Intestinal & Tissue Coccidian + Babesia (nd onting malaria quiz) Flashcards
What do you call the group of microscoping, spore-forming, unicellular obligate intracellular protozoans?
Coccidians
The intestinal sporozoa of man includes what species?
- Isosospora belli (Cystoisospora belli)
- Cryptosporidium parvum
- Cyclospora cayetanensis
+ 2 species of Sarcocystis
The sporozoans are part of Phylum what?
Phylum Apicomplexa
____ is a parasite of epithelial cells of the intestine, in which it may undergo repeated asexual development, with consequent destruction of the surface layer of considerable portions of the intestine.
Isospora
Isospora parasites’ sexual stages occur and culminate in ____ and passed in ____.
oocysts; feces
C. belli cycle
The immature oocysts released from the intestinal wall and passed in feces undergo development in stool. With that, the spherical mass of undivided protoplasm contained inside the immature oocyst divides to form how many sporoblasts?
2 sporoblasts
C. belli cycle
The two sporoblasts develop heavy cyst walls and become known as what?
sporocysts
C. belli cycle
Within each sporocyst, how many curved, sausage-shaped sporozoites develop?
4
C. belli cycle
The whole process of maturation from the protoplasm-containing immature oocyst to containing fully developed sporocysts and sporozoites takes ____ to ____ days
4 to 5 days
C. belli cycle
After mature oocysts w/ sporozoites are ingested by human hosts, sporocysts will excyst and undergo schizogony where?
small intestine
they will undergo schizogony in the epithelial cells
C. belli cycle
____ results in the development of unsporulated/immature oocysts that are excreted in the stool.
Fertilization
C. belli cycle
Sporulation usually occurs within how many hours after passage w/ stool?
48 hours
Infective stage of C. belli?
Mature (Sporulated) oocysts
w/ 2 sporocysts & 4 sporozoite in each sporocyst
Diagnostic stage of Cytoisospora belli?
Unsporulated oocyst
MOT of C. belli
Ingestion of contaminated food and water
= fecal-oral possible too
C. belli may be seen in stool through DFS and Conc. techniques. In direct microscopic examination, the smears must be stained w/ what?
Iodine
iodine-stained smear
this is ‘cause oocysts are transparent and difficult to recognize if smears are unstained
C. belli may be seen in stool through DFS and Conc. techniques. What concentration technique/s may be used?
- ZnSO4
- Sheather’s sugar flotation
What is the most sensitive and accurate method for detecting C. belli oocysts in feces?
Sheather’s sugar flotation technique
What test may be used to recover C. belli oocysts in the small intestine?
Entero-test
What stain/s may u use to detect C. belli in stool?
- Kinyoun method
- Modified acid-fast technique
& iodine too
Acid-fast stains (kinyoun is acid-fast too) in general will produce oocysts that are red in color (sporoblasts ang red)
Blood examination during Cytoisospora belli infections will reveal what blood condition?
eosinophilia
Peripheral Eosinophilia
This accounts why Charcot-Leyden crystals are present in stool too
Drug of choice for C. belli infections
Trimethoprim-sulfamethoxazole
What are the two species wherein human sarcocystosis is attributed to?
- Sarcocystis suihominis
- Sarcocystis hominis or Sarcocystis bovihominis
Humans serve as the ____ host for both species of Sarcocystis but occasionally, humans can act as intermediate hosts
definitive
Sarcocystis life cycle
Thin-walled oocyst or individual sporocyst is digested by intermediate host and ruptures to release what?
sporozoites
Sarcocystis life cycle
The endothelial-cell-invasion of the blood vessels produces what generation schizont?
First generation schizont
w/ merozoites
Sarcocystis life cycle
The capillary invasion of the blood vessels produces what generation schizont?
Second generation
w/ merozoites
Sarcocystis life cycle
Once secondary merozoites are released, hey invade muscle cells and transform into what containing what?
Sarcocyst containing Bradyzoites
Sarcocystis life cycle
What stage can be found in an undercooked meat and are released in the small intestine once the cyst ruptures?
Sarcocyst w/ Bradyzoites
What is the infective stage of Sarcocystis to the intermediate host?
Thin walled oocyst or sporocysts
What is the infective stage of Sarcocystis to the definitive host (humans)?
Bradyzoites in a Sarcocyst
Diagnostic stage of Sarcocystis?
Thin-walled sporulated oocyst or sporocyst
MOT of Sarcocystis
ingestion of undercooked meat w/ bradyzoites
Diagnostic methods for Sarcocystis
- DFS (but indistinguishable from each other)
- Muscle biopsy
The species of Cryptosporidium that infects humans and most mammals is what?
C. parvum
What is the infective stage of C. parvum?
