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What is Tzank smear in a case of pemphigus vulgaris show and explain in detail?
Cytodiagnosis is of most value in pemphigus and its various forms. Acantholysis is the loss of intercellular connections, such as desmosomes, resulting in loss of cohesion between keratinocytes, seen in diseases such as pemphigus vulgaris. It is absent in bullous pemphigoid, making it useful for differential diagnosis In bulbous pemphigoid, eosinophils are commonly seen. Ref Harrison 20th edition pg 1245