PMC9844955_01
Computed tomography scan (portal venous phase post intravenous contrast) showing a short segment of thickened, enhancing terminal ileum consistent with terminal ileitis of CD.
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Contrast-enhanced computed tomography (CT) of the abdomen and pelvis showed a short segment of acute inflammation of the terminal ileum (Fig. 1) and an incidental right adnexal cyst.
Magnetic resonance enterography demonstrating strictures of the small bowel (A) in a segment of terminal ileitis with acute inflammation (B).
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Magnetic resonance enterography confirmed stricturing CD with two segments of inflammation of the terminal ileum (lengths of 5 and 3.8 cm) approximately 5 cm from the ileocaecal valve (Fig. 2). 
Histopathological findings in CD; (A) H&E section (x20 magnification) showing fissuring ulceration, focal cryptitis, crypt abscess and background smooth muscle hypertrophy; (B) H&E section (x40 magnification) showing submucosal lymphoid aggregates and plasma cells; (C) H&E section (x200 magnification) showing Paneth cell metaplasia (arrows); (D) H&E section (x100 magnification) showing Nerve twig hypertrophy (arrows) at the base of the ulcer.
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Histopathology confirmed stricturing CD:with acute on chronic inflammation, fissuring ulcer formation, reactive epithelial hyperplasia, chronic inflammatory change and smooth muscle hypertrophy (Fig. 3).
Histopathological findings in endometriosis; (A) H&E section (x20 magnification) showing endometriotic foci (arrows) within the muscularis propria, terminal ileal mucosa is seen in the top right corner; (B) H&E section (x100 magnification) showing a magnified view of an endometriotic focus which comprises of ectopic endometrial glands (yellow arrows) surrounded by ectopic endometrial stroma (black arrows); focal haemosiderin-laden macrophages are also present in the background of ectopic endometrial stroma.
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A second distinct stricture confirmed an endometriotic deposit in the muscularis externa and submucosa with associated haemosiderin-laden macrophages (Fig. 4).