J Korean Soc Radiol.  2014 Jun;70(6):430-434. 10.3348/jksr.2014.70.6.430.

Two Cases of Fibrous Obliteration of the Appendix, Mimicking Acute Appendicitis

• Choi SJ
• Jang YJ
• Lee D
• Cho SH
• Kim GC
• Bae JH
• Park JY
• Cheon JM

• KMID: 1941771
• DOI: http://doi.org/10.3348/jksr.2014.70.6.430

Abstract

Acute appendicitis is the most frequent appendiceal disease, but some chronic inflammatory conditions can mimic it on computed tomography (CT). We recently experienced two rare cases of appendiceal conditions, which were uncommon to our radiologists and clinicians. This condition is called fibrous obliteration of the appendix, which is a condition that involves replacement of the mucosa and submucosa with fibrotic tissues. Due to similar clinical symptoms and CT findings, fibrous obliteration of the appendix can easily be mistaken as an acute appendicitis. Here, we introduce the symptoms, laboratory results, CT findings, and histological examination findings of two adult patients with fibrous obliteration of the appendix.

MeSH Terms

Adult
Appendicitis*
Appendix*
Humans
Mucous Membrane

Figure

• 

  Fig. 1 Computed tomography (CT) findings and pathological images of fibrous obliteration in the appendix of a 63-year-old man. A. Coronal CT scan shows borderline dilatation of the appendix filled with a fatty component (-33 Hounsfield unit). A focal wall defect in the distal portion of the appendix and an adjacent mild fatty infiltration (arrowheads) is visible. B. Coronal CT scan shows the linear-enhancing core of the appendix (arrows). C, D. Photomicrographs of a histopathological specimen in longitudinal (C) and cross-sectional (D) view of the distal appendix [hematoxylin and eosin stain, × 1.25 (C, D-left), × 200 (D-right)] show adipocyte and fibroblast proliferation filling the appendiceal lumen and focal destruction of the mucosa (or ragged mucosa). Several arterioles are visible in the center. The suspicious focal wall defect on the CT scan was not visible in the histopathological specimen.

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  Fig. 2 Computed tomography (CT) findings of fibrous obliteration in the appendix of a 43-year-old woman. A. Axial CT scan shows periappendiceal infiltration (arrowhead) and a linear-enhancing core structure (arrow). B. Coronal CT scan shows periappendiceal infiltration (arrowhead). Note the thickened appendiceal wall and dilated lumen.

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