Blood Parasite Smear Examination

Test performed at York Hospital Laboratory. Preferred collection sites are the York and Wells Laboratories due to limited specimen stability. Used for identifying Plasmodium species and Babesia microti. Ehrlichia are rarely seen in peripheral smears. Other serological testing should be ordered if Ehrlichiosis is suspected.

BP

Parasite Smear, Blood

2 Thick and 2 Thin Blood Smears from fingerstick

1 mL whole blood collected in an EDTA (lavender-top) tube

EDTA tubes submitted for blood parasite smears must be received in the laboratory within 45 minutes from collection.

Room temperature

Room temperature (whole blood): 1 hour
Refrigerated: Unacceptable
Frozen: Unacceptable

EDTA tubes received after 1 hour from collection

Daily

2 Days

None Seen Critical Values Parasites Seen

Thick and thin blood smears are used to determine the presence, type and percentage of RBCs infected with heither malaria or babesiosis and (outside of the RBCs - extracellular) filariasis, and trypanosomiasis. Blood smears are the most reliable tests for determining the presence of malaria. Differentiation of P. falciparum from B. microti is essential for proper treatment. The main species of Babesia, in the United States, is the protozoan B. microti.

Ehrlichia are obligate intracellular bacteria that are seen as inclusions called morula in monocytes and granulocytes. Thse morula are rarely seen in peripheral smears. Serological testing is recommended if Ehrlichiosis is suspected.