Sporulated thick-walled oocyst
What is the diagnostic stage of C. parvum?
Sporulated thick-walled oocyst
MOT of Cryptosporidium parvum
ingestion of contaminated food and water
Unlike the usual oocysts of Apicomplexa, anong wala sa Cryptosporidium parvum?
no sporocysts
the thick-walled oocyst has four sporozoites na agad
Cryptosporidium parvum life cycle
Once the thick-walled oocyst reaches the small intestine, it will excyst. Next, it will undergo schizogony or merogony in what specific part of the intestinal tract?
eto yung absorptive surface w/ microvilli; place where absorption takes place
brush border
Cryptosporidium parvum life cycle
The asexual cycle (schizogony or merogony) will form what?
Meronts
w/ merozoites (like schizont w/ meroz pero now merogony ksi so meronts)
Type I - after ng brush border merogony
Type II - from type I meront to undergo gametogony
Cryptosporidium parvum life cycle
The type II merozoites will undergo sexual multiplication (gametogony) to become an undifferentiated what?
Gamont
Cryptosporidium parvum life cycle
A fertilized zygote is formed after the union of micro and macrogamonts. Then two types of oocysts are formed, what are they?
- Thick-walled oocysts
- Thin-walled oocysts
In the life cycle of Cryptosporidium parvum, what type of oocyst remain in the intestine and cause autoinfection?
Thin-walled oocyst
In the life cycle ofCryptosporidium parvum, what type of oocyst are excreted from the host into the environment?
Thick-walled oocyst
The diagnosis of Cryptosporidium parvum may be done through identifying organisms in intestinal biopsy such as?
- meronts w/ merozoites
- gamonts w/ micro & macrogamonts
= gamonts are undifferentiated pa so iba siya w/ d micro nd macro
Like Cytoisospora belli, what concentration method may be used to demonstrate Cryptosporidium parvum’s diagnostic stage?
- ZnSO4 flotation
- Sheather’s sugar flotation
+ FEACT sedimentation followed by layering and flotation over hypertonic NaClto separate oocysts from stool debris
Cryptosporidiosis clinically resembles what?
Giardiasis
Treatment for Cryptosporidiosis
Nitazoxanide
This coccidian is once known as large Cryptosporidium, coccidian-like body, cyanobacterium-like body, blue-green alga is now named what?
Cyclospora cayetanensis
Infective stage of Cyclospora cayetanensis?
Mature (Sporulated) oocyst
Diagnostic stage of Cyclospora cayetanensis?
Unsporulated oocyst
MOT of Cyclospora cayetanensis?
ingestion of contaminated food and water
The unsporulated oocysts of Cyclospora cayetanensis is passed in stool wherein sporulation occurs within how many weeks?
1-2 weeks
The mature (sporulated) oocyst of Cyclospora cayetanensis has how many sporocysts and sporozoites?
2 sporocysts w/ 2 sporozoites each sporocyst
What intestinal coccidian has the same life cycle as Cryptosporidium parvum?
only change is the presence of sporocysts then inside them r sporozoites
Cyclospora cayetanensis
each sporocyst has 2 sporozoites inside
In which intestinal coccidian can u see an oocyst that is spherical with a greenish central morula (mulberrylike mass) containing 6-9 refractile globules?
Cyclospora cayetanensis
What’s a parasite of cosmopolitan distribution and is able to develop in a wide variety of hosts but its definite hosts are cats?
cats & other Felidae
Toxoplasma
3 ways that a cat may be infected by Toxoplasma?
- Ingestion of infected meat
- ingestion of infective oocyst
- transplacental transmission (vertical transmission)
In humans, the mature (sporulated) oocyst of Toxoplasma will transform into fast-dividing and rapidly-growing intracellular forms called what?
Tachyzoites
The fast-dividing and rapid-growing forms of Toxoplasma may localize in neural and muscle tissue and develop into slow multiplicative forms enclosed in a pseudocyst called?
Bradyzoites
MOT of Toxoplasma gondii in humans
- Ingestion of sporulated oocyst (food or water)
- Ingestion of undercooked meat
- Blood transfusion
- Vertical transmission
All the life cycle stages of Toxoplasma gondii occurs in felines. Only what stages (or forms) can occur in humans and other intermediate hosts?
- Tachyzoites
- Bradyzoites
What form (or stage) of Toxoplasma gondii quickly multiplies and is responsible for initial spread of infection and tissue destruction?
Tachyzoites
What form of Toxoplasma gondii multiplies slowly and form cysts that are more witnessed in chronic toxoplasmosis?
Bradyzoites
Treatment for toxoplasmosis?
pyrimethamine w/ trisulfapyrimidines
for a month
- this inhibits production of dihydrofolate reductase by parasite and DNA, RNA, and protein synthesis
What parasite resembles ring species of Plasmodia and infects RBC + are transmitted by Ixodes?
