Miscellaneous Intestinal Nematodes

Macracanthorhynchus hirudinaceus. Egg in fecal smear (unstained, high power). This acanthocephalan egg is large (80-100 um long by 50 um wide), ovoid, and, has a thick, dark brown, textured, shell. It contains a larva (acanthor) that possesses rostellar hooks. People become infected by ingesting an infected intermediate host, typically a beetle. The parasite, normally found in pigs and other animals, can produce serious complications associated with the gastrointestinal tract in humans.