Exam 49: Intestinal Nematodes

Rhabditiform larvae measuring 275 mm with a long buccal capsule and a small genital primordium was identified as hookworm.Which one of the following statements explains this discrepancy?

A 4-year-old boy attended day care 3 days per week.He was irritable,and his parents noticed that he had persistent perianal itching.A sticky paddle was pressed against the perianal region and sent to the laboratory for testing.The eggs microscopically observed would most likely have which one of the following morphologic features?

The eggs of the A.lumbricoides worm are ingested and hatched in the duodenum,penetrate the intestinal wall,and migrate to the hepatic portal circulation.Its geographic distribution and infection rate are associated with:

Direct penetration of which of the following worms results in tissue damage at the site of attachment,blood loss,and an acute gastrointestinal phase demonstrated by an increased eosinophilia?

The most common and largest roundworm encountered is:

The infective larvae of the parasite S.stercoralis penetrate the skin and migrate through the circulatory system to the heart and lungs.The organism enters the bronchial tree and is then swallowed,entering the digestive tract,where the organism matures into an adult worm.This parasite is classified as which type of infection?

The larvae of the worm S.stercoralis are the most common found in human stool specimens.Depending on the fecal transit time through the intestine and the patient's condition,both rhabditiform and rare filariform may be present.The treatment of choice for uncomplicated infections is:

Löffler syndrome is associated with which roundworm infection?

A short buccal capsule,large bulb on the esophagus,and prominent genital primordium are all characteristics of which worm?

A 36-year-old man entered the emergency department with bleeding and weight loss several weeks after returning from a trip to South America.A stool sample was taken and microscopically examined.Barrel-shaped eggs with bipolar plugs were observed.The organism can be identified as: