Skin

Question 1

Macule

Answer 1

A circumscribed, non-palpable spot characterised by a change in the colour of the skin. A larger lesion >1.0cm is a patch.

Question 2

Papule

Answer 2

A small solid elevation of the skin <1.0cm diameter

Question 3

Plaque

Answer 3

A large (>1.0cm) flat-topped elevation formed by extension or coalescence of papules

Question 4

Nodule

Answer 4

A circumscribed solid elevation that is > 1.0cm diameter. Usually due to massive cell infiltration that may be inflammatory or neoplastic.

Question 5

Tumour

Answer 5

A mass of ≥ 2.0cms that, strictly speaking may be neoplastic or non-neoplastic (e.g. granulomatous). Term often used to imply neoplasm.

Question 6

Pustule

Answer 6

May be intraepidermal, subepidermal or follicular. Typically contain neutrophils and bacteria but may contain eosinophils and/or be sterile
Often transient

Question 7

Abcess

Answer 7

A localised collection of pus in an area of tissue destruction surrounded by inflammation; usually more deeply located than a pustule

Question 8

Vesicle or Bulla

Answer 8

Sharply circumscribed epidermal elevation filled with clear fluid. May be intraepidermal or subepidermal. A bulla is similar but >1.0cm diameter.

Question 9

Wheal (hive)

Answer 9

A circumscribed raised lesion due to oedema, often transient. Angiooedema is similar but deeper and more extensive.

Question 10

Cyst

Answer 10

An epithelium-lined cavity containing fluid or solid (inspissated) material. Smooth, well circumscribed, usually fluctuant.

Question 11

Collarette

Answer 11

A circular rim of scale (loose or peeling keratin) that evolves from a pustule, vesicle or bulla

Question 12

Excoriation

Answer 12

Erosions or ulcers caused by self trauma i.e. scratching, rubbing or biting. Typically linear in configuration they generally indicate pruritus.

Question 13

Erosion

Answer 13

A shallow epidermal defect that does not penetrate the basement membrane and thus heals by regeneration i.e. without scarring.

Question 14

Ulcer

Answer 14

An epidermal defect with exposure of the underlying dermis. It results from a deep pathological process and heals by repair (scarring).

Question 15

Fissure

Answer 15

A linear cleavage of epidermis +/- dermis due to disease or injury that appears as a sharply defined cleft or multiple small cracks.

Question 16

Scar

Answer 16

Connective tissue repair of dermal injury results in fibrous tissue that replaces normal skin components

Question 17

Lichenification

Answer 17

Thickening and hardening of the skin produces exaggerated skin markings. Typically due to friction; areas may be hyperpigmented.

Question 18

Callus

Answer 18

A localised area of rough, thickened, hyperkeratotic skin forming an alopecic, and often lichenified, plaque. Due to long term friction.

Question 19

Scale

Answer 19

An accumulation of keratinised cells. (Normal loss of cornified cells is not visible to the naked eye.) Scale may be thin, thick, dry or oily.

Question 20

Crust

Answer 20

Crust is formed from dried exudate that adheres to the skin surface. It consists of any combination of serum, blood, cells or scales.

Question 21

Comedo

Answer 21

• A plug of cornified cells and sebaceous material within the dilated lumen of a hair follicle. Follicular casts are ‘microcomedones’.
• Follicle that is plugged and distended by cells.
• Follicle is intact but distended to hold blood

Question 22

Follicular Cast

Answer 22

An accumulation of keratinous debris that adheres to the hair shaft and protrudes from the follicle ostium.

Question 23

Primary or secondary lesions

Answer 23

Alopecia (hair loss)
Scale
Crust
Follicular Casts
Comedo
Pigment alteration

Question 24

Secondary lesions

Answer 24

Epidermal collarette
Excoriation
Erosion or Ulcer
Fissure
Scar 
Lichenification
Callus

Question 25

Primary lesions

Answer 25

Macule or (>1cm) Patch
Papule or (>1cm) Plaque
Vesicle or (>1cm) Bulla
Pustule (or Abscess)
Wheal (or Angioedema) 
Cyst
Nodule (1-2cm); Tumour (>2cm)