Quick Review Cards for Medical Laboratory Science

Flagellates of the Intestinal and Urogenital

Tractscontinued

Clinical Microbiology Review 241

FLAGELLATE TROPH CYST TRANSMISSION PATHOGENIC? OTHER

Chilomastix
mesnili

Trichomonas
hominis

Easier to ID

living organism.

Rotary motion.

6–24 μm. Broad anterior, tapering

posterior. 3 flagella at anterior,

one at posterior. Spiral groove

running length of body. Promi-

nent cytostome bordered by

fibrils. Single nucleus at anterior.

Stiff rotary motility.

6–14 μm. Prominent axostyle

extending through posterior.

4 anterior flagella. Undulating

membrane entire length of body

along costa. 1 oval nucleus with

small karyosome.

6–10 μm. Round with

bulge at anterior. Single

large nucleus. Hourglass-

shaped cytostome &

prominent fibrils.

“Lemon cyst.”

None

Ingestion of cyst

Ingestion of fecally

contaminated

material

No

No

continued...