Skin Lesion Recognition

Question 1

Types of skin lesion

Answer 1

Primary, secondary or both

Question 2

Level of skin lesion

Answer 2

Flat, elevated, depressed

Question 3

Primary lesion

Answer 3

Direct result of disease process
Early lesion
Not altered by trauma

Question 4

Examples of primary lesions

Answer 4

Papules Macules Vesicles Nodules Pustules Patches Bullae Cysts Plaques Wheals

Question 5

Papule

Answer 5

Small solid elevation
Up to 1cm
Due to infiltration of inflammatory cells and edema
- flea bites, superficial bacterial folliculitis

Question 6

pustule

Answer 6

Small circumscribed elevation filled w purulent material
Intra epidermal, follicular or non follicular
- bacterial infection, pemphigus foliaceus

Question 7

Pemphigus foliceus early lesion

Answer 7

Non follicular pustules

Question 8

Pemphigus foliaceus late lesions

Answer 8

Leads to crust and erosions

Question 9

Plaque

Answer 9

Flat topped elevation
Formed by coalition of papules
- eosinophilic plaques in cats
Calcinosis cutis (cushings)

Question 10

Wheal

Answer 10

Sharply circumscribed raised lesion or hive
Consist of edema
Appear/disappear within m to h
- urticaria, insect bites, intradermal test

Question 11

Macula

Answer 11

Flat circumscribed skin discoloration <1cm in diameter
Lacks surface elevation or depression
-loss of pigment, erythema (red), hyperpigmentation
Common in vitiligo, atopic dermatitis

Question 12

Patch

Answer 12

Flat circumscribed skin discoloration >1cm in diameter
Canine atopic dermatitis

Question 13

vesicle

Answer 13

Sharply circumscribed elevated lesion <0.5cm
Contains fluid
- viral disease, autoimmune disease (chicken pox lesion)
Same thing as a bulla just smaller

Question 14

Bulla

Answer 14

Sharply circumscribed elevated lesion >0.5cm*
Contains fluid
- common lesion in autoimmune disease
Same thing as a vesicle just bigger

Question 15

Nodule

Answer 15

Solid circumscribed elevated lesion >1cm in diameter
Usually extends into dermis
- neoplasia, deep infection, immune mediated lesion

Question 16

Cyst

Answer 16

Nodule containing fluid or semisolid material
- follicular cyst, Infundibular cyst, apocrine cyst

Question 17

Secondary lesion types

Answer 17

Erosions Ulcers Excoriations Fissures Scars Epidermal collarette Lichenification

Question 18

Erosion

Answer 18

2nd
Partial loss of epidermis, does not penetrate basement membrane, heals without scaring

Question 19

Ulcer

Answer 19

2nd
Full loss of epidermis, penetrate and extend beyond basement membrane, heals w scarring (in chronic cases)

Question 20

Excoriation

Answer 20

2nd
Linear erosion induced by scratching or trauma
Seen in pruritic dermatoses
- atopic dermatitis, scabies, pyoderma

Question 21

Fissure

Answer 21

2nd
Verticals loss of epidermis and dermis with sharply defined walls/cracks in the skin

Question 22

Scar

Answer 22

2nd
Formation of new connective fibrous tissue
Implied prior damage that extended beyond basement membrane

Question 23

Epidermal collarette

Answer 23

2nd
Circular ring of scales w erythema
Non-expanding - footprint of ruptured pustule
- superficial pyoderma
- sterile pustular dermatosis
expanding
- collarette expands, peeling/lifting of stratum corneum, exfoliating toxins by staph Pseudointermedius

Question 24

Non expanding collarette

Answer 24

Non-expanding - footprint of ruptured pustule
- superficial pyoderma
- sterile pustular dermatosis

Question 25

Expanding collarette

Answer 25

expanding - collarette expands, peeling/lifting of stratum corneum, exfoliating toxins by staph Pseudointermedius* most common cause of pyoderma in dogs

