Protozoans Flashcards
entamoeba:
1. drug of choice
2. disease
3. diagnostic technique for fresh and frozen stool
4. diagnostic technique that’s quick and easy
- metronidazole or diloxanide furoate (for asymptomatic cyst passer)
- amebiasis
- enzyme immunoassay
- rapid immunochromatographic assay
Giardia:
1. drug of choice
2. disease
3. gold standard diagnostic technique
4. diagnostic technique does not rely on microscopy and used for screening large numbers of specimen
- metronidazole
- Giardiasis
- Direct Fluorescent Antibody (DFA) assay
- Enzyme Immunoassay (EIA)
Plasmodium:
1. drug of choice give 1
2. disease
3. gold standard diagnostic technique
4. what 3 stains are used in the gold standard, which among is preferred?
- Prophylactic, Blood Schizonticidal, gametocytocidal, hypnozoitocidal, sporonticidal
- Malaria
- microscopy
- Giemsa, Wright, or Wright-Giemsa stain; Giemsa = preferred for detection of certain morphologic features
what smear is used to detect parasites? and what is for species-level identification
detection = thick smear
species-level identification = thin smear
Sarcocystis:
1. drug of choice then explain the 2
2. disease
3. what are the 5 diagnostic techniques
4. what is observed in intestinal and muscular sarcocystosis?
- Albendazole = muscular sarcocystosis, corticosteroids = symptomatic muscular sarcocystosis,
- sarcocystosis
- wet mount
wet mount in UV microscopy
negative staining according to Heine (use: carbolfuchsin stain)
PCR = to identify species
Hematoxylin and eosin stain → Periodic Acid schiff or PAS confirmatory - intestinal = oocyst and sporocyst
muscle = sporocyst
true or false: in sarcocystosis both sporulated oocyst and individual sporocyst can be found in feces? Which of these will autofluoresce in UV?
true
whats the life cycle of sarcocysts? 5 steps
Sporozoites → schizonts → merozoites (penetrate muscle cell) → cyst with bradyzoites → sporocyst / thin walled oocyst in feces
Trypanosoma:
1. drug of choice for 1st stage (for brucei and Gambian), CNS, and Hemolymphatic stage
2. disease
3. what are the 4 diagnostic techniques
- 1st brucei spp. = intravenous suramin sodium
1st gambian form = intravenous pentamidine
cns = intravenous melarsoprol
hemolymphatic = nitrofurazone (if melarsoprol fails)
eflornithine = for gambiense only - trypanosomiasis / african sleeping sickness
- thin smear, antibody detection (card agglutination, dipstick method) , molecular detection
diseases caused by
t.brucei gambiense
t.b. rhodesiense
t.b. brucei
t. cruzi
gambiense = chronic african trypanosomiasis (west african sleeping sickness)
rhodiense = acute african trypanosomiasis (east african sleeping sickness)
brucei = nagana
cruzi = chagas (vector - triatoma spp or bed bug
what protozoans are inside RBC (2) , and outside RBC or extra erythrocellular
inside = plasmodium and babesia
outside = trypanosoma
vector of trypanosoma
tsetse fly (genus Glossina)
trypanosomiasis mammalian and tsetsefly stage
mammalian =
tsetse fly bites = inject (1) metacyclic trypomastigote –> (2) bloodstream trypomastigote –> multiply in body fluids thru binary fission = circulate
another tsetse fly bites
tsetse=
taken (1) bloodstream trypomastigote = (2) procyclic trypomastigote = binary fission = (3) epimastigote = multiply in salivary gland = (4) metacyclic trypomastigote
reservoir for tb rhodiense
cattle
trypanosoma what are the vectors:
t. suis
t. evansi (7)
t equinum
suis = pig
evansi = horse, pig,
camel,
carabao, cattle,
cat , dog
equinum = equines or horse
Naegleria:
1. drug of choice then explain the 2
2. disease
3. what are the 3 diagnostic techniques and 5 stains
- amphotericin B + Clotrimazole
- Primary Amebic Meningoencephalitis
- (1) direct visualization (CSF smears: H&E, PAS, trichrome, giemsa, wright-giemsa)
direct visualization (tissue) –> trophozoite
(2) immunohistochemical staining (indirect immunofluorescent or IIF , and immune alkaline phosphatase staining–> trophozoite
(3) PCR
symptoms of PAM are indistinguishable from what disease
bacterial meningitis
naeleria spp. how it enters human body and its life cycle
trophozoite replicate by promitosis –> temporary non-feeeding flagellated forms –> trophozoite –> nose or sinus –> brain (via olfactorny nerves) –> PAM
3 stages of naegleria fowlerii, and 2 forms of trophozoite
cyst, trophozoite (ameboid, ameboflagellate), flagellated
true or false: naegleria cyst can be found in brain tissue
false:
trophozoite = in CSF and tissue
flagellated = CSF
cyst = not in brain
Leishmania :
1. drug of choice then explain the 3 and what type of leishmaniasis its for
2. disease
3. what are the 4 diagnostic techniques and 2 stains
4. among diagnostic which is conventional diagnostic approach, which is sensitive and rapid
- sodium stibogluconate & n-methyl-glucamine = for AIDS patient
amphotericin b = if stibogluconate fails
pentamidine = cutaneous and visceral = partient will have high drug resistance - Leishmaniasis
- microscopy (giemsa and H&E stain), isoenzyme analysis , serology (for antibody detection) , molecular diagnosis
- conventional = isoenzyme analysis (uses biphasic medium = blood agar + defribinated (no fibrin = no blood clot) rabbit blood –> identification using electrophoresis
sensitive and rapid = molecular diagnostic (PCR)
Leishmania life cycle
sand fly injects promastigotes –> macrophage phagocytize promastigote –> amastigote –> infect phagocytic cells
in sandfly:
amastigote –> promstigote in gut –> migrate to sand fly proboscis
2 types of leishmaniasis and their symptoms:
- cutaneous :
- one or more cutaneous lesions on areas where sandflies have fed.
- Have one or more sores on their skin. The sores can change in size and appearance over time.
- sores = like a volcano, with a raised edge and central crater. - visceral
- fever, weight loss, and an enlarged spleen and liver (usually the spleen is bigger than the liver).
- Some patients have swollen glands.
- Certain blood tests are abnormal: low RBC, WBC, and platelets
leishmaniasis:
1. infective stage and diagnostic and what they look like, where they’re found
2. transmission
3. definitive, intermediate host, vector
- infective = promastigote in sandflies = with flagella that arise from kinetoplast
diagnostic = amastigote found in macrophage = no tail, large nucleus, kinetoplast, short axoneme - infected sand fly bite, blood transfusion, etc.
- Dh = humans
IH = sand flies
vector = female phlebotomine sandflies
or sand fly = Phlebotomus papatasi
all types of lesihmaniasis and what body part it affects:
- cutaneous = most comon = volcano like crater
- diffuse cutaneous = facial area, initial diagnosis for lepromatous leprosy
- mucocutaneous = in mucus membrane of nasal and oral cavities
- visceral = spread of parasite in bone marrow, spleen, liver
differentiate old world and new world leishmaniasis
- old = asia, middle east, africa, india,
vector = phlebotomus sand fly - new = america, central or south america
vector = lutzomyia sand fly
what can invade and multiply in macrophages (3)
Leishmania spp., Toxoplasma gondii, and
Trypanosoma cruzi,
primary reservoir of leishmania in urban and rural
urban = dogs and rodents
rural = rodents
how to prevent leishmanisis
use insect repellent with DEETS and permethrin
use fine mesh bed and screens
