Crohn's disease mistaken for long-standing idiopathic mesenteric panniculitis: A case report and management algorithm

BACKGROUND: Mesenteric panniculitis (MP) is mostly an associated sign of an intra-abdominal or systemic inflammatory primary disease. Nevertheless, etiological and differential diagnosis of idiopathic MP can be challenging when an associate primary cause is not in the foreground. Methods: We report here the case of an isolated small bowel Crohn's disease, long time considered as idiopathic MP. RESULTS: This patient presented to our department with a 10-year history of acute abdominal symptoms evolving with flare-up and remission. A diagnosis of idiopathic MP was made based on compatible CT-scan features along with normal laboratory tests and upper and lower bowel endoscopies. As symptoms recurred, a steroid course was proposed which dramatically improved his condition for years. Finally, an explorative laparoscopy was performed because of concern of malignancy when he returned to our unit with a steroid refractory flare-up and weight loss, along with MP nodes growing up to 10 mm. Crohn's disease was eventually diagnosed, based on histopathological middle-gut bowel resection and numerous granulomas in mesenteric nodes without necrosis. CONCLUSION: This case emphasizes the importance of excluding inflammatory intestinal lesions before making the diagnosis of idiopathic MP (fecal calprotectin, magnetic resonance enterography, wireless capsule endoscopy).