Misdiagnosis of Crohn's disease as appendicitis: A case report.

Background: Crohn's disease (CD) is a chronic inflammatory disease of the intestinal tract that can alternate between disease phases and remission. Currently, endoscopy is the gold standard for diagnosis of CD and evaluation of its activity and complications. However, gastrointestinal ultrasound (GIUS) is a valuable technique in the management of CD because it is noninvasive, convenient, and highly accurate, sensitive, and specific.

Case summary: A 15-year-old female presented with recurrent right lower quadrant abdominal pain that had persisted for 2 weeks. Initial GIUS and computed tomography revealed significant edema of the appendix and ascending colon wall, thickening, and multiple lymphadenopathies of the mesentery. Clinicians suspected appendicitis involving the adjacent bowel, and laparoscopic appendectomy was performed. The pathological diagnosis was acute simple appendicitis. However, the patient's symptoms persisted and aggravated with the occurrence of hematochezia. Follow-up GIUS revealed persistent edema of the ascending and transverse colon walls, intestinal polyps, and local luminal stenosis. CD was suspected and confirmed by endoscopy.

Conclusion: CD should be suspected with persistent right lower quadrant abdominal pain. GIUS is essential for initial evaluation, before the confirmatory endoscopy, to assess CD-typical signs like bowel edema and thickening.