Monthy Case Studies - 2000
Case #33 - April, 2000
A 12-year-old Nicaraguan girl, who recently immigrated with her family to the United States, was seen in a regional health center for nonspecific malaise and fever. No background information regarding the family's living conditions in Nicaragua was available (i.e., rural vs. urban). An examination, including preparation of blood films, was performed. Examination of the Giemsa stained thin blood smears revealed small, flagellate-like organisms (Figures A, B, C, and D). What is your diagnosis? Based on what criteria?
Answer to Case #33
The objects in this case were artifacts. Most likely, the artifacts were platelets that resembled trypanosomes. Platelets on a stained blood film can appear amoeboid and even seem to have a flagellum. The features of the artifacts that clearly ruled out trypanosomes were:
- the small size. These objects were an average of eight micrometers. Trypanosoma cruzi, which was the suspected organism, averages about 20 micrometers, yet can range from 12 to 30 micrometers.
- the lack of a distinctive nucleus, kinetoplast, or true flagellum. The objects appeared to be homogenous in composition, with no apparent internal structures.
In the images below, we have compared one of the objects with an image of two T. cruzi trypomastigotes to show the differences.
More on: Artifacts
Images presented in the monthly case studies are from specimens submitted for diagnosis or archiving. On rare occasions, clinical histories given may be partly fictitious.