Erosions and ulcers with crusting and exudation are therefore the common signs. Cytology of exudate may be helpful diagnostically as it may reveal the rounded acantholytic keratinocytes typical of the disease, and immunofluorescence can be used to demonstrate the deposition of antibodies in the lesions. | Erosions and ulcers with crusting and exudation are therefore the common signs. Cytology of exudate may be helpful diagnostically as it may reveal the rounded acantholytic keratinocytes typical of the disease, and immunofluorescence can be used to demonstrate the deposition of antibodies in the lesions. |