Angiostrongylosis

Abdominal Angiostrongylosis is an accidental parasitosis of man by Angiostrongylus costaricensis – a species usually found in rats, acquired by eating third stage larvae from slugs or their mucus left on unwashed vegetables. Most of the cases have been found in the Americas, and only a few in Africa. The larvae enter the intestinal wall and migrate to the arteries of the ileocolic region where they become adult (Pathology, Fig. 23B). The eggs are deposited in the vessel; and are propelled into the intestinal mucosa where they give rise to an intense granulomatous inflammation with eosinophils and fibrosis. Most of the eggs degenerate; although larvae are occasionally seen in the tissues, they have not been found in the stool where they are shed by the natural host (Pathology, Fig. 29A–D). Many of the arterioles containing adults become thrombosed after the worms die. The lesions may simulate appendicitis or give rise to large inflammatory ileocolic masses which can cause intestinal...