(d) Procedures for rectal scrapings.
STEP 1: If the material to be examined is obtained from a rectal proctoscopy, it must be
rushed to the laboratory in a clean, 84 milliliter wide mouth, screw cap bottle
that has been warmed to 37 C. Immediately upon laboratory receipt, place
the specimen on a warming table and keep at 37 C until completion of
examination.
STEP 2: Use a small disposable pipette to aspirate a small portion of the mucoid
proctoscopic material.
STEP 3: Put two drops of stain on a clean slide and mix the fecal aspirate with the stain
by repeatedly drawing up and expelling the suspension upon the slide.
STEP 4: After thoroughly mixing, leave a large drop on the slide and proceed as in step
(4) for feces.
(5) Quensel's solution. Amoebic trophozoites are not easily identified using
the saline preparation. Stains such as iodine are not suitable for the identification of this
stage because it is completely distorted by the stains. Rapid demonstration of motile
trophozoites on wet mount slide preparations can be achieved by the use of Quensel's
solution. This preparation may be used on fresh or cultured specimens.
(a) Stock reagents.
1 Sudan III--solution A.
Sudan III powder.......................................... 1.6 gm
Ethanol, 80% ............................................... 100.0 ml
Mix the stain with the alcohol and shake well. Allow the mixture
to stand overnight to ensure that the solution is saturated. If at
the end of 24 hours the stain has completely dissolved, add more
Sudan III powder until saturation. Filter and store in a stoppered
brown glass bottle.
2 Methylene blue--solution B.
Methylene blue powder (medicinal) ............. 3.5 gm
Distilled water .............................................. 100.0 ml
Mix the powder with water and shake well. Allow the mixture to
stand overnight to ensure that the solution is saturated. If at the
end of 24 hours the stain has completely dissolved, add more
Methylene blue powder until saturation. Filter and store in a
stoppered brown glass bottle.
MD0841
2-42