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This appendix does show marked acute appendicitis, but inflammation centered on the eggs is not a particular feature.

Within the inflamed wall is an incidentally detected partially intact egg. Most often this finding is seen in appendices removed for acute inflammation, but usually the parasite is not the actual cause of the appendicitis.

High power illustrates some substructure to the parasite with the intestinal tract present.


Enterobius vermicularis, commonly referred to as "pinworm", is one the parasitic roundworms with a worldwide distribution. It is most commonly encountered in adolescents and children. The medical condition associated with pinworm infestation is known as enterobiasis, and infection usually is due to ingestion of pinworm eggs, through contaminated hands, food, or less commonly, water. When encountered in the appendix, there is often little inflammatory reaction.


Many patients with enterobiasis are asymptomatic, but when symptomatic, the chief symptom is itching in the anal area.


For enterobiasis, treatment with Albendazzoe or Mebendazole is effective. Because the drugs kill the adult pinworms but not the eggs, retreatment is recommended in two weeks.

Last updated: 2010-02-19
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