FCPS IMM Medicine Dermatology MCQs: High-Yield Practice Questions & Prep

Dermatology is a smaller block in the IMM Medicine paper — 42 questions in HighYield's bank — but it's the one subject in this series that hasn't had a dedicated practice post until now. Vignettes lean on pattern recognition: a description of a rash or lesion, and a diagnosis to match. Below is a sample set in the same style you'll see on exam day, with the reasoning after each answer.

Sample Dermatology MCQs

1. A patient on a newly started antiepileptic develops target-shaped lesions, mucosal erosions, and epidermal detachment over 35% of the body surface area. What is the diagnosis?

• A) Stevens-Johnson syndrome
• B) Toxic epidermal necrolysis (TEN) ✅
• C) Erythema multiforme
• D) Urticaria

Why: SJS and TEN are a spectrum defined by the percentage of epidermal detachment — SJS is under 10%, TEN is over 30%, and 10–30% is classed as overlap.

2. A pearly papule with telangiectasia on sun-exposed skin is the classic presentation of which skin cancer, the most common of all?

• A) Squamous cell carcinoma
• B) Basal cell carcinoma ✅
• C) Malignant melanoma
• D) Kaposi sarcoma

Why: Basal cell carcinoma is the most common skin malignancy and typically presents as a slow-growing, pearly, telangiectatic papule or nodule on chronically sun-exposed skin.

3. Asymmetry, Border irregularity, Color variation, Diameter over 6mm, and Evolution (ABCDE) are screening criteria for which lesion?

• A) Seborrheic keratosis
• B) Actinic keratosis
• C) Malignant melanoma ✅
• D) Basal cell carcinoma

Why: The ABCDE rule flags features suspicious for melanoma on a pigmented lesion and prompts biopsy rather than reassurance.

4. A sharply demarcated, raised, tender, erythematous plaque on the face, involving the upper dermis and superficial lymphatics and caused by Streptococcus, describes:

• A) Cellulitis
• B) Erysipelas ✅
• C) Necrotizing fasciitis
• D) Impetigo

Why: Erysipelas is more superficial than cellulitis, which is why its border is sharply demarcated; cellulitis involves the deeper dermis and subcutaneous tissue and spreads with a less distinct edge.

5. Silvery scale on well-demarcated erythematous plaques over extensor surfaces, with pinpoint bleeding when scale is removed, describes which sign and condition?

• A) Nikolsky sign; pemphigus
• B) Auspitz sign; psoriasis ✅
• C) Darier sign; mastocytosis
• D) Koebner phenomenon alone; lichen planus

Why: The Auspitz sign — pinpoint bleeding after scale removal — reflects the thinned suprapapillary epidermis over elongated dermal papillae characteristic of psoriasis.

6. Intense itching that worsens at night, with burrows in the finger webs, wrists, and genital area, is caused by a mite in which condition?

• A) Pediculosis
• B) Scabies ✅
• C) Tinea corporis
• D) Allergic contact dermatitis

Why: Scabies is caused by Sarcoptes scabiei burrowing into the stratum corneum, with nocturnal itching from a delayed hypersensitivity reaction to the mite and its products.

7. Tender erythematous nodules on the anterior shins, often associated with sarcoidosis, streptococcal infection, or inflammatory bowel disease, describe:

• A) Erythema nodosum ✅
• B) Pyoderma gangrenosum
• C) Granuloma annulare
• D) Erythema multiforme

Why: Erythema nodosum is a panniculitis (inflammation of subcutaneous fat) typically on the shins, and is a recognised reactive marker of several systemic conditions rather than a disease in its own right.

8. Acute urticaria with angioedema that has anaphylactic features is treated first with:

• A) Oral antihistamines alone
• B) Intramuscular epinephrine, with antihistamines and steroids as adjuncts ✅
• C) Topical corticosteroids
• D) Oral antibiotics

Why: Epinephrine reverses the airway and haemodynamic threat in anaphylaxis directly; antihistamines and steroids help symptoms but act too slowly to be first-line alone.

How to Approach Dermatology for IMM

• Pattern-match the clinical description to the named sign or condition — most dermatology vignettes are answerable from the description alone, without needing a photograph.
• Learn paired look-alikes together (SJS vs TEN, erysipelas vs cellulitis) since examiners frequently test the distinguishing feature, not the disease in isolation.
• Know the first-line emergency step for anaphylaxis cold — it's a frequent standalone question across IMM, not just dermatology.

These questions come from HighYield's FCPS IMM Medicine QBank, which holds over 2,400 clinical-vignette MCQs with an explanation for every answer. The first 20 questions are free in Tutor mode, so you can judge the explanation quality before unlocking the full bank.