(In Progress - Do not Use) General Concepts in Parasitology Laboratory Methods

Question 1

Trophozoite (Troph)

Answer 1

The motle and reproductive form of protozoa.

Question 2

How many stool specimens should be collected for optimal detection of intestinal parasites?

Question 3

Protozoa

Answer 3

Term used to collectively refer to unicelular parasites.

Question 4

Helminths

Answer 4

Term used to collectively refer to the multicellular parasites.

Question 5

What type of collection container is used for stool specimens?

Answer 5

Clean, dry, sealed, and waterproof container ( ex. plastic container with a lid)

Question 6

Stool specimens collected for parasites, should never be collected from…

Answer 6

Bedpans or toliet bowls. Urine can destory trohpozoites and toliet water could introduce free-living protozoa.

Question 7

Stool specimens for parasites should be collected before…

Answer 7

Barium enema, certain procedures using dyes, or the start of antimicrobial therapy. Barium can obscure parasites. If a purged specimen is to be collected, it is recommended that a saline or phosphosoda purgative be used. Mineral based purgatives can interfere with the identification of parasites.

Question 8

What is the ratio of preservative to feces?

Answer 8

Three parts preservative to one part feces.

Question 9

What commercially available two-vial preservative system is commonly used for parasites?

Answer 9

Polyvinyl alcohol (PVA) and 10% formalin.

Question 10

What toxic compound is found in Polyvinyl alcohol?

Answer 10

Mercuric chloride