Ixodes = tick genus
Babesia
What are the two hosts involved in the life cycle of Babesia
Rodents and Ticks
Among the two hosts of Babesia, which is the definitive and which is the intermediate?
- Rodent = intermediate
- Ticks = definitive
In Babesia’s life cycle, humans are considered as what type of hosts?
dead-end hosts
humans r also accidental intermediate hosts only (primrily a zoonotic)
However, human-to-human transmission is well-recognized and seen in blood transfusions
Infective stage of Babesia to intermediate host?
sporozoites
eto rin infective stage to humans
then schizogony sa RBCs then meroz then other meroz will become gametes then ingestion by tick
Diagnostic stage of Babesia?
trophozoites and merozoites arranged in Maltese cross appearance
MOT of Babesia
bite of an infected Ixodes tick
and blood transfusion
Diagnosis for Babesia spp.
- Blood smear (Giemsa-stained)
- IFA
- Immunoblotting
- PCR
Treatment for Babesiosis
Clindamycin + Quinine combination
What dye test is used for Toxoplasma gondii wherein Toxoplasma organisms become resistant to staining with methylene blue if the px’s serum contains Toxoplasma-specific antibodies?
Sabin-Feldman dye Test
(+) = colorless
(-) = blue color
What is the range for the typical Plasmodium vivax and Plasmodium ovale incubation period?
a. 10–17 days
b. 10–12 days
c. 18–40 days
d. 8–11 days
a. 10-17 days
What is the periodicity of the Plasmodium falciparum paroxysm?
a. 44–48 hours
b. 48–50 hours
c. 72 hours
d. 36–48 hours
d. 36-48 hours
What Plasmodium species demonstrate distinct ameboid characteristic?
a. P. vivax
b. P. ovale
c. P. falciparum
d. P. malariae
a. P. vivax
What Plasmodium species demonstrate increase in erythrocytic size upon invasion?
a. P. malariae
b. P. ovale
c. P. falciparum
d. P. vivax
a. P. malariae
honestly, idk bakit ito sagot ni markell eh ang lumalaki lang either vivax or ovale
What malarial parasite is responsible for most of the cases of known nephrotic syndrome?
a. P. malariae
b. P. knowlesi
c. P. falciparum
d. P. vivax
a. P. malariae
What is the mechanism of action of the drug Chloroquine on the malarial parasite?
a. Inhibit ribosomal protein synthesis
b. Inhibit mitochondrial respiratory processes
c. Alter DNA properties disabling parasitic functions
d. None of the above
C. Alter DNA properties disabling parasitic functions
Autofluorescence is an important diagnostic tool for the identification of which of the following organisms?
a. Cyclospora cayetanensis
b. Cryptosporidium parvum
c. Cystoisospora belli
d. Toxoplasma gondii
a. Cyclospora cayetanensis
What constitutes a positive result in the Sabin-Feldman dye test?
a. Agglutination
b. Toxoplasma oocysts stained blue after immersion in methylene blue solution
c. Refractoriness of the oocyst wall to methylene blue staining
d. Loss of color
C. Refractoriness of the oocyst wall to methylene blue staining
Which of the following coccidians is associated with congenital infections?
a. C. parvum
b. C. belli
c. T. gondii
d. S. hominis
c. Toxoplasma gondii
Intraerythrocytic Maltese cross forms are seen in which parasite?
a. P. falciparum
b. B. microti
c. C. belli
d. T. gondii
b.Babesia microti
Most sensitive and accurate method for the detection of C. belli oocysts from fecal specimens.
a. Zinc-sulfate flotation technique
b. Auramine-rhodamine staining
c. Direct microscopic examination
d. Sheather’s sugar flotation technique
d. Sheather’s sugar flotation technique
This coccidian is associated with free sporocysts found in feces due to fragile oocyst walls.
a. C. belli
b. Sarcocystis
c. T. gondii
d. C. cayetanensis
b. Sarcocystis
This organism is characterized as having oocysts ranging from 4 to 6 µm in diameter.
a. C. parvum
b. C. cayetanensis
c. C. belli
d. Sarcocystis
c. C. belli
This was formerly known as cyanobacterium-like body
a. C. parvum
b. C. cayetanensis
c. C. belli
d. Sarcocystis
b. Cyclospora cayetanensis
Which is considered the definitive host for Babesia microti?
a. Humans
b. Ixodes tick
c. White-footed mice
d. Cattle
b. Ixodes tick
The primary means for diagnosing toxoplasmosis
a. Microscopic identification of organisms
b. Cell culture
c. Serology
d. PCR
c. Serology
