Intestinal nematodes (Part 1)

Question 1

List the common name for the Ascaris.

Answer 1

None

Question 2

Diagnostic form of Ascaris.

Answer 2

Eggs/ eggs ingested from oil, food, water

Question 3

Describe the microscopically appearance of Ascaris.

Answer 3

• Oval eggs, often stain brown in stool
• Infertile eggs are elongated, bizarre shaped (no male present)
• Mammilated coat (decorticated= lost coat)

Question 4

List the common name for the Ancylostoma duodenale.

Answer 4

Hookworm. (old world)

Question 5

List the common name for the Necator americanus.

Answer 5

Hookworm. (new World)

Question 6

Diagnostic form of Hookworm and describe the microscopically appearance.

Answer 6

Eggs in stool- oval, colorless, thin-shelled
Filariform larvae- pointed tail
Rhabditiform larvae- bulb in some area and longer buccal cavity.
Adult

Question 7

Differentiate Ancylostoma and Necator in diganosis of hookworm adults.

Answer 7

Ancylostoma has two pairs cutting teeth

Necator has cutting plates

Question 8

List the common name for the Strongyloides stercoralis

Answer 8

Threadworm

Question 9

Diagnostic form of Strongyloides stercoralis.

Answer 9

Rhabditiform Larvae; eggs rarely seen in stool (if eggs are ever seen that resembles hookworm)

Question 10

Microscopic appearance of Larvae see in Stronglyoides stercoralis.

Answer 10

Rhabditiform larvae seen in stool- short buccal cavity and large genital primordium (“short & sexy)
Filariform larvae-notched tail

Question 11

List the common name for Enterobius vermicularis.

Answer 11

Pinworm (sharply pointed tail of female)

Question 12

Diagnostic form of Enterobius vermicularis.

Answer 12

No fecal specimen (eggs not usually seen in feces).
cellophane tape preparation or paddle.
Lay eggs outside anus at night

Question 13

Describe the microscopic appearance of Enterobius vermicularis: Adult female and Eggs.

Answer 13

Adult female= pointed tail (male tail is curved, alae (3 lips)
Eggs oval, slightly flattened, with thin, smooth, colorless shell. Usually internal larvae can be see.

Question 14

List the common name for Trichuris trichiura.

Answer 14

Whipworm

Question 15

The diagnostic form of Trichuris trichiura.

Answer 15

Eggs passed in stool (occasionally adult)

Question 16

Microscopic appearance of eggs in Trichuris trichiura.

Answer 16

Barrel-shaped eggs, with polar plugs at each end, unembryonated.

Question 17

List the common name for nematodes.

Answer 17

Roundworms.