A 50 year old male known case of myasthe-nia with erythemated shallow erosions with few blisters and scales. Oral mucosa is not involved. Immunopathology demonstrates IgG deposition on keratinocytes and auto antibodies against Dsg -1. The diagnosis is

C i.e. Pemphigus foliaceus Pemphigus foliaceous (PF) is distinguished from PV by following features? Distribution of lesion in both is much the same (i.e. seborrheic distribution including face, scalp and upper trunk) except that in PF the mucous membranes are almost always sparedQ. - Characteristic clinical lesions of PF are well demarcated, shallow erosions on an erythematous base with scales, crust formation, erythemaQ and sometimes surrounded with small vesicles along the borders. Patients often complain of both pain & burning in the leions. Eventually patient becomes erythrodermic with crusted, oozing & red skin. Sun exposure (UV rays), environmental stimuli (insect bites), auto immune diseases paicularly thymoma &/or myasthenia gravisQ, and drug exposure (eg drug containing thiol group like penicillamine, captopril, enalapril and non thiol drugs like penicillins, cephalosporins and piroxicams) may be associated and aggrevating factor. PF is generally less severe and carries better prognosis than PV. Histology (tzank smear) shows superficial acantholytic blisters just below stratum corneum and in granular layer. And DIM demonstrates autoantibodies against Dsg1Q. Because of lack of mucosal involvement autoantibodies against Dsg3 are not foundQ. Because of superifical cleavage, the small flaccid blisters rupture easily and PF rarely demonstrate intact blisters.