Trypanosomiasis

Question 1

Two main form of this protozoal disease are recognised ?

Answer 1

African trypanosomiasis (sleeping sickness)

and

American trypanosomiasis (Chagas’ disease).

Question 2

African trypanosomiasis, or sleeping sickness spread by ?

Answer 2

tsetse fly.

Question 3

African trypanosomiasis, or sleeping sickness/ rypanosoma rhodesiense tends to follow a more acute course. Clinical features include:

Answer 3

Trypanosoma chancre - painless subcutaneous nodule at site of infection

intermittent fever

enlargement of posterior cervical lymph nodes

later: central nervous system involvement e.g. somnolence, headaches, mood changes, meningoencephalitis

Question 4

Mx of Trypanosoma gambiense and Trypanosoma rhodesiense

Answer 4

early disease: IV pentamidine or suramin

later disease or central nervous system involvement: IV melarsoprol

Question 5

x

Question 6

x

Question 7

x

Question 8

x

Question 9

x

Question 10

American trypanosomiasis, or Chagas’ disease, is caused by the protozoan Trypanosoma cruzi, acute phase features ?

Answer 10

asymptomatic in the acute phase although a chagoma (an erythematous nodule at site of infection)

and periorbital oedema are sometimes seen

Question 11

American trypanosomiasis, or Chagas’ disease, is caused by the protozoan Trypanosoma cruzi in chronic phase features

Answer 11

Chronic Chagas’ disease mainly affects the heart and gastrointestinal tract

myocarditis may lead to dilated cardiomyopathy (with apical atophy) and arrhythmias

gastrointestinal features includes megaoesophagus and megacolon causing dysphagia and constipation

Question 12

Mx of trypanosoma cruzi ?

Answer 12

nitroderivatives such as benznidazole or nifurtimox

most effective in the acute phase using