Ciliates and Flagellates

Only ciliate that needs to be memorized for this test is ___ ___.

Balantidium coli

Balantidium coli is transmitted by ingestion of an infective ___ through the ___ route.

Found mainly in ___ and ___ regions, especially in ___-farming areas.

cyst; fecal-oral; tropical; subtropical; pig

The natural host of Balantidium coli is mainly ___. The accidental hosts are ___.

pigs; humans

Both the cyst and trophozoite of Balantidium coli contain ___ nuclei.

• macronucleus - ___ bean shaped

• micronucleus - small, round and lives within the curvature of the ___

2; kidney; macronucleus

The micronucleus of Balantidium coli is ___ visible on stained slides.

rarely

The trophozoite of Balantidium coli has a slightly ___ anterior end containing a cilia-lined ___. It’s cytoplasm contains ___ vacuoles.

Motility is achieved via ___, gliding movement.

pointed; cytosome; food; cilia

The cyst of Balantidium coli is not very ___ visually, would have to match context clues such as ___ exposure, ciliated troph to presumptively ID it.

unique; pig

Balantidium coli primarily lives in the ___ intestine and may cause ___ lesions.

large; ulcerative

Balantidium coli infection may be ___ or cause self-limiting diarrhea with nausea, vomiting, and abdominal tenderness.

More severe B. coli infection is more likely in ___ patients and may cause abdominal pain, dysentery, persistent diarrhea, weight loss, and nausea/vomiting.

asymptomatic; immunocompromised

Untreated B. coli infection can lead to bowel ___ (hole in the wall of the gastrointestinal (GI) tract - allows stool to leak out into abdominal cavity, risk of ___ bacterial infection).

perforation; secondary

What is the name of this organism?

Balantidium coli

The main ___ flagellates to know are Giardia duodenalis, Dientamoeba fragilis, and Trichomonas vaginalis.

pathogenic

Giardia duodenalis was formerly called Giardia ___ and lives in the ___ (first part of small intestine).

lamblia; duodenum

Trichomonas vaginalis is a ___ flagellate rather than an intestinal flagellate.

urogenital

The main ___ flagellates are Chilomastix mesnili and Trichomonas hominis.

nonpathogenic

___ flagellates have 2 life-cycle stages: cyst and troph.

Name the exceptions that LACK a cyst stage:

• ___ ___

• Trichomonas ___

• Trichomonas ___

most; Dientamoeba fragilis; vaginalis; hominis

In flagellates that lack a cyst stage, the infective form is the ___.

trophozoite

Giardia duodenalis is a ___ that is ___ (non or patho).

Infective form: ___ via ___ route.

Body site where infection occurs: ___ (duodenum)

Cysts:

• up to ___ nuclei

• appearance on trichrome often ___ due to ___ flagella and other internal structures

flagellate; pathogenic; cyst; fecal-oral

intestines; 4; cluttered; retracted

Giardia duodenalis Trophs:

• pear, teardrop shaped, bilaterally symmetric

• “___ ___” appearance due to bi___ (2 oval nuclei)

• “falling ___” motility

• ___ pairs of flagella

• ventral ___ disk

old man; nucleate; leaf; 4; sucking

Dientamoeba fragilis is a ___ that is ___ (non or patho).

Infective form: ___ (transmission unclear)

Body site where infection occurs: ___

Cysts: LACKS cyst form!

Trophs:

• tiny

• most are __nucleate (“Di”-entamoeba)

• karyosome consists of 4 to 8 discrete ___ (nucleus is fragmented)

• outline indistinct and ___ into background (cuz its tiny)

flagellate; pathogenic; trophozoite

intestines; bi; granules; blends

Trichomonas vaginalis is a ___ that is ___ (non or patho).

Infective form: ___ passed person-to-person as a ___

Body site where infection occurs: ___ tract

Cysts: LACKS cyst form!

Trophs:

• ___ anterior (front) flagella

• Undulating membrane - extends ___ the length of body

• ___ motility

flagellate; pathogenic; trophozoite; STI

urogenital; 4; half; jerky

Chilomastix mesnili is a ___ that is ___ (non or patho).

Infective form: ___ via ___ route

Cysts:

• ___ shaped w/ anterior ___

• Small central ___ in nucleus that is ___ by fibrils that curl around the cytosome (shepherd’s ___ appearance)

• On Trichrome: nucleus, cytosome, and curved fibrils are visible

Trophs:

• cytosome and nucleus are prominent in ___ of organism

flagellate; nonpathogenic; cyst; fecal-oral

lemon; knob; karyosome; surrounded; crook; anterior

(Penta)trichomonas hominis is a ___ that is ___ (non or patho).

Infective form: ___ associated with ___ contamination

Body site where infection occurs: nonpathogenic, but may colonize the ___ intestine

Cysts: LACKS cyst form!

Trophs:

• ___ anterior flagella

• Undulating membrane - extends the ___ of organism

flagellate; nonpathogenic; trophozoite; fecal

large; 4; length

Giardia (lamblia) duodenalis process of infection

1. begins with ingestion of infective ___ by the ___ route.

2. host’s stomach acid initiates ___, and cyst then moves to the ___ (first part of small intestine).

