Trypanosoma (lecture)

Question 1

What two diseases covered in class are caused by Trypanosoma?

Answer 1

Chagas Disease (Americas) - T. cruzi
African Sleeping Sickness (Africa) - T. brusei

Question 2

What species of trypanosome is intracellular?

Answer 2

T. cruzi (Chaga’s)

Question 3

What unique structure of Trypanosoma is closely associated with its flagella and is used in diagnosis?

Answer 3

Kinetoplast is a DNA containing structure that has an ill-defined function, but resembles mitochondrial DNA of other organisms.

Question 4

What is the primary world wide vector of Trypanosoma?

Answer 4

Kissing bug

http://abcnews.go.com/Health/dangerous-chagas-infection-kissing-bug-found-states/story?id=35414947

Question 5

What is the mostly likely cause of death associated with T. cruzi?

Answer 5

Cardiovascular disease from heart worms that cause cardiomyopathy

Question 6

Impoverished Brazilian with unilateral painless periorbital swelling (Romanas sign) and 5 cm swelling on her right forearm. A flagellated C shaped parasite is noted on blood smear. A widened QRS is also noted on ECG. What is the likely vector and most likely cause of death if left untreated?

Answer 6

This is classic T. cruzi presentation (Chaga’s), most likely T. cruz due to the location (South America).
Most likely cause of death is cardiomyopathy

Question 7

What complication of Trypanosoma infection are immunocompromised patients at increased risk of developing?

Answer 7

Brain abscess-like infection (it is filled with worms)

Question 8

How can Trypanosoma cause GI distress?

Answer 8

It is known to cause megacolon and esophageal dilation

Question 9

What is first line treatment for acute Chagas?

Answer 9

Benznidazole

Question 10

West African teenager reports with recurrent fevers over the last 4 months. He reports an increase in malaise and weight loss. C shaped extracellular organisms are noted on blood smear. What is the subspecies of the causative agent? What is the pathophysiology of the recurrent fevers? What is the most likely source of the disease? What is the prognosis if left untreated?

Answer 10

This is African Sleeping Sickness, caused by T. brucei. Slow developing is usually caused by gambiense (more prevalent in W. Africa).
The recurrence is due to antigenic shift of the parasite.
The tse tse fly is the the vector in Africa.
Patients usually die within 2 years if not treated (CNS involvement).

Question 11

What subspecies of Trypanosoma are travelers at increased risk of contracting? How does disease progression with this compare to the type found in the local population?

Answer 11

Travelers - T. brucei rhodesiense

This rapidly progressing compared to gambiense