Appendiceal Diverticulitis Mimics Cecal Diverticulitis Diagnosed Preoperatively

Abstract

Appendiceal diverticulitis is an uncommon condition that clinically resembles acute appendicitis. However, it is an incidental finding in histopathological studies and is rarely diagnosed preoperatively by imaging studies. In this article, we present the clinical and imaging findings of a male patient presenting with right upper quadrant pain with a preoperative imaging diagnosis of appendiceal diverticulitis. He underwent laparoscopic appendectomy and confirmed the diagnosis of appendiceal diverticulitis. This is a rare preoperative diagnosis. The management is often like typical appendicitis which is appendectomy. It is important to differentiate it from diverticulitis of the small intestine or colon because these diseases usually require only conservative treatment.

Keywords: Appendiceal diverticulitis; computed tomography; diverticular disease; laparoscopic appendectomy; pathology.

Figure 1.

(A) Gray-scale ultrasound image showed an inflamed appendiceal diverticulum containing feces (asterisk), with surrounding fatty infiltration (curved arrow). (B) Oblique sagittal plane CT image shows an enlarged appendix (dashed line) with several fecal-containing diverticula (asterisk) and surrounding fatty infiltration (curved arrow). Note that the root (red arrowheads), and the body and tip of the appendix (straight arrows) were normal size. (C) Image taken during laparoscopic appendectomy showed an enlarged appendix with a red inflamed diverticular surface (asterisk). (D-F) Surgical specimen showed normal appendicular root (red arrowheads) and body (yellow open arrows), appendiceal diverticulitis (asterisks), congested superficial blood vessels (black solid arrows), and appendiceal diverticulum hole (circle).

Figure 2.

Microscopic images of the appendix specimen with diverticula (hematoxylin-eosin stain). (A) There was infiltration of acute inflammatory cells into the diverticular mucosa (arrows). (B) Appendiceal mucosa was infiltrated with plasma cells (blue circle), polymorphonuclear leukocytes (green circles), and eosinophils (yellow circle). (C) Diverticulum mucosa was infiltrated with plasma cells (blue circle), eosinophils (yellow circle), neovascularization (green arrows), and fibrous hyperplasia (red double-headed arrow). (D) Appendiceal diverticula had thin muscle layer (yellow double-headed arrow).