Public Health and Environmental Laboratories

Harvest Order Choice: 60010, 60000

Synonyms:

Program: Microbiology

Unit: Special Bacteriology                  

Useful For: Determination of presence and the identification of blood parasites

Method: Microscopy

Charge: N/A

Request Form: BACT-109

Container/ Tube: slides or purple top tube

Type: Blood, Stained or unstained thick and thin blood smears

Volume: N/A

Collection Instructions: Venipuncture blood; smears should be prepared within an hour of blood collection. If a slide cannot be made, store the blood at 2-8 C for no more than 4 days. Unstained thick and thin slides made directly from fresh capillary or fresh EDTA blood are died before shipment to the Public Health and Environmental Laboratories. The EDTA blood specimen may also be shipped in case additional slides or PCR tests are needed/

Storage: Malaria/ Babesia stained and mounted slides can stay at room temp. for one year. If slide cannot be made blood tube can be stored at 2-8C for 2-4 days.

Causes for Rejection: Broken slides, clotted blood

Interpretation: There are four Plasmodium species, which infect humans. It is important to correctly identify the species in order to appropriately treat the patient’s infection. The parasites are usually found within the the erythrocytes. Reports of Plasmodium are made by Genus and Species, whereas Babesia is identified at the genus level. Also % Parasitemia included in the report.

Appearance of Malaria or Babesia Parasites:

1. Cytoplasm
2. The cytoplasm us blue and may vary from pale to deep blue, depending on the species and life-cycle stage
3. Nucleus (Chromatin)
4. The nucleus is red and may vary from pink to maroon, depending on the species and life-cycle stage
5. PigmentNOTE: Pigment may also be seen ingested by white blood cells. Note that Babesia sp. Does not produce pigment and can be seen outside of the RBC
6. A waste product of hemoglobin metabolism may be present in the cytoplasm of trophozoite and later-stage parasites of Plasmodium sp. And can vary from golden-brown to black, depending on the species
7. Erythrocytes (RBCs)B: The cytoplasm may contain small pink-to-red rodlike inclusions, called “maurer’s clefts”, as in P. falciparum-infected erythrocytes
8. C: small blue specks in the cytoplasm (or a homogenous bluish tinge) are found in reticulocytes, immature erythrocytes and may be present in uninfected or infected erythrocytes
9. A: The cytoplasm may contain pink stippling, called Shüffner’s dots, in Plasmodium vivax- or P. ovale-infected erythrocytes

Reference Interval: Negative

Limitations: To detect stippling and ensure good parasite morphology, the smears should be prepared within one hour after the blood was collected. After that time, Shüffner’s stippling and other dots may not be visible on stained films; the absence of stippling may make malaria species identification more difficult. However, the overall organism morphology should still be excellent if the smears are prepared within two hours, providing the smears are stained correctly.

Availability: N/A