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- Parasite Classification | - Parasite, Body Site |
- Stool Testing Order Recommendations | - STAT Testing |
- Fecal Fixatives | - Stool Collection Options | - Report Comments |
- Tips for Fecal ImmunoAssay | - Malaria (5 Species) |
- Malaria (5 Species) Images | - Rapid Malaria Testing |
- Malaria Parasitemia Method | - Malaria Parasitemia Interpretation |
- USE OF A REFERENCE LABORATORY FOR PARASITE BLOOD DIAGNOSTIC TESTING (Including the Binax Rapid Test and Report Comments)

- HELMINTH PARASITES ASSOCIATED WITH EOSINOPHILIA | - Histology: Staining Characteristics - Table 1 | - Histological Identification of Parasites - Table 2 | - Microscope Calibration | - Figures for Histology Identification Table 2
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USE OF A REFERENCE LABORATORY FOR PARASITE BLOOD DIAGNOSTIC

TESTING (Including the Binax Rapid Test and Report Comments)

There are several important considerations when using a reference laboratory for blood parasite diagnostic testing. Different laboratory situations are presented below with recommendations for reference laboratory use.

  1. If your test timing does not consider STAT testing time limits for blood parasite diagnostic work, this test option should not be listed as an available test on your test menu.
  2. If you make the test available to your physicians, the following guidelines should be considered:
    1. Blood film examination for parasites should be ordered on a STAT basis (ordering, collection, processing, examination, and reporting).
    2. Even if the blood films will be sent to a reference laboratory, the laboratory handling blood collection should do the following:
      1. Examine the blood films on site with a report sent to the physician (STAT basis). At the same time, send the original lavender (EDTA) blood tube with thick and thin blood films prepared at the time the blood was received in the collecting laboratory (stained or unstained). These thick and thin blood films eliminate the potential problems with lag time between when the blood was collected and the blood films were made. If no blood films are prepared prior to shipment to the reference laboratory, organism distortion (after 1 h) and disintegration (after 6 h) tend to occur. If the blood films are unstained, the thin films should be fixed (absolute methanol) prior to shipment.
      2. If the collecting laboratory performs a STAT dipstick malarial rapid test (Binax NOW Malaria test kit, Inverness Medical/Binax, Scarborough, Maine), the following steps are relevant. The rapid test should be performed immediately on receipt of the blood (STAT). If positive, the result and interpretation should be sent to the physician. If the BinaxNOW is negative, the result should be reported to the physician. HOWEVER, at the same time, the laboratory is responsible for examining and reporting the results of thick and thin blood films (STAT basis), even if the blood is being sent to a reference laboratory.
      3. It is critical to understand the BinaxNOW limitations in patients with a low parasitemia; these patients may present with a false negative rapid test. These patients are often travelers who are symptomatic at a very low parasitemia. THIS NEGATIVE BinaxNOW RESULT DOES NOT RULE OUT A BLOOD PARASITE (Plasmodium/Babesia). THESE LOW PARASITEMIA CASES WILL ALSO NOT BE DETECTED USING HEMATOLOGY AUTOMATED SYSTEMS.

BLOOD FILM REPORTING WITH ADDITIONAL REPORT COMMENTS

Additional report comments can be extremely valuable for the physician. Various examples (underlined), reports, and report comments are seen below:

  1. Negative thick and thin blood films: No blood parasites seen. One set of negative blood film will not rule out Plasmodium or Babesia.
  2. Plasmodium seen, not identified to species: Plasmodium spp. seen. Unable to rule out Plasmodium falciparum or Plasmodium knowlesi. NOTE: In this circumstance the presence or absence of gametocytes could not be confirmed (this is another comment that should be added); the answer yes/no will influence therapy.
  3. Plasmodium seen, good morphology, unable to identify to species: Plasmodium spp. seen. Unable to rule out Plasmodium falciparum or Plasmodium knowlesi. No gametocytes seen. NOTE: If morphology allows/does not allow identification to Plasmodium genus, provide parasitemia for the physician.
  4. Plasmodium vivax seen (including gametocytes); possible other unidentified species present:Plasmodium vivax (including gametocytes) seen; possible mixed infection. Unable to rule out Plasmodium falciparum or Plasmodium knowlesi.
  5. Plasmodium falciparum seen, rings only: Plasmodium falciparum seen (no gametocytes seen); make sure you report parasitemia for all cases of positive Plasmodium spp.