Post-ischemic enteritis mimicking Crohn's disease with complex entero-enteric fistulization

Mesenteric venous thrombosis is an uncommon yet potentially life-threatening cause of mesenteric ischemia with an insidious clinical course. Delayed diagnosis of venous ischemia may lead to late complications such as bowel strictures, perforation, and fistulization. These sequelae can closely mimic Crohn's disease, posing significant diagnostic and therapeutic challenges. We report the case of a 33-year-old postpartum woman who presented with acute abdominal pain and was diagnosed with subacute thrombosis of the superior mesenteric vein and portal vein confluence on contrast-enhanced CT. Initial imaging demonstrated jejunal wall thickening without signs of transmural necrosis, and the patient was managed conservatively with anticoagulation. Despite treatment, she later developed recurrent abdominal pain, bowel obstruction, perforation, and complex small bowel fistulization. Serial imaging findings were initially interpreted as fibrostenotic Crohn's disease. Endoscopic evaluation and bowel biopsies were unremarkable. Ongoing recurrent obstruction ultimately necessitated limited small bowel resection, and histopathologic findings confirmed ischemic injury, characterized by ulceration, vascular congestion, granulation tissue, and full-thickness hyalinization and necrosis. The patient unfortunately died from postoperative complications seven months after the initial presentation. This case highlights chronic ischemic enteritis as an important masquerader of Crohn's disease, particularly in patients with a history of mesenteric venous thrombosis. Complex fistulization and fibrostenotic changes are not pathognomonic for inflammatory bowel disease and may represent late sequelae of missed or patchy bowel ischemia. Careful assessment of mesenteric vasculature and collateral formation on imaging is crucial to avoid misdiagnosis, inappropriate immunosuppressive therapy, and delayed definitive management.