3. senses the pH ___ from stomach to intestine

4. in response, attaches to ___ of small intestine in duodenum via ventral ___ disk

5. carbs and bile in area stimulate ___ growth

cysts; fecal-oral

excystation; duodenum

shift

lining; sucking

trophozoite

Giardia (lamblia) duodenalis

Risk factors:

• fecal-oral, drinking ___ water where ___ live (one of the major animal reservoirs)

• travel to ___ areas (especially those w/ poor ___)

• children in ___ centers (person-to-person spread)

untreated; beavers; endemic; sanitation; daycare

Giardia (lamblia) duodenalis cyst viability:

• very ___! can survive several months in cold water.

• somewhat resistant to ___ and ___

• susceptible to desiccation (drying) and ___ (~50C)

resistant; bleach; iodine; heat

Giardia (lamblia) duodenalis is the ___ commonly reported intestinal protozoan infection in US.

• It requires a LOW infectious dose of ___ cysts (takes very little contamination to lead to an outbreak)

The causative agent of ____ and “___’s” diarrhea (aka “backpacker’s diarrhea” or “beaver fever”).

most; 10; gastroenteritis; traveler

Acute infection with Giardia (lamblia) duodenalis is mostly self-___.

Incubation period: 12-___ days

Symptoms:

• can cause ___ (general feeling of discomfort), cramps, nausea, and abdominal tenderness

• ___, foul-smelling, non-blood diarrhea (1-4 weeks)

limiting; 14; malaise; explosive

Chronic infection with Giardia (lamblia) duodenalis causes persistent ___-like syndrome (fats and vitamin B12).

Can cause upwards ___% of weight loss, fatigue, anorexia, steatorrhea (oily-lipid rich stool), and large amounts of gas (since carbs and lipids are not properly absorbed – bacteria feast and break them down, producing gas).

malabsorption; 20

Giardia (lamblia) duodenalis organisms vary in ___ throughout the stool.

• Concentration methods and trichrome may be ___ for detection!

Stool ___ may be more reliable, including:

• ___ immunoassays using monoclonal Ab

• ___ tests (rapid ~15 min)

• DFA to detect cysts in stool

concentration; unreliable

immunoassays; enzyme; immunochromatographic

Duodenal ___ may be used for detection of Giardia (lamblia) duodenalis when persistent symptoms or refractory/resistant treatment are encountered, but organism is not ID’d in the ___.

aspirates; stool

Trichomonas vaginalis process of infection

1. ___ form is passed person-to-person via intercourse

2. establishes infection in the ___ tract. (No ___ stage)

trophozoite; urogenital; cyst

Trichomonas vaginalis

Risk factors: STI; sexual exposure to an infected person

• mostly ___ carriers (especially in men) is one of the reasons why transmission keeps happening

Incubation period: 5-___ day incubation period

asymptomatic; 28

Trichomonas vaginalis common symptoms:

In women:

• more ___ compared to men (___ symptomatic, 2/3 asymptomatic)

• vaginal itching

• frothy, creamy, mucopurulent discharge

• ___ (painful urination)

• Chronic infection:

  • Mild symptoms; major source of transmission (may lead to Pelvic Inflammatory disease)

symptomatic; 1/3; dysuria

Trichomonas vaginalis common symptoms:

In men:

• more commonly ___ carriers

• nongonococcal ___ (inflammation of urethra -> painful urination)

• milky discharge (4 weeks)

asymptomatic; urethritis

The most practical and rapid method for Trichomonas vaginalis identification is ___ ___ prep.

• ID during urinalysis

• Not as sensitive as DFA (Direct Fluorescent Assay)

Other methods of identification of Trichomonas vaginalis includes:

• Fluorescent staining of exudates (sensitivity 30-70%)

• Commercial system using plastic pouch

• PCR

• EIA using monoclonal abs

• Immunochromatographic tests

wet mount

Trichomonas vaginalis infection…

• may occur along with other ___, such as gonorrhea.

• may possibly be transmitted from a pregnant mother to her ___.

• is associated with cervical neoplasia and pelvic ___ disease.

  • PID can occur if the organism ascends into the uterus, fallopian tubes, and ovaries

• is associated with an increased risk of ___ due to inflammatory damage of mucosal membranes

STIs; newborn; inflammatory; HIV

What cyst?

Hint: Up to 4 nuclei; appearance on trichrome cluttered due to retracted flagella and other internal structures

Giardia duodenalis

What troph?

Hint: “Old man” appearance (binucleated); Teardrop shaped; 4 pairs of flagella; ventral sucking disk; “falling leaf” motility

Giardia duodenalis

What troph?

Hint: No cyst form; Tiny; most binucleated; Karyosome consists of 4 to 8 discrete granules (nucleus is fragmented – unique!)

Dientamoeba fragilis

What troph?

Hint: no cyst form; 4 anterior flagella; undulating membrane extends HALF the length of body; jerky motility

Trichomonas vaginalis

What cyst?

Hint: Lemon shaped w/ anterior knob; karyosome surrounded by fibrils that curl around the cytosome (Shepherd’s crook appearance)

Chilomastix mesnili

What troph?

Hint: Cytosome and nucleus are prominent in anterior of organism

Chilomastix mesnili

What troph?

Hint: no cyst form; 4 anterior flagella; undulating membrane extends the LENGTH of organism

Trichomonas hominis