86 Stomach Trouble With a Twist: Crohn’s Disease in Disguise

Background: Upper gastrointestinal Crohn’s disease (UGI-CD), defined as involvement proximal to the ligament of Treitz, is an uncommon manifestation, reported in 0.3%–14% of patients. Because presentations are often asymptomatic or nonspecific, UGI-CD is easily overlooked and can mimic peptic ulcer disease, gastrinoma, infection, or malignancy, leading to diagnostic delay. We report a patient who presented with extensive upper GI ulcerations initially raising concern for alternative etiologies, but who was ultimately diagnosed with small-bowel Crohn’s disease. Case Presentation: A 48-year-old woman presented to the emergency room with progressive right upper quadrant and epigastric pain requiring multiple emergency room visits for symptom control. Initial work up included computed tomography of the abdomen which showed gastritis, duodenitis, and antral wall thickening. Laboratory studies revealed leukocytosis to 20.44 K/µL, elevated C-reactive protein (7.82 mg/dL), and increased erythrocyte sedimentation rate (55 mm/hr). An EGD demonstrated diffuse large distal gastric, duodenal, and jejunal ulcers, raising concern for a gastrinoma. Biopsies showed moderate acute and chronic gastritis and were negative for Helicobacter pylori. Endoscopic ultrasound revealed no intrapancreatic or biliary lesions; lymph node biopsies were negative for malignant cells. Her serum gastrin level was normal at 14 pg/mL. Extensive serologic evaluation for rheumatologic and malignant causes of her symptoms was unrevealing. Despite lack of lower gastrointestinal symptoms, her fecal calprotectin was found to be elevated at 3,000 μg/g. Magnetic resonance enterography revealed a long segment of abnormal enhancement and thickening of the ileum. Colonoscopy with ileal intubation showed patchy inflammation with ulcerations in the distal ileum and stenosis 70 cm from the ileocecal valve. Biopsies demonstrated mild to moderate active ileitis with granulation tissue and infectious stains were negative. Random colon biopsies showed no pathologic alteration. After over one year of extensive work up, given the ongoing inflammatory changes and ileal stricturing, a presumptive diagnosis of small bowel Crohn’s disease was made. She was started on intravenous methylprednisolone with significant improvement in her symptoms and was subsequently transitioned to infliximab therapy for steroid-sparing treatment. Discussion: This case highlights the diagnostic challenges of UGI-CD, which often presents with nonspecific symptoms and nondiagnostic biopsy findings. Endoscopically, UGI-CD may manifest as nodularity, linear ulcerations, or strictures, but histology is frequently nonspecific; granulomas, gastritis, or focal cryptitis are seen in only a minority of cases. As a result, patients frequently undergo prolonged evaluation involving multiple imaging studies, endoscopies, and serologic tests before diagnosis is established. Because UGI-CD carries a more aggressive clinical course than colonic Crohn’s, with earlier progression and greater need for intensive therapy, timely recognition is essential. However, diagnosis is often delayed compared with ileocolonic disease due to the broad differential for upper GI ulceration and the absence of standardized diagnostic criteria. This case illustrates how UGI-CD can masquerade as other conditions and underscores the importance of maintaining a high index of suspicion in patients with unexplained upper GI findings.