Acute amebic appendicitis.

Introduction: Acute appendicitis of amebic origin is considered a rare cause of acute appendicitis.

Methods: The clinical notes for 4093 patients over the age of 16 who had undergone appendectomy were reviewed. Particular attention was paid to the histopathologic results, separating out those cases where trophozoites were seen in the appendix. These cases were considered to be of amebic origin.

Results: A total of 93 cases reported lesions suggestive of amebiasis (2.3%). This study analyzed 86 of these cases. Comparing the cases in this study against the cases of patients with acute appendicitis in general (excluding the cases of amebic origin), no differences were found in relation to the distribution or presentation according to sex or in the degree of inflammation of the appendix, the incidence of surgical wound infection, or general complications. By contrast, the study noted a statistically significant difference in the age at presentation: Acute appendicitis of amebic origin presents principally among those under 20 years of age and is accompanied by a higher frequency of fecal fistula (2.3%).

Conclusions: Acute appendicitis of amebic origin is not seen frequently, and in general it does not behave any differently from other cases of acute appendicitis, except in its earlier presentation and its greater incidence of fecal fistula. The condition is suspected clinically whenever a cecum of hard, "cardboard-like" consistency is discovered.