) is a rare and difficult to diagnose complication following pancreaticoduodenectomy. Causes of ALO include volvulus, internal herniation, intussusception and recurrent malignancy. Herein we report a case of ALO secondary to recurrent pancreatic malignancy presenting as ascending cholangitis three years following pancreaticoduodenectomy. An 81 year old male with past medical history of pancreatic adenocarcinoma status post Whipple pancreaticoduodenectomy presented with fever (102.1 F), icterus and right upper quadrant abdominal pain. Laboratory work-up demonstrated elevated bilirubin (2.7 mg/dL), alkaline phosphatase (478 U/L), AST (97 U/L), ALT (172 U/L) and vancomycin resistant enterococcus faecalis (VRE) bacteremia. Marked afferent limb distention was noted on CT scan. MRCP demonstrated a dilated afferent limb with a transition point at the biliary-enteric anastomosis as well as extrahepatic biliary and pancreatic duct dilation. A percutaneous trans-hepatic biliary drain was placed. Cholangiography demonstrated passage of the drain through the biliary-jejunal anastomosis into the efferent limb with contrast accumulation in the afferent limb, suggestive of ALO. Intraoperative bile cultures returned positive for VRE and klebsiella oxytoca. PET scan showed an FDG avid area at the pancreatic-jejunal anastomosis suspicious for local recurrence. CA 19-9 was significantly elevated (720 U/ml). Overall these findings were consistent with ALO secondary to recurrent pancreatic malignancy infringing the biliary-enteric anastomosis. Cholangiography later confirmed a tumor fungating into the CBD. ALO is an open loop mechanical obstruction that can present as peritonitis, perforation, pancreatitis, or ascending cholangitis. Diagnosis is made radiographically. Classic findings of ALO on upper GI barium studies are non-filling of the afferent loop or in-loop contrast retention. Now the presence of a C-loop (fluid filled afferent limb) or keyboard sign (mucosal folds) on CT are considered characteristic of ALO. Management of neoplastic ALO is focused on palliative percutaneous or endoscopic interventions to relieve the obstruction. This case highlights the importance of multimodality imaging in the diagnosis of ALO and the role of interventional radiology in symptom palliation.