Nematodes

Front 1

What are the three categories of nematodes?

Back 1

1) intestinal 2) extraintestinal 3) tissue

Front 2

What is an example of a tissue nematode?

Back 2

Trichinella spiralis

Front 3

What are 4 examples of intestinal nematodes?

Back 3

1) Ascaris lumbricoides 2) Enterobius vermicularis 3) Strongyloides sterocoralis 4) Hookworm

Front 4

What is the largest roundworm that parasitizes the human intestine?

Back 4

Ascaris lumbricoides

Front 5

What is the most common helminthic infection worldwide?

Back 5

Ascaris lumbricoides

Front 6

What is Loeffler's sydrome?

Back 6

A pneumonitis with a marked eosinophilia caused by a worm infection

Front 7

Describe the lifecycle of ascaris

Back 7

The eggs are ingested and hatch in the intestines, migrate into the intestinal lymphatics and move to the lungs

Front 8

What are symptoms of ascaris infection?

Back 8

Abdominal pain and intestinal obstruction; also pulmonary symptoms of cough, dyspnea, hemoptysis and Loeffler's syndrome when the lung phase of larval migration occurs

Front 9

What is the most common clinical manifestation of enterobius vermicularis?

Back 9

perianal pruritus, especially at night, and abdominal pain

Front 10

Describe the lifecycle of enterobius vermicularis

Back 10

The eggs are ingested from contaminated fingers and make their way to the cecum; the adults live in the cecum and migrate to the anus at night and lay eggs, with self-inoculation following due to prutitus

Front 11

Describe the test used to demonstrate the eggs of enterobius vermicularis

Back 11

The "scotch tape" test is used which involves using transparent tape to probe the perianal region and then looking at the tape under a microscope for eggs

Front 12

What phase of the life cycle of strongyloides sterocoralis is infective and which is diagnostic?

Back 12

The infective stage is the filariform larval stage and the rhabditiform stage is diagnostic

Front 13

How does strongyloides get into the body?

Back 13

It penetrates the skin

Front 14

Describe how strongyloides reaches the intestine

Back 14

The filariform larvae invades the skin and gets into the bloodstream, spreading to the lungs where it infects the alveolar spaces. It is carried to the trachea and swallowed into the stomach and passes into the intestine

Front 15

Describe the eosinophilia in strongyloides infections and in what patients do they disseminate?

Back 15

Eosinophilia is present during the acute and chronic stages but is absent in disseminated infections (which occur in immunocompromised patients)

Front 16

What is clinical manifestation is often seen with hookworm infection and why does it occur?

Back 16

Iron deficiency anemia often occurs because the worm attaches to the intestine leading to bleeding

Front 17

How does a hookworm infestation occur?

Back 17

The filariform larvae enter the skin and migrate to the intestine

Front 18

How does the trichinellosis infection occur?

Back 18

The ingestion of undercooked or raw beef or pork

Front 19

Where are the larvae in a trichinella infection?

Back 19

The larvae are found in the muscle

Front 20

What are common symptoms of trichinellosis?

Back 20

periorbital and facial edema, conjuctivitis, myalgias and weakness, blood eosinophilia

Front 21

What is usually found in the muscle of patients with trichinellosis?

Back 21

Larval encystment

Front 22

What is the preferred diagnostic test used to confirm trichinellosis?

Back 22

Muscle biopsy