[Last Modified: ]

September 2003
Answer to Case 115
This was a case of Chagas Disease (American trypanosomiasis) caused by an infection with Trypanosoma cruzi and was acquired due to organ transplantation.  Diagnostic features observed included:

• a trypomastigote of T. cruzi with an undulating membrane.
• the presence of a prominent, posteriorly-located oval kinetoplast (blue arrow) and a nucleus, usually situated in the center of the body (red arrow).
• the size of the organism, which was in the size range for T. cruzi (approximately 20 micrometers, range 12-30 micrometers).

It should be noted that Trypanosoma rangeli can also infect humans in the Americas, overlapping the geographic distribution of T. cruzi infections.  However T. rangeli has a smaller kinetoplast and is usually longer and more slender (average length of 30 micrometers) than T. cruzi.  There is no pathology associated with T. rangeli infections in humans.

A

For more information regarding this interesting case, click here for a MMWR article on the topic.
For more information on American trypanosomiasis, please click here.