Unusual histopathologic findings in appendectomy specimens of acute appendicitis cases: Appendiceal parasites and tumors

Abstract

The aim of this study was to document unusual findings in the pathologic evaluation of appendectomy specimens, evaluate appendiceal tumors, and assess the role of parasites in the etiology of acute appendicitis. The clinical and histopathologic data of patients who underwent appendectomy for acute appendicitis at Sanliurfa Training and Research Hospital between January 2016 and October 2023 were retrospectively analyzed. Incidental appendectomies performed during other operations were excluded. Histopathologically unusual findings were found in the appendectomy material of 117 (2.6%) of the 4449 patients included in the study. Parasitic agents were found in 49 cases (1.10%) and malignant appendix tumors were found in 19 cases (0.43%). The tumors were predominantly distally located (63.16%) and the tumor types were predominantly neuroendocrine tumors (57.89%). Parasitic agents (mean age: 12.7±10.02 years) were observed at an earlier age than appendix tumors (mean age: 35.0±17.06 years). There was no statistical difference between the C-reactive protein (CRP), eosinophil (EO) and white blood count (WBC) values of patients with parasitic agents and patients with tumors. Additionally, in one patient’s appendix, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), which is considered very rare in the literature, was detected. Parasites such as Enterobius vermicularis, Taenia spp. and Ascaris lumbricoides should be considered in cases of acute appendicitis, especially in children in endemic areas such as Sanliurfa. Although malignant tumors of the appendix are rare, histologic examination after appendectomy should be performed for the diagnosis and treatment of tumors. On the other hand, we recommend CRP levels to be examined in patients diagnosed with acute appendicitis.

Keywords

• Appendicitis
• carcinoid
• Enterobius vermicularis

Ethical Statement

Approval for the study was obtained from Harran University Clinical Research Ethics Committee (HRÜ/23.03.24).

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