pathology

Last reviewed 01/2018

Pemphigus is characterized by intra-epidermal separation of keratinocytes forming a split between the upper and lower portions of the epidermis, and acantholysis - separation of individual keratinocytes which float freely in the blister.

Seperation of the keratinocytes occurs when autoantibodies directed against desmogleins (a protein which modulates adhesion within desmosomes) binds to the surface of keratinocytes and causes loss of cell adhesion properties (1).

Autoantibodies, usually IgG, may be found between cells throughout the epidermis and in the patient's serum. Titres correlate with disease activity (1).

In Pemphigus vulgaris, the base of the blister is formed by the basal cells of the epidermis (1). Other varieties have more superficial blisters with splitting sometimes not occuring until the stratum corneum (e.g. - in pemphigus foliaceus) (1).

In Pemphigus vegetans, there may be a large number of eosinophils around the blister base.

Reference:

• 1. Stanley J.R, Amagai M. Pemphigus, Bullous Impetigo, and the Staphylococcal Scalded-Skin Syndrome. NEJM 2006; 355:1800-1810