Question 26

Lichenification

Answer 26

Marked thickening of all layers of epidermis Resembles tree bark Accentuation of skin lines Caused by chronic rubbing or scratching - canine atopic dermatitis

Question 27

Hyperkeratosis

Answer 27

Increase in the thickness of the stratum corneum • Associated with: Atopic dermatitis with malassezia dermatitis, Chronic low-grade trauma/barrier damage or secondary infection Zinc- responsive dermatosis, malassezia dermatitis, ectoparasitism

Question 28

Primary or secondary lesions

Answer 28

Alopecia Scales Crusts Follicular casts Comedones Hyperpigmentation/hypopigmentation

Question 29

Spontaneous (primary) alopecia

Answer 29

Border of lesion has a sharp margin Tip of hair usually not affected Easily epilated hair shaft at borders - Dermatophytosis, dermodicosis, ischemic Dermatopathy

Question 30

Self induced (secondary) alopecia

Answer 30

Border of lesion may have indistinct margin Tip of hair at border is broken Hair shaft isn’t easily pulled

Question 31

Scale

Answer 31

Accumulation of loose fragments of stratum corneum - flakes Due to maturation of epidermis or glandular secretion

Question 32

Primary scaling lesion

Answer 32

Primary seborrhea of spaniels Ichthyosis Sebaceous adenitis

Question 33

Scaling secondary lesion

Answer 33

Xerosis (dry skin) Flea allergy dermatitis Canine atopic dermatitis Pyoderma Ectoparasites

Question 34

Crust

Answer 34

Collection of cellular debris, dried exudate, inflammatory cells or blood - yellow, honey, dark red, brown

Question 35

Primary crust lesion

Answer 35

Zinc responsive dermatosis Hepatocutaneous syndrome

Question 36

Secondary crust lesion

Answer 36

Pyoderma Pruritus Pemphigus foliaceus

Question 37

Follicular cast

Answer 37

Accumulation of keratin and sebaceous material that adheres to hair shaft Primary associated w - primary seborrhea, sebaceous adenitis Secondary lesion associated w - Dermatophytosis, dermodicosis

Question 38

Comedo

Answer 38

Dilated hair follicles filled w cornified cells & sebaceous/sweat gland secretions Primary lesion of feline chin acne, schnauzer comedo syndrome Secondary lesion of hyperadrenocorticism, dermodicosis

Question 39

Colors of lesions

Answer 39

Erythema Petechia /purpura Hypopigmentation Hyperpigmentation

Question 40

Erythema

Answer 40

Redness of skin - rash Caused by congestion (vasodilation) of BV in dermis Blanches on pressure - diascopy - allergic dermatosis, cutaneous drug reaction, cutaneous lymphoma

Question 41

Petechia/purpura

Answer 41

Dark red/purple Caused by extravasation of RBC into dermis - hemorrhage Does not blanch on pressure Petechia < purpura < ecchymosis - vasculitis, drug reaction

Question 42

Hypopigmentation

Answer 42

Lighter than normal skin color Depigmentation = total loss of pigmentation (white) - vitiligo, cutaneous lymphoma, albinism, uveodermatologic syndrome

Question 43

Hyperpigmentation

Answer 43

Darker than normal skin color - hypothyroidism or post inflammation response

Question 44

Primary lesions that are only different in size

Answer 44

Macule vs patch Vesicle vs bulla

Question 45

Primary lesion filled w fluid/inflammation

Answer 45

Papule - inflammatory cells & edema Pustule - purulent material Wheal - edema Vesicle & bulla - fluid Cyst - fluid/semisolid material

Question 46

What primary lesions are flat?

Answer 46

Plaque Macule Patch

Question 47

What primary lesions are raised?

Answer 47

Papule Pustule Wheal Vesicle Bulla Nodule Cyst

Question 48

Multiple papules form a

Answer 48

Plaque