Student Memory Support
Topic 10 — Noninfectious Skin Disorders and Generalized Rash
Final Year MBBS • Dermatology • High-yield memory reinforcement and last-minute revision
1. High-Yield Flashcards
Tap each question to reveal the answer.
Flashcard 1 — Q: What four major processes contribute to acne vulgaris?
A: Increased sebum, follicular hyperkeratinization, Cutibacterium involvement and inflammation.
Flashcard 2 — Q: Which acne lesions indicate follicular plugging?
A: Open and closed comedones.
Flashcard 3 — Q: What is the classic morphology of acute eczema?
A: Pruritic erythema with vesiculation, weeping and crusting.
Flashcard 4 — Q: What does repeated scratching produce in chronic eczema?
A: Lichenification with thickened skin and accentuated skin markings.
Flashcard 5 — Q: What is the typical appearance of chronic plaque psoriasis?
A: Well-demarcated erythematous plaques with silvery scale, commonly on extensor surfaces.
Flashcard 6 — Q: Which additional sites should be checked in a patient with psoriasis?
A: Scalp, nails and joints.
Flashcard 7 — Q: What is the classic morphology of lichen planus?
A: Pruritic, purple, polygonal, flat-topped papules, often with Wickham striae.
Flashcard 8 — Q: Where is seborrheic dermatitis commonly found?
A: Scalp, eyebrows and nasolabial folds, usually with greasy scaling.
Flashcard 9 — Q: What is the characteristic lesion of urticaria?
A: A transient pruritic wheal caused by superficial dermal edema.
Flashcard 10 — Q: What distinguishes angioedema from an ordinary urticarial wheal?
A: Angioedema involves deeper dermal and subcutaneous tissues.
Flashcard 11 — Q: What are the typical lesions of erythema nodosum?
A: Tender erythematous subcutaneous nodules, classically over the shins.
Flashcard 12 — Q: What blister pattern suggests pemphigus vulgaris?
A: Fragile flaccid bullae with painful mucosal erosions due to intraepidermal acantholysis.
Flashcard 13 — Q: What blister pattern suggests bullous pemphigoid?
A: Pruritic tense bullae caused by subepidermal separation.
Flashcard 14 — Q: Which drug eruption repeatedly recurs at the same site?
A: Fixed drug eruption, often leaving residual pigmentation.
Flashcard 15 — Q: Which features in a drug rash suggest a severe cutaneous adverse reaction?
A: Skin pain, mucosal erosions, blistering or epidermal detachment with systemic illness.
Flashcard 16 — Q: Why can erythroderma become systemically dangerous?
A: Extensive skin-barrier dysfunction can cause fluid and protein loss, temperature dysregulation and infection risk.
2. Mnemonics
3. Memory Tables
Pemphigus Vulgaris vs Bullous Pemphigoid
| Feature | Pemphigus Vulgaris | Bullous Pemphigoid |
|---|---|---|
| Blister level | Intraepidermal | Subepidermal |
| Blister | Flaccid / fragile | Tense |
| Mucosa | Commonly involved | Less prominent |
| Immunopathology | Intercellular IgG | Linear basement-membrane deposition |
Common Inflammatory Dermatoses
| Condition | Memory Clue | Typical Distribution |
|---|---|---|
| Psoriasis | Well-demarcated silvery plaques | Extensor surfaces / scalp |
| Lichen planus | Purple polygonal pruritic papules | Wrists / ankles / oral mucosa |
| Seborrheic dermatitis | Greasy scale | Scalp / eyebrows / nasolabial folds |
| Eczema | Itch with acute ooze or chronic lichenification | Depends on eczema subtype |
4. Rapid Revision Points — Last-Minute Revision
- Generalized rash assessment = morphology + distribution + mucosa + palms/soles + systemic clues.
- Acne affects the pilosebaceous unit and may progress from comedones to inflammatory and nodular lesions.
- Acute eczema tends to vesiculate and ooze; chronic eczema tends to lichenify.
- Psoriasis may involve skin, scalp, nails and joints.
- Lichen planus: purple polygonal pruritic papules with possible Wickham striae.
- Seborrheic dermatitis favors sebaceous areas and is associated with Malassezia.
- A wheal is superficial edema; angioedema is deeper tissue edema.
- Erythema nodosum should trigger a search for an underlying systemic association guided by history.
- Flaccid blister + mucosal erosion favors pemphigus; tense pruritic blister favors pemphigoid.
- Skin pain, mucosal injury or epidermal detachment after a drug is a major warning sign for a severe cutaneous reaction.
5. Clinical Memory Hooks
6. Starred High-Yield Exam Points
- ⭐ Acne pathogenesis: sebum + follicular hyperkeratinization + Cutibacterium contribution + inflammation.
- ⭐ Psoriasis: well-demarcated erythematous plaques with silvery scale; assess nails and joints.
- ⭐ Urticaria produces transient wheals; airway or circulatory compromise indicates anaphylaxis.
- ⭐ Pemphigus vulgaris: flaccid bullae, mucosal involvement and intercellular IgG deposition.
- ⭐ Bullous pemphigoid: tense bullae with subepidermal separation and linear basement-membrane immunoreactants.
- ⭐ Fixed drug eruption recurs at the same site and may leave residual pigmentation.
- ⭐ SJS/TEN warning pattern: drug exposure + skin pain + mucosal erosions + epidermal detachment.