Parasitological and histopathological features of appendectomy specimens in Fars Province, southern Iran: a retrospective study

Abstract

Background: Although the appendix is the most commonly resected and examined intra-abdominal organ, the pathogenesis and etiology of acute nonspecific appendicitis remain enigmatic. This retrospective study aimed to assess the prevalence of parasitic infection in surgically removed appendices and to evaluate the probable associations between the presence of parasites and the occurrence of appendicitis through parasitological and histopathological examinations of the appendectomy specimens. Materials and methods: This retrospective study was carried out from April 2016 to March 2021 among all patients referred to hospitals affiliated with Shiraz University of Medical Sciences, Fars Province, Iran, for appendectomy. Patient information, including age, sex, year of appendectomy, and type of appendicitis, was collected from the available data in the hospital information system database. In positive cases, all pathology reports were retrospectively evaluated for the presence of the parasite and its type, and analytical and descriptive statistics were carried out using SPSS software version 22. Results: A total of 7628 appendectomy materials were evaluated in the present study. Of the total participants, 4528 (59.4%, 95% CI: 58.2–60.5) were males, and 3100 (40.6%, 95% CI: 39.5–41.8) were females. The mean age of participants was 23.87±14.28 years. Overall, Enterobius vermicularis was observed in 20 appendectomy specimens. Fourteen of these patients (70%) were less than 20 years old. Conclusion: This study indicated that E. vermicularis is one of the common infectious agents that could be found in the appendix and may increase the risk of appendicitis. Therefore, in terms of appendicitis, clinicians, and pathologists must be aware of the possible presence of parasitic agents, especially E. vermicularis, to treat and manage the patients sufficiently.

<em>Enterobius Vermicularis</em> Related Acute Appendicitis: A Case Report and Review of the Literature

“…The head section is rounded which contains the esophagus, which is muscular and the bulb, the tail section in the females is narrow and tapered sharply. The fertilized female worm has a very extensive uterine reproductive system which when completely filled with eggs, can contain over 10,000 eggs per worm [7].…”

“…Using readily available adhesive tape, with buttocks spread apart, one can press a small strip several times to the anal and perianal region. Then the worm eggs are then able to be identified microscopically by affixing the tape, adhesive side down, to a slide [7].…”

“…Autoinfection or transmission may occur as a result of scratching because the action itself releases eggs which can easily stick to the fingers or under the fingernails and be passed on. In some rare cases, pinworms can be indirectly responsible for vulvovaginitis -irritation/inflammation of the area -if pinworms migrate to the vaginal are and this could also indirectly cause a urinary tract infection as other enterobacteria like Escherichia coli can adhere [7]. Pinworm infestation is also considered to be the most common helminthic infection found in the appendiceal lumen -the inside of the appendix -and has been said to cause acute appendicitis.…”

“…The role of E. vermicularis in relation to the pathogenesis of few cases of acute appendicitis has been the subject of controversy for many years, as pinworms have been discovered in the appendix as far back as 1634 by Fabrius [7,8] despite the fact that no causality has been reliably demonstrated. The majority of the cases reported has mainly been in the pediatric population.…”

Enterobius vermicularis Related Acute Appendicitis: A Case Report and Review of the Literature

“…The role of E. vermicularis in relation to the pathogenesis of a few cases of acute appendicitis has been the subject of controversy for many years, as pinworms have been discovered in the appendix as far back as 1634 by Fabrius [ 7 , 8 ], despite the fact that no causality has been reliably demonstrated. The majority of the cases that have been reported so far has mainly been in the pediatric population.…”