The eggs of E. vermicularis which can be seen in the picture are roughly 25 x 60 um in size. The organism has a thin shell and one of the sides is compressed. The eggs and shell of organism have taken up the pink dye which makes them recognizable.
The presence of E. vermicularis in the appendix can give the symptoms of acute appendicitis (Wiebe, 1991, p.g. 336). The appendix is a vestigial organ present in the human body. The inflammation of this organ leads to appendicitis. Acute appendicitis is one of most common diseases that lead to inflammation of the gastrointestinal tract. Acute appendicitis is caused due to the obstruction of the lumen, diminished blood supply, pinworm infections caused by Enterobius vermicularis, bacterial infections or due to ischemic damage to mucosal lining of organ (Becker and Hofler, 2002, pg.777). The best described pathogenesis of appendicitis is an obstruction in the appendiceal lumen. The obstruction can be due to lodging of foreign body, lymphoid hyperplasia, fecolith or tumours. The pathogenesis of appendicitis can be understood by the course that the disease takes. In the primary stage, there is obstruction of the lumen which causes accumulation of fluid leading to elevation of intraluminal pressure and lastly resulting in distension of lumina. Suppurative appendicitis occurs due to increased intraluminal pressure which increases the capillary perfusion leading to venous obstruction and hence causing arterial compromise. These crucial events lead to ischemia of the mucosal surface and allow bacterial infestation. As the disease progresses, it causes mural infection which is characterized by oedematous thickening of the appendicular walls. When observed grossly the appendix appears hyperaemic and enlarged. If this progressive condition is not managed surgically it may lead to perforation and gangrene. Gangrenous appendicitis may present as friable serosa with green or black discoloration. If