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rican trypanosomiasis
American trypanosomiasis (Chagas‟
disease)
– C h ag as‟ d isease is a zoonosis d ue to th e flag ellated protozoan parasite Trypanosoma
cruzi, transm itted to m an by triatom ine bug s (red uv iid ae) th roug h a break in th e skin
or m ucous m em branes. T ransm ission by contam inated blood transfusion and
transplacental transm ission are also possible.
– T h e d isease is only found on th e A m erican continent in th e area betw een th e south of
M exico and th e south of A rg entina.
Clinical features
– Acute phase
• D epend ing on th e inoculation site, th e first sig n is a skin ch ancre or unilateral
purplish orbital oed em a (R om aña's sig n) w ith local lym ph ad enopath y and fev er
(3 8 °C , h ig h er in ch ild ren) ov er sev eral w eeks.
• T h is is follow ed by m ultiple lym ph ad enopath ies, h epatosplenom eg aly, m yocard itis
(ch est pain, h eart failure), som etim es m ening oenceph alitis (seizures, paralysis).
• A cute ph ase m ay be asym ptom atic or subclinical.
T h e transition from th e acute to ch ronic ph ase d oes not alw ays occur.
– Chronic phase
• F ollow s a long latent period after th e acute ph ase: card iac lesions (arrh yth m ia and
cond uction d isord ers, card iom yopath y, h eart failure, ch est pain,
th rom boem bolism ) and g astrointestinal lesions (m eg aoesoph ag us and m eg acolon).
• M ost patients are asym ptom atic.
Laboratory
– Acute phase
• T h in or th ick film : d etection of th e parasite in blood or lym ph nod es.
• Serolog ic tests: d etection of anti-Trypanosoma cruzi antibod ies.
• X enod iag nosis: exam ination of th e faeces of uninfected triatom ine bug fed w ith th e
patient's blood .
– Chronic phase
• Serolog ic tests: d etection of anti-Trypanosoma cruzi antibod ies.
142
American trypanosomiasis (Chagas‟
disease)
– C h ag as‟ d isease is a zoonosis d ue to th e flag ellated protozoan parasite Trypanosoma
cruzi, transm itted to m an by triatom ine bug s (red uv iid ae) th roug h a break in th e skin
or m ucous m em branes. T ransm ission by contam inated blood transfusion and
transplacental transm ission are also possible.
– T h e d isease is only found on th e A m erican continent in th e area betw een th e south of
M exico and th e south of A rg entina.
Clinical features
– Acute phase
• D epend ing on th e inoculation site, th e first sig n is a skin ch ancre or unilateral
purplish orbital oed em a (R om aña's sig n) w ith local lym ph ad enopath y and fev er
(3 8 °C , h ig h er in ch ild ren) ov er sev eral w eeks.
• T h is is follow ed by m ultiple lym ph ad enopath ies, h epatosplenom eg aly, m yocard itis
(ch est pain, h eart failure), som etim es m ening oenceph alitis (seizures, paralysis).
• A cute ph ase m ay be asym ptom atic or subclinical.
T h e transition from th e acute to ch ronic ph ase d oes not alw ays occur.
– Chronic phase
• F ollow s a long latent period after th e acute ph ase: card iac lesions (arrh yth m ia and
cond uction d isord ers, card iom yopath y, h eart failure, ch est pain,
th rom boem bolism ) and g astrointestinal lesions (m eg aoesoph ag us and m eg acolon).
• M ost patients are asym ptom atic.
Laboratory
– Acute phase
• T h in or th ick film : d etection of th e parasite in blood or lym ph nod es.
• Serolog ic tests: d etection of anti-Trypanosoma cruzi antibod ies.
• X enod iag nosis: exam ination of th e faeces of uninfected triatom ine bug fed w ith th e
patient's blood .
– Chronic phase
• Serolog ic tests: d etection of anti-Trypanosoma cruzi antibod ies.
142
