Fite, Leprosy, Animal

Fite, Leprosy, Animal Stained Histology Slide

Validation Stain: Fite


(+) Animal Spleen
Adhesive or Charged Slides: 
Superfrost +

Product Options:

Part # 4212A 10/set $99.30
Part # 4212B 98/set $809.60


Tissue:  Positive staining animal spleen.
Fixation: Formalin 10%, Phosphate Buffered (Part 1090).
Section/Glass: Paraffin sections cut at 4 microns on Superfrost™ Plus slides.
Quality Control Stain:  AFB, Fite quality control stained slide(s) included.
Reactivity: Guaranteed product specific reactivity for one year from date of receipt. Revalidate after one year to verify continued reactivity. 
Storage: 15-30°C in a light deprived and humidity controlled environment.
Intended Use: To verify histological techniques and reagent reactivity.

Before using unstained control slides, review the enclosed stained slide(s) to ensure that this tissue source is acceptable for testing needs.



With AFB, Fite Stain Kit: Part 91013A Individual Stain Solution
Solution A: Xylene/Peanut Oil, 2:1 500 ml Part 1449
Solution B: Carbol Fuchsin Stain, Ziehl-Neelsen 250 ml Part 1030
Solution C: Acid Alcohol 1% 250 ml Part 10011
Solution D: Light Green SF Yellowish 0.1%, Aqueous 250 ml Part 12203



Newcomer Supply Fite, Leprosy, Animal Control Slides are for the positive histochemical staining of Mycobacterium leprae, the causative agent of leprosy.



    1. Heat dry sections in oven according to your laboratory protocol.
    2. Filter Solution B: Carbol Fuchsin Stain, Ziehl-Neelsen with high quality filter paper.



    1. Deparaffinize slides in Solution A: Xylene/Peanut Oil, 2:1, two changes for 10 minutes each.
        1. See Procedure Note #1.
    2. Drain slides, wipe off excess oil, and blot to opacity taking care to remove residual oil.
        1. See Procedure Note #2.
    3. Stain in freshly filtered Solution B: Carbol Fuchsin Stain, Ziehl-Neelsen for 15 minutes at room temperature.
    4. Rinse well in distilled water.
    5. Differentiate slides individually in Solution C: Acid Alcohol 1% until sections are light pink; 5-10 dips.
    6. Rinse well in distilled water.
    7. Counterstain in Solution D: Light Green SF Yellowish 0.1%, Aqueous; 5-10 dips.
    8. Rinse in distilled water.
    9. Blot excess water from slide and air-dry or oven-dry completely.
    10. Dip dried slides in xylene and coverslip with a compatible mounting medium.



Mycobacterium leprae Red
Other tissue elements Green



    1. Acid-fastness of leprosy organisms is enhanced when the waxy capsule is protected by the mixture of xylene/peanut oil and avoidance of dehydrating solutions.
    2. It is important to blot well, residual oil may produce staining artifact.
    3. If using a xylene substitute, follow manufacturer’s recommendation for coverslipping step.



    1. Carson, Freida L., and Christa Cappellano. Histotechnology: A Self-instructional Text. 5th ed. Chicago: ASCP Press, 2020. 215-216.
    2. Fite, George, P.J. Cambre and M.H. Turner. “Procedure for Demonstrating Lepra Bacilli in Paraffin Sections”. Archives of Pathology 43 (1947). 624-625.
    3. Sheehan, Dezna C., and Barbara B. Hrapchak. Theory and Practice of Histotechnology. 2nd ed. St. Louis: Mosby, 1980. 237.
    4. Modifications developed by Newcomer Supply Laboratory.