In pemphigus foliaceus, the histological split occurs at the level of the granular layer, unlike pemphigus vulgaris (suprabasal split). This is because the autoantibody in PF targets:

• A Desmoglein-3
• B Desmoplakin
• C BP230
• D Desmoglein-1 ✓

Explanation

Pemphigus foliaceus is caused by IgG autoantibodies against desmoglein-1 (DSG1), which is predominantly expressed in the upper epidermis (granular and spinous layers). Since DSG3 (targeted in PV) is expressed throughout the epidermis and compensates in the lower layers, DSG1-only autoimmunity causes superficial cleavage. Pemphigus vulgaris autoantibodies target DSG3 (primarily) causing suprabasal split; mucocutaneous PV involves both DSG3 and DSG1. Desmoplakin mutations cause striate palmoplantar keratoderma; BP230 is targeted in bullous pemphigoid.

Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.