Introduction to Dermatology

Question 1

What is the largest organ in the body?

Answer 1

Skin

Question 2

What are some skin adnexal structures?

Answer 2

Hair

Nails

Glands

Sensory structures

Question 3

What are important functions of the skin?

Answer 3

• Protection
• Homeostasis
• Transmission of sensation

Question 4

What are the layers of the skin from superficial to deep?

Answer 4

Epidermis

Dermis

(then below but not part of the skin is the hypodermis)

Question 5

What are the layers of the skin from superficial to deep (invidividual layers)?

Answer 5

Stratum corneum

Stratum lucidum

Stratum granulosum

Stratum spinosum

Stratum basale

Question 6

What forms the stratum corneum?

Answer 6

Dead cells with a hard protein envelope

Cells contain keratin and are surrounded by lipids

Question 7

What forms the stratum lucidum?

Answer 7

Dead cells lie within despersed keratohyalin

Question 8

What forms the stratum granulosum?

Answer 8

Keratohyalin and a hard protein envolope

Lamellar bodies release lipids

Cells die

Question 9

What forms the stratum spinosum?

Answer 9

Keratin fibres and lamellar bodies accumulate

Question 10

What forms the stratum basale?

Answer 10

Cells divide by mitosis and some of the newly formed cells become the cells of the more superficial streta

Question 11

What within the skin releases lipids?

Answer 11

Lamellar bodies

Question 12

What is A?

Answer 12

Question 13

What are the 3 different stages of the hair cycle?

Answer 13

Anagen

Catagen

Telogen

Question 14

What is the anagen phase of hair cycle?

Answer 14

Active growing phase

Question 15

What is the catagen phase of hair cycle?

Answer 15

2-3 week phase growth stops/follicles shrink

Question 16

What is the telogen phase of hair cycle?

Answer 16

Resting phase for 1-4 months

Question 17

How long does the telogen phase of hair cycle last?

Answer 17

1-4 months

Question 18

How long does the catagen phase of hair growth last?

Answer 18

2-3 weeks

Question 19

During what phase of the hair cycle is most hair in?

Answer 19

Anagen (80-90% hair)

Telogen (up to 10% of hair)

Categen (1-3% of hair)

Question 20

What are some functions of the skin?

Answer 20

• Thermoregulation
  
  • Insulation, heat transfer
• Skin immune system
  
  • Innate and adaptive functions
• Barrier
  
  • Protects against mechanical, chemical, microorganisms, UV light
  • Keep in water and electrolytes, macromolecules
• Sensation
  
  • Temperature, touch and pain
• Vitamin D synthesis
  
  • UV light converts 7-dehydrocholesterol to cholecalciferol
• Interpersonal communication
  
  • Physical appearance, smell, self-identity

Question 21

The skin acts as a barrier to protect against what?

Answer 21

Mechanical, chemical, microorgasms and UV light

Question 22

What kinds of sensations does the skin transmit?

Answer 22

Temperature

Touch

Pain

Question 23

How does the skin perform vitamin D synthesis?

Answer 23

UV light converts 7-dehydrocholesterol to cholecalciferol

Question 24

How much of skin disease is skin cancer/lesions?

Answer 24

50%

Question 25

Why is skin disease important?

Answer 25

* Disfigurement * Discomfort * Disability * Depression * Death

Question 26

What are some causes of skin disease?

Answer 26

* External * Temperature * Cold injury * Frostbite, chilblains * Skin necrosis * Cold urticaria * UV * Called photosensitivity * Commonly caused by medications * Exposed sites affected * Can be sensitive to UVA, UVB, visible light or a combination * Chemical * Infection (allergen or irritant) * Trauma * Dermatitis artefacta (skin lesions solely produced by patients own actions) * Internal * Systemic disease * Genetics * Drugs * Think of OTC drugs * Infection * Autoimmune * Bullous pemphigoid

Question 27

What can cold injuries to the skin cause?

