Lab Test

Smear, Blood Parasites

Malaria, Babesia, Microfilariae, Trypanosoma, Trypanosomes, Leishmania, Leishmoniasis, Ehrlichia, Ehrlichiosis, Chagas Disease, Sleeping Sickness, Tse Tse Fly, Plasmodium, Anaplasma, Anaplasmosis

Test Codes

EPIC: LAB5522

Department

Microbiology

Instructions

Blood specimens must be sent to the laboratory immediately after collection. Delays in specimen transport can cause changes in parasite morphology and staining characteristics. The patient’s travel history should also be included to aid in test interpretation.

Specimen Collection Criteria

Collect: One Lavender-top EDTA tube via venipuncture. Immediately mix well by gently inverting several times.

Send specimens to the Microbiology Laboratory immediately after collection. All specimens for Blood Parasite testing should be placed in a STAT bag for delivery to the Laboratory - this process will help ensure that the specimen is received in the Microbiology Laboratory in a timely manner.

  • If submitted at the Grosse Pointe campus send specimen to tube station #5.
  • If submitted at the Royal Oak campus send specimen to tube station #325.
  • If submitted at the Troy campus send specimen to tube station #201, #300, or #810.
  • If submitted at the Farmington Hills campus, send the specimen to tube station #2 OR bring the sample to Laboratory Central Processing department (LCP).

Rejection Criteria

Coagulated blood or use of an anticoagulant other than EDTA, (e.g. heparin or sodium citrate).

In-Lab Processing

Blood smears should be prepared as soon as possible after collection (delay can result in changes in parasite morphology and staining characteristics).

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 24 hours, 1 hour (preferred)
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

EDTA Tube: Refrigerated (2-8°C or 36-46°F): 7 days
Slides: Room Temperature (20-26°C or 68-78.8°F): 7 days

Laboratory

Dearborn Microbiology Laboratory
Farmington Hills Microbiology Laboratory
Grosse Pointe Hematology/Microbiology Laboratory
Royal Oak Microbiology Laboratory
Taylor Microbiology Laboratory
Trenton Microbiology Laboratory
Troy Hematology/Microbiology Laboratory
Wayne Microbiology Laboratory

Performed

Sunday – Saturday, 24 hours a day.
Malaria antigen test results available within 2 hours.
Thin smear results available within 4 hours.
Thick smear results available within 1-2 business days.

Reference Range

No blood parasites detected.

Test Methodology

Rapid Antigen Test (BinaxNow) for Malaria. Microscopy of stained thick and thin blood films.

Interpretation

  • The Malaria Antigen Test provides a rapid result for the presence or absence of P. falciparum or other Plasmodium species. Thin and thick blood films will still be performed because:
    1. the Malaria Antigen Test can remain positive up to 30 days following effective treatment.
    2. calculating the percent parasitemia from the thin blood film is necessary.
    3. to ensure the accurate species-level identification of malaria (when present).
    4. patients with rheumatoid factor may yield a false positive Malaria Antigen Test.
    5. the ability to detect other blood parasites.
  • The thick film allows for concentration of the blood to facilitate the detection of the parasite which may be present in small numbers. Species identification is usually performed on thin films (1).

Clinical Utility

This test aids in the diagnosis of blood parasites.

Clinical Disease

  • Blood parasites, including the genera of Plasmodium, Babesia, Trypanosoma, Leishmania, Brugia, Loa, Mansonella, Onchocerca, and Wuchereriai are a major cause of human morbidity and mortality.
  • These parasites may be seen in various circumstances, including immunocompromised hosts, immigrants, travelers to and from endemic areas, and military personnel.
  • Malaria is one of few parasitic infections deemed a medical emergency due to it's associated morbidity and mortality, and, in the case of infections due to Plasmodium falciparum, rapidly fatal. Plasmodium species commonly infect the liver, lungs, brain, and microvasculature, leading to life-threatening complications. As such, the laboratory must be able to provide species-level identification as rapidly as possible to facilitate appropriate anti-parasitic therapy.
  • The detection and species-level identification of blood parasites is best facilitated by careful examination of Giemsa-stained thin- and thick-blood films, that should be prepared as quickly as possible from whole blood or from the sediment of a variety of concentration procedures.

Reference

  1. Garcia, L.S. 2007. Malaria and Babesiosis. Diagnostic Medical Parasitology, 5th ed. ASM Press. Washington, D.C., pp.142-189.

CPT Codes

87015, 87207x2, 87899, 87899-59.
LOINC:  662-7, T1/T2 70569-9

Contacts

Last Updated

5/19/2023

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