- Definition: Epidermis sloughs off with gentle lateral pressure.
- Mechanism: Loss of cell-to-cell adhesion (acantholysis) within the epidermis or loss of adhesion at the dermoepidermal junction.
- Associated Conditions (Nikolsky Positive)
- Pemphigus Vulgaris: Autoantibodies vs. desmogleins. Flaccid bullae.
- Toxic Epidermal Necrolysis (TEN): Severe drug reaction.
- Staphylococcal Scalded Skin Syndrome (SSSS): Exfoliative toxin cleaves desmoglein-1.
- Key Negative Association
- Bullous Pemphigoid: Nikolsky is negative. Autoantibodies vs. hemidesmosomes. Tense bullae.
- The entire epidermis remains intact, resulting in tense bullae that do not rupture easily with pressure.