L7- Skin pathology

Question 1

What are melanocytic nevi?

Answer 1

• Occur on sun exposed areas - face and neck
• Remarkably round and evenly pigmented, soft on palpation
• 2-10mm

Question 2

What are the types of melanocytic nevi?

Answer 2

• Junctional between epidermis and dermis, maculopapular (flat to the touch)
• Compound in the dermis, papule (slightly raised to the touch)
• Intradermal- all melanocytes have dropped down into the dermis and have matured, nodule (proudly raised)

Question 3

What are malignant melanomas?

Answer 3

• Benign is when melanocytes mature and drop down into the dermis layer
• Malignant stay in the upper layers
• Asymmetrical with uneven borders and colouring
• Larger than 2.5 inches

Question 4

What is pleomorphism?

Answer 4

Variability in the size and the shape of cells

Question 5

What are the types of inflammatory dermatoses?

Answer 5

• Spongiotastic- epidermis soaks up oedema, eczema
• Psoriasiform- scaly pattern, psoriasis
• Interface/lichenoid- attacks junction
• Bullous- causes blisters

Question 6

What do eczema and psoriasis affect?

Answer 6

Eczema affects flexor areas (folds of elbow and knee)

Psoriasis affects extensor areas (surfaces of elbow and knee)

Question 7

What is lupus erythematosus?

Answer 7

• Butterfly rash, raised, attacks junction and basal keratinocytes so healing occurs with lots of scarring