Coccidia

Question 1

Phylum_____

•____ forming, microscopic,____-celled parasites

•____ intracellular protozoanà need host cell to reproduce

Answer 1

Apicomplexa

Spore

single

Obligate

Question 2

Infects_____

– Causes severe____

–____ as diagnostic specimen

–______: confirmatory

Answer 2

gastrointestinal tract

diarrhea

Stool

Stool Culture

Question 3

Disease:

–______ disease

– Host specific, EXCEPT_______ (all mammals)

Answer 3

Coccidiosis

Toxoplasma gondii

Question 4

•______ in immunocompromised hosts

– AIDS patients, transplant patients, malnourished children

• May be______ in immunocompetent individuals

Answer 4

Opportunistic

asymptomatic

Question 5

Members

Answer 5

1. Isospora
2. Cyclospora
3. Cryptosporidium
4. Toxoplasma
5. Sarcocystis

Question 6

Alternation of sexual and asexual multiplication

• 3 sequential stages:

1.______ producing micro- (male) and macro-(female) gametocytes (gamonts)

2. Sexual cycle or_____ producing oocyst containing sporozoites
3. Asexual cycle or_____ producing merozoites (meronts)

Answer 6

Gametogony

Sporogony

Schizogony

Question 7

Humans are the only known hosts

Answer 7

Cystoisospora/Isospora belli

Question 8

Cystoisospora/Isospora belli

Transmission:

– ingestion of_______

• (sporulated oocyst contains___ sporocysts each containing___ sporozoites)

• Sporulation of oocyst in food or water

Answer 8

MATURE OOCYST

2; 4

Question 9

Cystoisospora

Habitat:

Answer 9

distal duodenum and proximal ileum

Question 10

Cystoisospora

• Microgametes fertilizes the macrogamete and forms the_______ à passed out through the feces

•_______: Embyronic element divides inside the oocyst and forms the 2 sporoblasts

• Sporoblasts matures into______ containing 4 sporozoites each

• Sporulated oocyst is ingested and releases______

• Sporozoites infects intestinal cells where it undergoes______ to produce merozoites

• After several schizogony, some merozoites differentiate and undergo______ to form the microgamete and macrogamete

Answer 10

unsporulated oocyst

SPOROGONY

sporocysts

sporozoites

SCHIZOGONY

GAMETOGONY

Question 11

Cystoisospora

Asexual and sexual development occur in one host

•________
– Mature oocyst (containing 2 sporocysts, each with 4 sporozoites) when ingested release sporozoites invading intestinal cells of small intestine > trophozoite > merozoites

•________
– Some merozoites develop into macro- and microgametocytes > zygote > ocyst which are passed out with feces and undergo maturation in the environment

Answer 11

Asexual (schizogony)

Sexual (sporogony)

Question 12

– prolonged mild diarrhea (sometimes lasting for 6 months), abdominal pain, fever, malaise, flatulence

– Malabsorption syndrome with weight loss

– Dissemination of parasites to other organs in AIDS patients

Answer 12

Cystoisosporiasis

Question 13

Oocyst of I. belli

• A._____
– elongate and ovoidal
– 20-33 u x 10-19 u

• B. ____ with two Sporoblasts

• C.____

– Sporocysts with 4 long and slender sporozoites each

Answer 13

Immature Oocyst

Immature Oocyst

Mature with Sporocysts

Question 14

Cyclospora cayetanensis

• Originally,______-like body (CLB)

– Photosynthesizing organelles and autofluorescing particles characteristic of blue green algae

• Transmission:
– Ingestion of_____
• 2 sporocysts with 2 sporozoites each

• Habitat:
–______

Answer 14

cyanobacterium

MATURE OOCYST

Small intestine, with jejunum as predilection

Question 15

Cyclospora cayetanensis

• Ingestion of____ oocyst

• Oocyst releases____ in the intestine

• Sporozoites invade epithelium of small intestine (predominantly jejunum

Answer 15

sporulated

sporozoites

Question 16

Cyclospora

Sporozoites undergo merogony

1. First generation:
   Meronts contain____ merozoites
2. Second generation:
   Meronts contain___ merozoites

• Some merozoites develop micro- and macrogamete

Answer 16

8-12

4

Question 17

•

– Mature oocyst (containing 2 porocysts, each with 4 sporozoites) when ingested release sporozoites invading intestinal cells of small intestine: JEJUNUM àmeronts I (8-12)à meronts II (4)

Answer 17

Asexual (schizogony)

Question 18

– Some merozoites develop into macro- and microgametocytesà zygote à unsporulated oocyst with feces à maturation in warm environment

Answer 18

Sexual (sporogony)

Question 19

Generally, self-limiting

– IMMUNITY w/ repeated infections

Answer 19

Clysospora

Question 20

Other Symptoms

– Fatigue, anorexia, weight loss, nausea, vomiting, abdominal pain, flatulence, bloating, and dyspnea

• D-xylose malabsorption: proximal small intestine malabsorption

• NO DEATHS reported

Answer 20

Clysospora

Question 21

Clysosporis
Diagnosis

• Direct microscopic examination
• Concentration technique
• Acid fast staining (_____stain)

•______: autofluorescent

– Fluorescent microscopy:
____ or _____
• Polymerase chain reaction

Answer 21

Kinyoun’s stain
Oocyst
blue or green circles

Question 22

• Infects humans (opportunistic) and other animals

• Intracellular, extracytoplasmic (brush borders)

• Transmission:

– ingestion of thickwalled oocysts from the environment, pets and farm animals

Answer 22

Cryptosporidium

Question 23

Habitat:

– GIT

• 2 species

Answer 23

– Cryptosporidium hominis (mainly in humans)

– Cryptosporidium parvum

Question 24

Humans passed out as he awaits thickwalled oocyst

• Oocyst is already mature upon passing out

• When ingested, oocyst releases 4 sporozoites which infects intestinal cells

• Sporozoites undergo SCHIZOGONY to produce merozoites type 1 (8 daughter cells)

Answer 24

Cryptospordium

Question 25

All stages of development are completed in the gastrointestinal tract of the host

Answer 25

Cryptospordium