(c) Procedure. Mix one or two milligrams of feces with a drop of the MIF
solution. Allow the mixture to stand for a few minutes so that the organisms stain well.
Examine for the presence of diagnostic forms of intestinal parasites.
(4)
Supravital Stain.
(a) Stock reagents.
1 Solution A (Eosin in isotonic saline).
Eosin Y, analyzed reagent ........................... 0.5 gm
Physiological saline ..................................... 100.0 ml
Add the Eosin stain powder slowly to the saline while stirring and
filter the solution after all the eosin has dissolved. Store in a
screw cap bottle.
2 Solution B (Brilliant Cresyl Blue in isotonic saline).
Brilliant Cresyl Blue, analyzed reagent ........ 0.2 gm
Physiological saline ..................................... 100.0 ml
Mix filter and store as in solution A.
(b) Working reagent. Immediately before use, mix equal parts of
Solutions A and B, but only in the quantity needed for that particular staining procedure.
(c)
Procedure for feces.
STEP 1: Place one drop of the Eosin-Brilliant Cresyl Blue stain in the center of a 25 by
75 millimeter glass slide.
STEP 2: Use the end of a plain applicator stick to pick up a small quantity of feces from
a passed stool. A portion taken from an area with mucus or flecks of blood is
more likely to contain trophozoites.
STEP 3: Transfer the selected bit of fecal material to the drop of stain and mix until a
thoroughly homogenous suspension is formed.
STEP 4: Cover the suspension with a 22 by 40 millimeter coverslip, avoiding formation
of air bubbles and macroscopic debris, and place the slide on a warming
apparatus at 37 for a minute before microscopic examination. This allows time
for the supravital stain to effectively penetrate the organisms while the heat
from the warming apparatus stimulates locomotion.
MD0841
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