Gastric ascariasis.

Despite the ubiquity and varied manifestations of Ascaris lumbricoides infestation in man, gastric ascariasis is rare. Herein, three patients are described all of whom presented with features of chronic intermittent gastric outlet obstruction caused by roundworms inhabiting the stomach. The ascarides were demonstrated in the stomach by radiology in two patients and by endoscopic examination in one. The possible explanations for the rarity of "gastric ascariasis" include the "housekeeping" peristaltic activity and the acid milieu of the stomach.