Skin Flashcards Preview

Dermatology > Skin > Flashcards

Flashcards in Skin Deck (57)
Loading flashcards...
1

What is the layers of the skin (biggest organ of the body)

Epidermis
Dermis
Hypodermis = subcutaneous tissue which anchos skin to fascia (useful in insulation)

Skin appendages = derived from skin cells
- Hair
- Nails
- Sebaceous glands
- Sweat glands

2

What is the epidermis made up of and what pathology can affect

Striatum cornea (thick top layer made up of keratin)
- Thickest in palms and soles
- Thin at eyelids
Keratonocytes - produce keratin
Melanocytes - produce melanin
Lagerhan's - immune (process antigen and migrate to LN)
Average turnover = 30 days

Pathology
- Change in turnover e.g. psoriasis
- Change in surface or loss of epidermis e.g. scales / ulcer
- Change in pigmentation

3

What is the dermis made up of

Collagen = mainly
Fibroblasts synthesis elastin
Dendiritc cells for immune
Nerves + blood vessels
Adrenal structures - hair / glands / sensory

Pathology
- Change in contour / loss of dermis
- Disorder of skin appendages - hair / acne (Sebaceous gland)
- Change lymphatics / blood vessel - erythema, urticaria, purpura

4

What are nails made up of

Nail plate (hard keratin) which arises from nail matrix at posterior nail fold and rests on nail bed
Nail bed contains capillaries which give colour

5

What is the stages of the hair cycle and types of hair

Lanugo - fine long hair in fetus
Vellus - fine short hair on all areas
Terminal - coarse long hair on scalp, eyebrows, eyelash and pubic

Hair shaft - keratinised tube
Hair bulb - actively dividing cells and melanocyte which gives pigment

Anagen = active growing
Catagen = growth stops + follicle shrinks
Telogen = resting phase

6

What are the functions of the skin

Thermoregulation - insulation / sweat / blood flow
Immune system - innate and adaptive
Barrier
Sensation
Synthesis of Vitamin D
Personal communication

7

What causes skin disease

Photosensitivity - often medication
Temperature - frost bite / necrosis / cold urticaria
Trauma - dermatitis artefacts
Genetics - eczema / psoriasis / acne / neurofibroma
Autoimmune - bullous pemphigoid
Infection
Systemic

8

What is a macule

Small flat circumscribed area <5mm of altered colour

9

What is a patch

Larger flat area of altered colour >5mm

10

What is a papule

Small raised area <0.5cm

11

What is a plaque

Large raised area >0.5cm

12

What is a vesicle

Small fluid filled lesion <0.5cm

13

What is a bullae

Large fluid filled

14

What is a pustule

Small pus

15

What is an abscess

Large pus in dermis or subcutaneous tissue

16

What is wheal

Transient raised lesion due to localised oedema

17

What is an erosion

Superficial loss of epidermis
Heals without scarring

18

What is an ulcer

Loss of epidermis and denims
Heals with scarring

19

Why can skin regenerate

Has stem cells

20

What causes purpura in children

Thrombocyotpenia
Meningococcal septicaemia - non-palpable
ALL
Congenital bleeding disorder
ITP
HSP - tend to be palpable
NAI

21

What should you do to all children with new onset purpuric rash

Always admit to exclude life threatening
Ax prior to transfer to hospital as may be due to menigococcal septicaemia
Clotting screen and platelet to exclude coagulation disorder

22

What causes purpura in adults

Vasculitis
Bone marrow failure
ITP
Drugs
Nutrition

23

What can distribution of skin disease be

Localised
Generalised
Symmetrical

24

How can you investigate skin disease

Charcoal swab - bacterial and fungal
Viral swab - vesicular eruption
Skin scraping
Nail scraping
Dermoscopy

25

What do you send swab for

MC+S if charcoal
PCR if viral
Biopsy

26

Do you swab in cellulitis

No as will have pyrexia so need blood culture

27

What do you do if fungal suspect

Skin scraping
Nail clipping
Hair sample
Fungal culture

28

What is important in HPC of skin problem

Duration
Initial appearance and evolution
Symptoms - itch / pain
Aggravating and relieving factors
Previous and current Rx
Recent contact / stress / travel
Hx sunburn or sunbeds
Skin type

29

What else is important

PMH - atopy / skin cancer
FH - skin disease
SH - occupation / do skin lesions improve
DH
QOL

30

How do you examine skin lesion

Inspect
Describe
Palpate
Systematic check