The document describes the Tzanck smear test, which involves scraping skin lesions to examine for Tzanck cells under a microscope. It can help diagnose various acantholytic diseases by identifying certain pathological cell types. Tzanck cells are rounded keratinocytes with a pale halo around the nucleus and darkly stained peripheral cytoplasm. Their presence may indicate conditions like pemphigus, Darier's disease, and herpes simplex virus infection. The test is simple, fast, and inexpensive for screening erosive skin diseases.
2. TZANCK TEST
Introduced by Arnault Tzanck in 1947.
Tzanck smear - scraping of an ulcer base to look
for Tzanck cells.
Simple, fast and inexpensive test used for
screening of acantholytic diseases.
Routine stain : Geimsa
Other stains : PAP, Gram stain
Immunoflorescence
3. TZANCK SMEAR
For viral infections:- the vesicle should be unroofed or
the crust removed, and the base scraped with a scalpel or
the edge of a spatula.
In blistering disorders :- the intact roof of a blister is
opened along one side, folded back and the floor gently
scraped.
In suspected tumors:- any crust should be removed
from ulcerated tumors, and non-ulcerated tumors should
be incised with a sharp, pointed scalpel. A sample of
tumor is then obtained with either a blunt scalpel.
4. KERATINOCYTES
If the cytological sample is taken from normal skin, most
of the cells are anucleated keratinocytes.
5. KERATINOCYTES
On histopatology :- Polygonal or circular cells, are
eosinophilic due to the keratin content in their
cytoplasm.
The N:C favors the cytoplasm.
6. MECHANISM OF ACANTHOLYSIS
Distruption of desmosomes
Desmosomal cadherins :- Homophilic
adhesion
Desmoglein and desmocollin are
transmembranous
Desmoplakin and plakoglobin are
cytoplasmic components
One end of DSG attaches to other DSG
and the other end attaches to PG which in
turns attaches to DP which in turns
attaches to keratin filaments.
7. TZANCK CELLS
In some erosive-vesiculobullous and tumoral
diseases, the keratinocyte cytoplasm shrinks,
becomes rounded, and turns into acantholytic cells,
also called Tzanck cells.
These are round, hyperchromatic nucleated cells
The nucleus/cytoplasm ratio of acantholytic cells
favors the nucleus.
8. TZANCK CELLS
These cells have a perinuclear halo with pale
staining around the nucleus.
9. TZANCK CELLS
The cytoplasm in the periphery is stained more
darkly basophilic and creates an image called as
“mourning edge.”
10. TZANCK CELLS
The diameter of the acantholytic cells is
approximately 2–2.5 times the size of the
lymphocyte
13. BULLOUS PEMPHIGOID
Keratin is not normally found in the cytoplasm of
keratinocytes that have not lost their nuclei.
Keratinocytes that have not lost their nuclei and
have keratin-containing cytoplasm are called
dyskeratotic cells.
The cytoplasm of dyskeratotic keratinocytes stained
with MGG stain has a pinkish appearance due to
keratin accumulation.
15. DARIER’S DISEASE
Rare inherited (autosomal dominant)
Mutation in sarcoplasmic/endoplasmic reticulum
calcium ATPase 2 (SERCA2)
Mutation elicits stress in the endoplasmic reticulum
and induces dyskeratosis, acantholysis, and
apoptosis.
16. DARIER’S DISEASE
Corps ronds are pyknotic nucleated keratinocytes
with a transparent halo around them.
Grains are the smallest apoptotic cells; they are
miniaturized and have the shape of pomegranate
seeds
18. PEMPHIGUS
- Cell surface of acantholytic cells is either flat or contains
sawtooth-like cytoplasmic protrusions.
-Abundant inflammatory cells
- Streptocytes and rosette
