PROTOZOANS (Flagellates)

Question 1

Trophozoite morphology:
- Pear-shaped
- Motility: “falling leaf”
- Nuclei 2” “old man with glasses”, “Monket face”
- Flagella: 4 lateral pairs (2 ventral, 2 dorsal)
- Sucking disc
- Variant specific surface proteins

Cyst morphology:
Cytoplasm often retracted from cyst wall (especially in preserved in formalin)
“Halo effect”

Answer 1

Giardia lamblia/ intestinalis/ duodenale

Question 2

Diseases caused by. G. lamblia/ intestinalis/ duodenale:

Answer 2

• Gay bowel syndrome
• Leningrad’s curse (traveler’s diarrhea)
• Backpacker’s diarrhea
• Beaver fever

Question 3

Transmission of G. lamblia/ intestinalis/ duodenale:

Answer 3

• Fecal-oral
• Sexual

Question 4

Diagnostic test(s) for G. lamblia/ intestinalis/ duodenale:

Answer 4

• Direct Fluorescent Ab - Most sensitive & specific
• Enterotest (String test)

Question 5

Trophozoite morphology:
- prominent cystostome
- Shepherd’s crook
- Spiral groove
- Rotary motility

Cyst morphology:
- Lemon-shaped with anterior, hyaline knob (nipple-like)

Answer 5

Chilomastix mesnili

Question 6

Disease caused by Chilomastix mesnili:

Answer 6

Commensal - considered as non-pathogenic

Question 7

Trophozoite morphology:
- Amoeboid, “stellate” appearance
- Nuclei: 2, with 4-8 karyosome each
- Hakansson phenomenon: explosive disintegration in water
- Formerly classified as amoeba

NO CYST STAGE

Answer 7

Dientamoeba fragilis

Question 8

Disease caused by D. fragilis:

Answer 8

Concomitant with pinworm infections or Ascaris infection

Question 9

Diagnostic stage of Dientamoeba fragilis:

Answer 9

Binucleatte trophozoite

Question 10

In diagnosing Dientamoeba fragilis infection, consider:

Answer 10

• fresh stool/ purged stool

Question 11

Trophozoite morphology:
- Undulating membrane: extends length of the body
- Characteristic wobbly movement

NO CYST STAGE

Answer 11

Pentatrichomonas hominis

Question 12

Trophozoite morphology:
- Undulating membrane: extends 1/2 length of the body
- Rapid, JERKY MOTILITY
- Siderophil granules

NO CYST STAGE

Answer 12

Trichomonas vaginalis

Question 13

Disease caused bt T. vaginalis:

Answer 13

Strawberry cervix
Ping-pong infection

Question 14

Medium used for diagnosing T. vaginalis infection:

Answer 14

Diamond’s medium

Question 15

Developmental stages of Blood flagellates:

Answer 15

1. Amastigote
2. Promastigote
3. Epimastigote
4. Trypomastigote

Question 16

Vector of Leishmania species:

Answer 16

Sandflies (phlebotomus)

Question 17

Leishmania species that inhabits Cutaneous/Tissue juice
and causes Cutaneous leishmaniasis:

Answer 17

• L. tropica
• L. major
• L. mexicana

Question 18

Leishmania species that inhabits Mucocutaneous/Tissue juice and causes Mucocutaneous leishmaniasis:

Answer 18

• L. braziliensis

Question 19

Leishmania species that inhabits Visceral blood and causes Visceral leishmaniasis:

Answer 19

• L. donovani
• L chagasi
• l. infantum

Question 20

STAGES present in Leishmania species:

Answer 20

• Amastigote
• Promastigote

Question 21

Leishmania species
Infective stage:
Diagnostic stage:

Answer 21

Leishmania species
Infective stage: Amastigote
Diagnostic stage: Promastigote

Question 22

Culture used for Leishmania species:

Answer 22

Novy-Macneal-Nicolle medium

Question 23

(+) Montenegro skin test/ Leishmanin test:

Answer 23

(+) induration

Question 24

Tests for Visceral leishmaniasis:

Answer 24

1. Aldehyde test for Napier (formol gel test)
2. Antimony test of Chopra

Question 25

Vector of Trypanosoma brucei rhodesiense;

Answer 25

Game-attacking Glossina spps (tsetse fly)

Question 26

Vector of Trypanosoma brucei gambiense:

Answer 26

Riverine Glossina spps (tsetse fly)

Question 27

Disease caused by T. brucei rhodesiense:

Answer 27

- Acute African or East African Trypanosomiasis (more severe) - Sleeping sickness = Nagana's disease

Question 28

Disease caused by T. brucei gambiense:

Answer 28

- Chronic African or West African Trypanosomiasis -Sleeping sickness = Nagana's disease

Question 29

Stages present in T. brucei rhodesiense and gambiense:

Answer 29

- Epimastigote - Trypomastogote

Question 30

T. brucei rhodesiense & gambiense Infective stage: Diagnostic stage:

Answer 30

T. brucei rhodesiense & gambiense Infective stage: Trypomastigote Diagnostic stage: Metacyclic trypomastigote

Question 31

T. brucei rhodesiense & gambiense infective forms are passed in:

Answer 31

Saliva (salivarian)

Question 32

Important pathogenesis of T. brucei rhodesiense & gambiense 1st stage = ?

Answer 32

1st stage = Skin lesions

Question 33

Important pathogenesis of T. brucei rhodesiense & gambiense 2nd stage =

Answer 33

2nd stage = Entrance into blood and lymph, liver, spleen, bone marrow "Winterbottom's sign" (swollen lymph node

Question 34

Important pathogenesis of T. brucei rhodesiense & gambiense 3rd stage =

Answer 34

3rd stage = CNS involvement, Somnolence (excessive sleepiness), Kerandel's sign (delayed pain on compression of soft tissue)

Question 35

Vector of Trypanosoma cruzi:

Answer 35

- Reduvid bug/ cone-nosed bugs/ kissing bugs/ assassin bugs - Triatioma infestans - Panstrongylus megistus - Rhodnius prolixus

Question 36

Vector pf T. cruzi seen in the Philippines:

Answer 36

- Triatoma rubrofasciata

Question 37

Diseases caused by Trypanosoma cruzi:

Answer 37

- South American Trypanosomiasis - Chagas disease

Question 38

Stages present in Trypanosoma cruzi:

Answer 38

- Amastigote - Promastigote - Epimastigote - Trypomastigote

Question 39

Trypanosoma cruzi Infective stage: Diagnostic stage:

Answer 39

Trypanosoma cruzi Infective stage: Metacyclic trypomastigote Diagnostic stage: - Blood: Trypomastigote - Tissue: Amastigote

Question 40

Culture used in diagnosing T. cruzi infection:

Answer 40

- Chang's medium - Novy-Macneal-Nicolle medium

Question 41

Stages obtained/observed in Xenodiagnosis of T. cruzi:

Answer 41

- Epimastigote - Trypomastigote

Question 42

Important pathogenesis of T. cruzi infection:

Answer 42

Acute: Anemia Chronic: Heart is primarily affected. May also cause achalasia and megacolon Manifestations: Chagoma (swelling) ROMAÑA'S SIGN (swelling of the eyelid)

Question 43

Stercorarian trypanosoma:

Answer 43

Trypanosoma cruzi

Question 44

Salivarian trypanosma:

Answer 44

T. b. rhodesiense T. b. gambiense