Parasitic infestation in appendicitis. A retrospective analysis of 660 patients and brief literature review.

To investigate the incidence of parasitic infestations and inflammation accompanying parasitosis in a series of appendectomy cases.  Methods: Six-hundred-sixty  patients who had undergone appendectomy in Bingöl State Hospital, Bingol, Turkey with the preliminary diagnosis of appendicitis between January 2012 and February 2015 were included in this retrospective study. They were retrospectively evaluated in terms of age, gender and pathological findings. Cases diagnosed with parasitic infestations were re-evaluated histopathologically for inflammatory response.  Results: The mean age was 19.6 years, and the male/female ratio was 1.8. When evaluated in terms of histopathological diagnoses, 573 (86.8%) were diagnosed as acute appendicitis, and parasitic infestation was identified in 12 (1.8%). Among cases with parasitic infestation, Enterobius vermicularis was identified in 9 (75%) and Taenia in 3 (25%) cases. Of cases with Enterobius vermicularis, 4 (44.4%) had lymphoid hyperplasia, 1 (11.1%) had normal-structured appendix vermiformis, and 4 (44.4%) had findings of acute appendicitis. All cases with taeniasis had an inflammatory response: acute appendicitis was identified in 2 (66%) and acute gangrenous appendicitis in 1 (33%) of them.  Conclusion: Parasitic infestations are among the probable causes in appendicitis etiology and should be kept in mind during differential diagnosis. However, whether every parasitic infestation leads to appendiceal inflammatory response is controversial.