Lecture 1: Introduction to General Dermatology

Question 1

Answer 1

Question 2

Answer 2

Question 3

list the functions of skin

Answer 3

• thermoregulation: insulation, heat transfer
• skin immune system: innate and adaptive functions
• barrier: protects against mechanical, chemical, microorganisms, UV light, also keeps in water and electrolytes, macromolecules
• sensation
• vitamin D synthesis
• interpersonal communication

Question 4

list some external causes of skin disease

Answer 4

• temperature
• UV
• chemical (allergen or irritant)
• infection
• trauma

Question 5

list some internal causes of skin disease

Answer 5

• systemic disease
• genetics
• drugs
• infection

Question 6

what is the morphology of a macule?

Answer 6

small (usually less than 5mm), flat change in skin colour with distinct borders

Question 7

what is the morphology of a patch

Answer 7

larger, non-palpable (flat) change in skin colour with distinct borders

Question 8

what is the morphology of a papule?

Answer 8

small (less than 1 cm), palpable solid skin lesion

Question 9

what is the morphology of a plaque?

Answer 9

palpable, solid lesion greater than 1cm in diameter

Question 10

describe a vesicle?

Answer 10

fluid-containing, superficial, thin-walled cavity less than 1cm

Question 11

describe a bulla

Answer 11

fluid-containing, superficial, thin-walled cavity greater than 1cm in diameter

Question 12

describe a pustule

Answer 12

small pus filled skin lesion, superficial, thin-walled cavity

Question 13

describe an abscess

Answer 13

large, thick-walled, pus filled skin lesion

Question 14

describe an erosion

Answer 14

skin lesion with loss of epidermis only

Question 15

describe an ulcer

Answer 15

skin lesion with loss of epidermis and dermis

Question 16

describe a nodule

Answer 16

palpable, lesion more than 1cm in diameter which is taller than it is wide

Question 17

list the most common skin conditions

Answer 17

• acne
• psoriasis
• rosacea
• skin lesions
• urticaria
• warts
• leg ulcers
• scalp/nail disorders
• eczema
• infections, infestations

Question 18

what investigations are performed in dermatology if bacterial infection suspected?

Answer 18

• charcoal swab
• ask for MC&S: microscopy, culture and senitivities

Question 19

what investigations are performed in dermatology if a viral infection is suspected?

Answer 19

• viral swab for PCR
• can swab vesicle/bulla if vesicular eruption
• if systemic illness, can take throat swab

Question 20

what investigations are performed in dermatology if fungal infection suspected?

Answer 20

• skin scraping
• nail clipping
• hair sample
• fungal cultures