Answer 27

Frostbite, chilblains Skin necrosis Cold urticaria

Question 28

What are chilblains?

Answer 28

Small lesions caused by inflammation of small blood vessels due to exposure to cold air

Question 29

What is cold urticaria?

Answer 29

Disorder where hives (urticaria) or large red welts form on the skin after exposure to a cold stimulus

Question 30

What is a skin lesion solely produced by patients own actions called?

Answer 30

Dermatitis artefacta

Question 31

What is an example of an autoimmune skin disease?

Answer 31

Bullous pemphigoid

Question 32

What is the morphology of a skin lesion?

Answer 32

Appearance of a skin lesion

Question 33

How big is a "small" skin lesion?

Answer 33

Typically means less than 5mm

Question 34

What are some descriptive words for skin lesions?

Answer 34

* Macule * Small circumscribed area * Patch * Larger circumscribed area * Papule * Small raised area * Plaque * Larger raised area * Vesicle * Small fluid filled * Bulla * Large fluid filled * Pustule * Small pus filled * Abscess * Large pus filled * Erosion * Loss of epidermis * Ulcer * Loss of epidermis and dermis

Question 35

What is a macule?

Answer 35

Small circumscribed area

Question 36

What is a patch?

Answer 36

Larger circumscribed area

Question 37

What is a papule?

Answer 37

Small raised area

Question 38

What is a plaque?

Answer 38

Larger raised area

Question 39

What is a vesicle?

Answer 39

Small fluid filled lesion

Question 40

What is a bulla?

Answer 40

Large fluid filled lesion

Question 41

What is a pustule?

Answer 41

Small pus filled lesion

Question 42

What is an abscess?

Answer 42

Large pus filled lesion

Question 43

What is an erosion?

Answer 43

Loss of epidermis

Question 44

What is an ulcer?

Answer 44

Loss of epidermis and dermis

Question 45

What is a lesion?

Answer 45

A region in an organ or tissue which has suffered damage through injury or disease

Question 46

What does distribution of a lesion refer to?

Answer 46

How skin lesions are scattered or spread out

Question 47

What are the different kinds of distributions of lesions?

Answer 47

Isolated or multiple

Question 48

What is used to describe skin lesions?

Answer 48

Morphology Distribution

Question 49

What are some examples of common skin conditions?

Answer 49

Question 50

What are some examples of general conditions that can have cutaneous signs?

Answer 50

* Erythema nodosum * Sarcoidosis * Vasculitis * Malignancy * Auto-immune conditions

Question 51

What does cutaneous mean?

Answer 51

Relating to or affecting the skin

Question 52

What is a skin sign of hyperlipidaemia?

Answer 52

Eruptive xanthoma

Question 53

What is acanthosis nigricans?

Answer 53

Brown to black, poorly defined, velvety hyperpigmentation of the skin Hyperkeratosis and hyperpigmentation

Question 54

What is acanthosis nigricans associated with?

Answer 54

insulin resistance

Question 55

What investigations should be done if bacterial infection is suspected for a skin condition?

Answer 55

* Charcoal swab * Ask for MC&S * Microscopy * Culture * Sensitivities

Question 56

What investigations should be done if viral infection is suspected for a skin condition?

Answer 56

* Viral swab for PCR * Can swab vesicle/bulla if vesicular eruption * If systemic illness, can take throat swab

Question 57

What investigations should be done if bacterial infection is suspected for a skin condition?

Answer 57

* Skin scraping * Nail clipping * Hair sample * Fungal cultures

Question 58

What is a simple way to take a skin biopsy?

Answer 58

Punch biopsy

Question 59

What is B?

Answer 59

Question 60

What is C?

Answer 60

Question 61

What is D?

Answer 61

Question 62

What is E?

Answer 62

Question 63

What is B?

Answer 63

Question 64

What is C?

Answer 64

Question 65

What is H?

Answer 65

Question 66

What is I?

Answer 66

Question 67

What is J?

Answer 67

Hyponychium