Skin Anatomy
Epidermal Layers (Superficial to Deep)
| Layer | Key Characteristic |
|---|---|
| Stratum Corneum | Dead, anucleated cells (keratin). |
| Stratum Lucidum | Present ONLY in thick skin (palms/soles). |
| Stratum Granulosum | Keratohyalin granules. |
| Stratum Spinosum | Desmosomes (intercellular bridges); Langerhans cells. |
| Stratum Basale | Stem cells; site of melanocytes and Merkel cells. |
NEET PG “Must-Know” Clinical Pearls
- Pemphigus Vulgaris: Autoantibodies against desmoglein (desmosomes); causes flaccid bullae, Nikolsky sign positive (intraepidermal).
- Bullous Pemphigoid: Autoantibodies against hemidesmosomes (basement membrane); causes tense bullae (subepidermal).
- Thick vs. Thin Skin: Thick skin has a stratum lucidum and lacks hair follicles/sebaceous glands.
- Dermatitis Herpetiformis: Strongly associated with Celiac disease (IgA deposits at dermal papillae).