Equine Dermatology

Question 1

Categories

Answer 1

• 1). Scaling + crusting - most common
• 2). Lumps + bumps: papules, nodules, mass
• 3). Pruritus/pain: skin trauma, rubbing, 2y hair loss from trauma
• 4). Hair loss/changes in hair quality: 1y hair loss, skin fine
• 5). Moist + exudative: uncommon
• 6). Pigmentary changes: depigmentation most common
• 7). Skin disease as part of a wider systemic disorder

Question 2

Answer 2

Insect bite hypersensitivity = Sweet itch, from Culicoides midge

Question 3

When are allergies seen?

Answer 3

• Not in foals
• > 5/6 y/o
• Sweet itch = > 2 y/o

Question 4

Answer 4

Papilloma - seen in young foals and yearlings due to limited immune response

Question 5

Where are sarcoids common

Answer 5

• Older horses

Question 6

Answer 6

Dermatophytosis

Question 7

Answer 7

• Pastern dermatitis (mud fever) - triggered by persistent wetting of lower limbs
• Skin irritation -> 2y infection
• May be seen in other horses

Question 8

Answer 8

Insect bite hypersensitivity

Question 9

Answer 9

• HERDA = genetic disease in quarter horses and appaloosas, especially cutting horses
• Stretchy skin, severe skin wounds and scarring along the back and withers
• Not that important

Question 10

Answer 10

Flat sarcoid

Question 11

Answer 11

Previous Tx making skin lesion worse

Question 12

Macule/patch

Answer 12

• Flat lesion = change in pigmentation, depigmentation usually
• E.g. Vitiligo, post-inflammatory leucoderma, erythema multiforme

Question 13

Answer 13

Vitiligo

Question 14

Answer 14

Post-inflam leucoderma

Question 15

Answer 15

Erythema multiforme

Question 16

Papule

Answer 16

• Small raised lesion
• < 1 cm
• Usually infective - bacterial or fungal
• Can be allergic but would present as larger wheals
• E.g. Dermatophytosis
• Staphyloccocal folliculitis or both

Question 17

Answer 17

Dermatophytosis

Question 18

Answer 18

Staphylococcal folliculitis

Question 19

Answer 19

Dermatophytosis + staphyloccocal folliculitis

Question 20

Nodule/mass

Answer 20

Question 21

Answer 21

Eosinophilic granulomas

Question 22

Answer 22

Sarcoid

Question 23

Answer 23

Melanoma

Question 24

Answer 24

Botriomycosis - draught breeds prone to chronic progressive lymphoedema -> fill w/ fluid -> irritation from feather lice scratch

Question 25

Plaque/wheal

Answer 25

Question 26

Answer 26

Urticaria

Question 27

Answer 27

Lymphoma

Question 28

Answer 28

Urticaria - hives allergic skin reaction

Question 29

Vesicle/bulla/pustule

Answer 29

Question 30

Answer 30

Pemphigus foliaceus = autoimmune pustules/crusts

Question 31

Alopecia/hypotrichosis

Answer 31

Question 32

Answer 32

Telogen defluxion - excessive hair shedding, been sick recently

Question 33

Answer 33

Lice

Question 34

Answer 34

Pemphigus foliaceus

Question 35

Answer 35

Alopecia areta - immune attack on hair follicles

Question 36

Answer 36

Sarcoid

Question 37

Answer 37

Dermatophytosis

Question 38

Hyperkeratosis/lichenification

Answer 38

Question 39

Answer 39

Linear keratosis

Question 40

Answer 40

Aural plaque (papilloma)

Question 41

Answer 41

Insect bite hypersensitivity

Question 42

Scale

Answer 42

Question 43

Answer 43

Seborrhoea

Question 44

Answer 44

Pemphigus foliaceus

Question 45

Answer 45

Chorioptes

Question 46

Answer 46

Sarcoidosis -> granulomatous chronic skin disease

Question 47

Crust

Answer 47

Question 48

Answer 48

Pastern dermatitis

Question 49

Answer 49

Dermatophytosis

Question 50

Answer 50

Cutaneous lupus

Question 51

Answer 51

Pemphigus foliaceus

Question 52

Ulcer/erosion

Answer 52

Question 53

Answer 53

Staphylococcal dermatitis

Question 54

Answer 54

Candidiasis

Question 55

Answer 55

Chemical burn

Question 56

Answer 56

Abrasion

Question 57

Answer 57

Photoaggravated vasculitis

Question 58

Answer 58

Intertrigo

Question 59

Mixed lesion

Answer 59

Question 60

Mucocutaneous

Answer 60

Question 61

Answer 61

EHV-3

Question 62

Answer 62

Rhinosporidium - fungal

Question 63

Answer 63

Abrasive diet

Question 64

Answer 64

Contact irritant

Question 65

Answer 65

Abrasive diet

Question 66

Answer 66

Cutaneous lupus

Question 67

Limb distribution

Answer 67

Question 68

Answer 68

Chorioptic mange

Question 69

Answer 69

Cannon keratosis

Question 70

Answer 70

Lymphoedema

Question 71

Answer 71

Photoaggravated vasculitis

Question 72

Answer 72

• “Mallenders amd Sallenders”
• Common in cobs + draught breeds
• Back of carpi, front of tarsi

Question 73

Dorsal distribution

Answer 73

Question 74

Answer 74

Herda

Question 75

Answer 75

Dermatophytosis

Question 76

Answer 76

Dermoid cysts = directly in midline

Question 77

Answer 77

Eosinophilic granuloma = off to side of midline (DDx = dermoid cysts)

Question 78

Facial distribution

Answer 78

Question 79

Answer 79

Papilloma

Question 80

Answer 80

Sarcoid

Question 81

Answer 81

Dermatophyte

Question 82

Answer 82

Papilloma

Question 83

Answer 83

Pemphigus foliaceus

Question 84

Answer 84

Depigmentation

Question 85

Tack sites distribution

Answer 85

Question 86

Answer 86

Eosinophilic granulomas

Question 87

Answer 87

Staphylococcal foliculitis

Question 88

Answer 88

Staphylococcal folliculitis

Question 89

Answer 89

Mechanical abrasion

Question 90

Answer 90

Dermatophyte

Question 91

What must be included on PPEs?

Answer 91

• Examine, describe + record
• Categorise + form list of DDx e.g. “1 cm diameter area of alopecia and scaling skin on right side of face. Probable ringworm but other causes such as fly-bite, bacterial dermatitis or flat sarcoid cannot be discounted”