Protozoans

Parasite that moves in one direction and only has one pseudopod, endoplasm that contains RBC but not bacteria or cell dendritus. Nucleus is not visible when stained and has a finely centrally located karyosome. “clean-looking”

Cyst is coffin-shaped chromatoidal bars with 4 nuclei (Quadrinucleated0

Entamoeba histolytica

Entamoeba histolytica pathogenesis:

_______________________ - acute amoebic colitism “flask-shaped” or teardrop ulcer

_______________________ - Liver with reddish brown or anchovy sauce abscess

Intestinal amoebiasis - flask / teardrop

Extraintestinal amoebiasis - anchovy

A parasite that moves in several different directions simultaneously in a sluggish motion. Sends out several pseudopods, the endoplasm contains bacteria. Stained nucleus consists of thicker nuclear membrane with layer of variously sized chromatin granules. “dirty looking”

Cyst’s chromatoidal bars are seen splinter'-like needles

Entamoeba coli

Has a small trophozoite with sluggish movement, Karyosome appears like a large dot.

Cyst is also small in diameter and is usually oval. It posseses 4 nuclei when mature (cross-eyed)

Endolimax nana

Parasite includes intracellular inclusions and motility same as E. coli. Karyosome is large, irregular and rounded with a cluster of achromatic granules.

In the cyst, it only has one nucleus when mature, its most prominent feature is the large iodine-staining glycogen vacuole

Iodamoeba butschili

Parasite exhibits pseudopodia similar to E. histolytica but does not exhibit true progressive locomotion. It has no cystic stage

Entamoeba gingivalis

Parasite that is the main cause of Primary Amoebic Meningoencephalitis. Can be infected through oral and intranasal routes while swimming in contaminated pools.

Naegleria fowleri

Parasite that causes Granulomatous Amoebic Meningoencephalitis. It causes Keratitis in persons who use daily-wear or extended wear of contact lenses or who have experienced trauma to the cornea.

Acanthamoeba

Parasite that has a halo effect on its cyst, a falling leaf / flip-flop motility and 4 pairs of flagella. 2 nuclei that looks like an old man with eyeglasses or monkey face.

Gay bowel syndrome / Leningrad’s curse, Travelers diarrhea etc.

Giardia lamblia

Parasite with a lemon-shaped anterior and a hyaline knob cyst. Stiff rotary motility or a sheperd crook’s appearance, a prominent cytosome that looks like a pear for the trophozoite

Chilomastix mesnili

Parasite with no cyst stage, Amoeboid with a stellate appearance, it is a tetrakaryosome with explosive desintegration in water. It is concomintant with pinworm infection

Dientamoeba fragilis

Parasite found in the genitalia, it is the largest of the Trichomonas with an ovoidal nucleus. It has an undulating membrane and Siderophil granules.

It causes Strawberry cervix, Ping-pong infection, and Diamond’s medium

Trichomonas Vaginalis

Morphological stages of blood flagellates (4)

Amastigote

Promastigote

Epimastigote

Trypomastigote

Also known as Cutaneous Leishmaniasis / Old world Leishmaniasis, oriental sore, tropical sore.

DS: Amastigote

IS: Promastigote

Leishmania tropica

Also known as Mucocutaneous leishmaniasis / New world leishmaniasis. Causes espundia, chiclero ulcer, uta, weeping ulcer etc.

Leishmania braziliensis

Also known as Visceral leishmaniasis that causes darkening of skin “kala-azar” dum-dum, death fever, Burdwan fever, black fever etc.

Leishmania donovani

Vector of Leishmania species

Sandfly

Parasite species where Epimastigote and Trypomasigote are the visible stages.

DS: Trypomastigote

IS: Metacyclic trypomastigote

Trypanosoma brucei

Pathogenesis of Trypanosoma brucei

1st stage: ______ lesions

2nd stage: entrance into the blood and lymph, liver, spleen, bone marrrow, also known as the _____________ sign

3rd stage: CNS involvement, causes Somnolence or ____________ sign

Skin lesions

Winterbottom’s sign

Kerandal’s sign

Trypanosoma species that causes Acute Africanosomiasis / sleeping sickness, and East African trypanosomiasis

Trypanosoma brucei rhodesiense

Parasite that causes Chronic African trypanosomiasis/sleeping sickness and West African trypanosomiasis

Trypanosoma brucei gambiense

Vector of Trypanosoma brucei

Tse-tse fly / Glossina spp.

Trypanosoma species:

Stages: APET

DS: T is found in the blood, A is in the tissue

IS: Metacyclic trypomastigote

Trypanosoma brucei

Parasite that causes South American Trypanosomiasis/Chaga’s disease. It causes Chagoma and Romana’s sign

Trypanosoma cruzi

Vector of T. cruzi

Reduviid bugs

Parasite found in hogs, it has a micronucleus and macronucleus, a ciia, and contractile vacuoles.

cyst has a 1 large macronucleus, and the trophozoite has a 1 large kidney-shaped macronucleus that has a rolling ball / thrown ball motility

Disease causes ulceration with a wide mouth and a rounded base; NO extraintestinal infection

Balantidium coli