In Pemphigus vulgaris, tzank smear shows –
**Core Concept**
Pemphigus vulgaris is an autoimmune disease characterized by the formation of blisters on the skin and mucous membranes due to the presence of autoantibodies against desmoglein 3 proteins, which are components of desmosomes that hold skin cells together.
**Why the Correct Answer is Right**
The Tzank smear is a diagnostic test used to detect the presence of acantholytic cells, which are individual keratinocytes that have lost their intercellular connections due to the breakdown of desmosomes. In Pemphigus vulgaris, the autoantibodies against desmoglein 3 proteins lead to the disruption of desmosomes, resulting in the formation of acantholytic cells. These cells are characteristic of Pemphigus vulgaris and can be seen on a Tzank smear.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not describe the characteristic finding of Pemphigus vulgaris on a Tzank smear.
**Option B:** This option is incorrect because it is a feature of Pemphigus foliaceus, another autoimmune disease that affects the skin, but not Pemphigus vulgaris.
**Option C:** This option is incorrect because it describes a feature of bullous pemphigoid, another autoimmune disease that affects the skin, but not Pemphigus vulgaris.
**Clinical Pearl / High-Yield Fact**
Remember that the Tzank smear is a rapid diagnostic test that can be used to differentiate between Pemphigus vulgaris and other autoimmune diseases that affect the skin, such as Pemphigus foliaceus and bullous pemphigoid.
**Correct Answer: C. Acantholytic cells.**