S3532 Groove Pancreatitis Imitating Hypertriglyceridemic Pancreatitis: Unraveling a Diagnostic Dilemma

Introduction: Groove pancreatitis (GP) is a rare form of pancreatitis affecting the anatomical space between the head of pancreas, the duodenum and the common bile duct. It is often under-recognized and presents a diagnostic challenge. It is typically seen in middle aged males with heavy alcohol and tobacco use however it can affect even younger patients without classic risk factors. This case is presented to raise awareness of GP and encourage its inclusion in patients with atypical presentations of pancreatitis. Case Description/Methods: A 31-year-old man with type 2 diabetes, hypertension, and hyperlipidemia presented with a 2 week-history of worsening epigastric pain aggravated by food intake along with nausea and vomiting. He was not on any medications and vitally stable on presentation. Computed tomography abdomen revealed acute pancreatitis with 2 small focal areas of hypoattenuation concerning for necrosis along with inflammatory haziness and fluid in the pancreaticoduodenal groove. He was admitted and managed conservatively. Further work up showed triglycerides of 687 mg/dl and normal IgG4 level. Given the computed tomography findings suggestive of GP, an magnetic resonance imaging abdomen was obtained which showed distended stomach and duodenum with abnormal thickening of the third part of the duodenum and mild edema along the uncinate process of the pancreas—findings consistent with GP. The patient was started on fenofibrate and atorvastatin. He improved clinically, tolerated diet advancement and triglyceride levels trended down. He was discharged in stable condition with insulin counseling and outpatient GI follow-up. Discussion: The diagnosis of GP is challenging due to overlapping features with other pancreatic conditions. Initial computed tomography imaging raised suspicion for GP, prompting further evaluation with magnetic resonance imaging, which confirmed findings consistent with the diagnosis. Concurrently, the patient’s elevated triglyceride level introduced hypertriglyceridemia as another possible etiology contributing to a mixed clinical picture. Given this overlap and despite the presence of hypertriglyceridemia, imaging was pursued to evaluate for GP based on suggestive computed tomography findings. This case highlights the importance of considering GP in the differential diagnosis in patients particularly when clinical and imaging features deviate from the expected course.