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33 Cards in this Set
- Front
- Back
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Wear masks Wear gloves Wear aprons Hand wash Take care of sharp objects Proper disposal of waste |
Universal Precautions |
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malaria ; babesiosis |
Specimen suspected of _____ and _____ - blood smears obtained and examined without delay. |
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Parasitemia 8 to 12 hours 2 to 3 days |
_______ - multiple smears might be needed (____ to ____ hour intervals for ___ to ___ days) |
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before |
Specimen collection ______ treatment is initiated |
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exhibit a marked periodicity |
Collection Time Microfilariae - ________ |
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midday (10 AM to 2 PM) |
Collection Time Loa loa - ______ |
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at night, after 8 PM |
Collection Time Brugia or Wuchereria - ________ |
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Anytime |
Collection Time
Mansonella - _____ |
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any time |
Collection Time Onchocerca - ______ |
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Venous blood samples |
Type of Sample
primarily used and provide sufficient material for performing a variety of diagnostic tests. |
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Capillary blood samples |
Type of Sample preferable when the anticoagulants interfere with parasitic morphology and staining. |
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Thick smears |
- thick layer of dehemoglobinized (lysed) red blood cells (RBCs). - blood elements are more concentrated (30 times) than in an equal area of a thin smear. - allow a more efficient detection of parasites (increased sensitivity). |
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size of a dime (1.5 cm2) |
Size of Thick Smear |
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can take several hours - 30 minutes is the minimum |
Drying for Thick Smear |
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20 to 30 minutes |
Time for Scratch method in thick smear |
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Thin smear |
consist of blood spread in a layer such that the thickness decreases progressively toward the feathered edge. |
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30°-45° |
Angle for thin smears |
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absolute methanol |
Fix the thin smears by dipping them in ____. |
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Wright (Wright-Giemsa) Stain |
Used in hematology, this stain is not optimal for blood parasites. |
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Giemsa stain Schüffner’s dots |
Wright stain can be used if rapid results are needed, but should be followed up when possible with a confirmatory ______, so that _______ can be demonstrated. |
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Giemsa stain |
Stain recommended for detection and identification of blood parasites. |
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2.5% ; 45-60 minutes |
Place slides (blood smear) into the working Giemsa stain (___%) for ____ minutes. |
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3-4 |
Remove thin smear slides and rinse by dipping ___ times in the Giemsa buffer |
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5 minutes |
Thick smears should be left in the buffer for ______. |
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10 minutes in 10% Giemsa |
The smears could be stained for shorter times in more concentrated stains. One alternate is ________ – (use of more stain might be of less predictable quality) |
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EDTA ; one ; 2-3 |
Staining: Quality Control
Choose a patient blood specimen, anticoagulated with ____, (at least ___ parasite in every ___ field) |
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-70°C |
Store Giemsa control slides at ____ (or colder) |
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10-20 WBCs/field |
Microscopic examination of Thick Smear
Number of WBCs per field to be examined
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at least 100; 20 WBCs |
Microscopic examination of Thick Smear
Determination of "No Parasites Found" (NPF): For malaria diagnosis, WHO recommends that ______ fields, each containing approximately _____, be screened before calling a thick smear negative |
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300; 100x oil immersion |
Microscopic examination of Thick Smear
CLSI standards recommend examination of at least ___ fields using the _______ objective. |
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8000 |
Determination of Parasitemia Thick smears standard number of WBCs |
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500 |
Determination of Parasitemia A minimum of ___ RBCs total should be counted in thin smears. |
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Gametocyte |
Determination of Parasitemia In thin smears, _____ are not figured in calculations. |
