5. Epidemiology :
- Equal Incidence rate in both genders .
- Most patient presenting during the 4th and 5th
decades of life .
- Genetic and ethnic factors: Ashkenazic Jews
and Mediterranean patients .
6. Clinical features :
- Painful ulcers .
- Intra oral: Bullae apprear on any part of oral
mucosa and becomes ulcers, fig (1-2) .
- Extra oral : blisters appear on skin of face, back
or chest, fig(3) .
- Positive Nikolsky`s sign .