Sarcocystosis

Question 1

If Sarcocystosis infect between Snake and Man, who is the definitive host and intermediate host?

Answer 1

Snake is definitive host
Man is intermediate host

Question 2

If Sarcocystosis infect Cow, Pig and Man, who is the Definitive and Intermediate host?

Answer 2

Man is Definitive Host
Cow is Intermediate Host
Pig is Intermediate Host

Question 3

If man as IH where snake is DH, where is the pathology?

Answer 3

Muscular

Question 4

If man as DH where pig and cow is IH, where is the pathology?

Answer 4

Intestinal

Question 5

What is the mode of infection if intestinal is infected?

Answer 5

eating meat infected with cyst containing Bradyzoite

Question 6

What is the mode of infection if muscular is infected?

Answer 6

eating oocyst/sporocyst

Question 7

Explain the life cycle of Sarcocystis sp. where man is the IH and snake as the DH

Answer 7

• Snake ingested tissue cyst containing mature Sarcocystis sp.
• The cyst release sporozoite which then enter intestinal epithelial cells and undergo asexual reproduction (schizogony)
• Resulting in formation of merozoites that can develop into male and female gametocytes which then will undergo sexual reproduction forming zygote
  -Zygotes will develop into oocyst with thick-walled structure which shed in the faeces.
• Man as ID will ingest the oocyst thru contaminated water and soil. Upon ingestion, oocyst release sporozoites, invade the epithelial cells of GIT.
  -Sporozoites develop into schizont (schizogony) which release merozoites and mature into sarcocyst containing bradyzoites.
  -Sarcocyst will develop in the muscle

Question 8

What is the presentation of man as IH ?

Answer 8

myositis, muscle tenderness

Question 9

Explain the life cycle of Sarcocystis sp. where man is the DH?

Answer 9

• Man ingested cyst with bradyzoite in undercooked meat
  -Bradyzoites are released and enter intestinal cells undergo sexual reproduction forming microgamete or macrogamete.
• It fertilizes and become immature oocyst and exit the host
  -Sporocysts and thin-walled oocyst passed in the faeces and ingested by cow and pig
  -Sporocyst ruptures releasing sporozotes that enter endothelial cells of blood vessels and undergo schizogony.
  -Schizont rupture releasing merozoites.
  -Merozoites invade muscle cells and develop into cysts with bradyzoites.

Question 10

What is the symptom of infected man as DH?

Answer 10

Asymptomatic or mild non-specific symptoms

Question 11

What is the Sarcocystis sp. infect the cattle and pig?

Answer 11

S . hominis – cattle
S. Suihominis - pig

Question 12

One sporocyst of Sarcocystis sp. have how many sporozoites?

Answer 12

4 sporozoites

Question 13

How much sporocyst in one oocyst in Sarcocystis sp. ?

Answer 13

2 sporocyst in each oocyst

Question 14

How to diagnose Sarcocystis sp. in an infected man?

Answer 14

1. Travel history – tropical country (SEAsia)
2. Histology tissue sample - cysts in muscles.
3. Stool analysis - oocyst with sporozoites in faeces (if intestinal sarcocystis)
4. Serology - Seropositivity is high among Orang Asli, in Malay, Chinese and Indian

Question 15

What is the treatment can be given?

Answer 15

No known treatment

Question 16

What are the local and generalized symptoms for muscular sarcocystis?

Answer 16

Local symptoms man:
-Asymptomatic – finding at autopsy
-myositis
-Muscle tenderness
-Associated with cystic changes in striated muscles.

Generalized symptoms man:
-Fever, headache, fatigue
-Dyspnea and wheezing – is lung is affected

Question 17

What are the species of Sarcocystis sp. can infect man as IH?

Answer 17

S. nesbatti
S. lendenmani