Incidental parasitic infestations in surgically removed appendices: a retrospective analysis

Abstract

Background: Appendiceal parasites can cause symptoms of appendiceal pain, independent of microscopic evidence of acute inflammation. The diagnosis of a parasitic infestation is generally achieved only after the pathologic examination of the resected appendices.

Patients/methods: Pathology department records were reviewed for all patients who required an operation for symptoms of acute appendicitis between 2000 and 2006. The specimens which were pathologically diagnosed to contain parasites were reevaluated for features of acute inflammation, and parasite type. The medical records were reviewed in detail to achieve a diagnostic score(Eskelinen). Radiologic imaging findings were correlated, if present.

Results: Of the 190 appendectomies performed, 6 specimens (3,15%) were found to contain parasites(4 Enterobius vermicularis, 2 Taenia subspecies). Appendectomies with Taenia showed acute inflammation, while acute inflammation was absent in the ones with Enterobius vermicularis. The Eskelinen score was higher than the threshold in two cases with an acute inflammation, and in two without. Ultrasound scans, and a computed tomography scan were performed in 5 patients. In 3 of 4 bland appendices, results favored acute appendicitis.

Conclusion: The diagnosis of gastrointestinal parasites is not only made by examining the stool but the diagnosis can be made by histology from surgical specimens. Timely diagnosis and appropriate therapy might prevent probable future complications that may necessitate surgical procedures, at least in some of the patients. The clinical management of these infections is different from that for classical appendicitis.

Figure 1

the fragment of helminthe was seen in the lumina as an elongated and flattened segment with eggs(original magnification × 40).

Figure 2

one cross, and one trans section of E. vermicularis with characteristic hooks at both sides(original magnification × 40).