CNS Protozoa

Question 1

CNS Protozoa include:

Answer 1

• Trypanosoma brucei gambiense/rhodesiense (Sleeping Sickness)
• Toxoplasma gondii.

Question 2

Trypanosoma brucei gambiense/rhodesiense spread by? Life cycle?

Answer 2

Tsetse fly

• Parasite moves to salivary glands
• Inject Metacyclic Trypomastigote into host
• Binary fission in blood

Question 3

How does Trypanosoma brucei gambiense/rhodesiense evade the immune system?

Answer 3

Antigenic variation of surface glycoproteins, immunologically privileged sites, immune suppression

Question 4

Beginning of Trypanosoma brucei gambiense/rhodesiense:

Answer 4

• Small sore at inoculation site
• Winterbottom’s sign (swollen lymph nodes at base of neck)
• Undulant fever (parasites increase and decrease in blood)

Persists 2-3 weeks until sleeping sickness

Question 5

Sleeping sickness in Gambiense:

Answer 5

• Move to CNS in 1 year
• Fever/headache, apathy, sleep, coma, death
• 2-3 years total if untreated

Question 6

Sleeping sickness in Rhodiense:

Answer 6

• Move to CNS in 1 month

- Coma, death in 9-12 months if untreated

Question 7

Diagnosis / Treatment for Trypanosoma brucei gambiense/rhodesiense?

Answer 7

Demonstrate parasite in blood/lymph/CNS

Suramin BEFORE CNS affected
Melarsoprol / Eflornithine AFTER CNS affected

Question 8

Life cycle of Toxoplasma gondii?

Answer 8

• Oocysts in cat feces or pseudocysts in raw meat (or transplacental)
• Asexual dissemination
• Form in brain, liver, eyes

Develop immunity; latent in pseduocysts
- Can re-emerge in immunocompromised patients (fatal)

Question 9

Congenital toxoplasmosis:

Answer 9

• Still birth
• Severe brain damage (hydrocephalus, calcifications)
• Seizures
• Eye damage (chorioretinitis)

Question 10

Diagnosis / Treatment of Toxoplasma gondii:

Answer 10

Antibody in serum - Toxo Serologic Profile (TSP)
- do twice to detect active infection

Pryimethamine and sulfadiazine
Spiramycin to pregnant women