Skin Examinations

Question 1

Define purpura

Answer 1

Extravasation of blood (leakage of blood into surrounding tissues) that does not blanche

It may or may not be raised

Question 2

Define petechia

Answer 2

1-2mm area of flat purpura

Question 3

Define erythema

Answer 3

Vascular dilation causing skin redness that blanches on pressure

Question 4

What is a macule?

Answer 4

A localised flat colour change <1cm

Question 5

What is a patch?

Answer 5

A localised flat colour change >1cm

Question 6

A macular rash is a raised/flat rash

Answer 6

Flat

Question 7

A papular rash is a raised/flat rash

Answer 7

Raised

Question 8

What is a maculopapular rash?

Answer 8

A rash with both raised and flat components

Question 9

What is a papule?

Answer 9

A localised elevated area <0.5cm

e.g., lichen planus

Question 10

What is a nodule?

Answer 10

A localised elevated area >0.5cm and with greater dermal involvement
e.g., basal cell cancer

Question 11

What is a plaque?

Answer 11

A lesion with a raised edge and a flatter surface >1cm

Question 12

Define pustule

Answer 12

A pus-filled raised lesion

e.g., herpes simplex cold sore, pustular psoriasis

Question 13

What is a vesicle?

Answer 13

A raised, fluid-filled lesion <0.5cm

Question 14

What is a bulla?

Answer 14

A raised, fluid-filled lesion >0.5cm

Question 15

What is a wheal?

Answer 15

A raised but compressible dermal swelling

e.g., skin prick testing

Question 16

What is a cyst?

Answer 16

A raised nodule containing semi-solid material

Question 17

A lesion with a pinker middle and a white ring around the outside is called a…

Answer 17

Target lesion

Question 18

What is meant by a scale?

Answer 18

A layer formed by an accumulation of fragments of keratin

Question 19

What is meant by a crust?

Answer 19

A layer formed by a dried exudate e.g., serum

e.g., cold sore

Question 20

What is meant by skin that is lichenified?

What may this be caused by?

Answer 20

Thickened with increased skin markings

This can be caused by ongoing scratching due to a chronic condition

Question 21

Define a scar

Answer 21

Normal tissue which has been replaced by fibrous tissue

Question 22

What is a fissure?

Answer 22

A linear split in the epidermis

Question 23

What is the difference between an erosion and an ulcer?

Answer 23

Erosion = superficial break in the epidermis

Ulcer = deeper break in the epidermis

Question 24

Define atrophy

Answer 24

Loss of epidermis +/- dermis

e.g., due to the use of topical steroids

Question 25

Why is skin biopsy alone not enough to come to a diagnosis? (2)

Answer 25

Some skin conditions may have the same histology e.g., different types of eczema

One cause of a skin condition may have different histological presentations e.g., drug eruption