A 60-year-old man develops painful oral erosions, haemorrhagic crusting of lips, and flexural blisters. Biopsy reveals suprabasal acantholysis with tombstone appearance. DIF shows intercellular IgG in the epidermis. Which Desmoglein pattern best explains both mucosal and skin involvement?
- A Anti-Dsg1 only
- B Anti-Dsg3 only
- C Anti-Dsg3 + anti-Dsg1 ✓
- D Anti-Dsg2 + anti-Dsg4
Correct answer: C. Anti-Dsg3 + anti-Dsg1
Explanation
In pemphigus vulgaris with mucocutaneous involvement, both anti-Dsg3 (predominant in mucosa where Dsg3 is highly expressed) and anti-Dsg1 (expressed more in superficial epidermis) antibodies are present. Dsg compensation theory: Dsg3 antibodies alone cause only mucosal disease; when both Dsg3+Dsg1 antibodies are present, skin blistering also occurs. Dsg2 is a cardiac/colonic desmosomal protein; Dsg4 is expressed in hair follicle.
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.