Gram-Weigert Stain Procedure

The Gram-Weigert stain is used to stain the cyst walls of P. carinii cysts. It also stains fungi and many bacteria. Impression 

Rinse the crystal violet from the slide with Gram iodine solution. 

Decolorize the smear in aniline-xylene, agitating the slide gently until no purple runs from it (the use of a second Coplin jar of aniline-xylene after the majority of blue stain has been removed aids the visual assessment of decolorization). 

carinii cysts and fungi stain dark blue and somewhat 

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