PRIMARY LESIONS

Question 1

(Macule)

1. What is it?

Answer 1

1. circumscribed, flat change in skin color. May be pigmented, hyperpigmented, erythmatous or a result of local hemorrhage. CANNOT BE PALPATED

Question 2

(Patch)

1. What is it?

Answer 2

1. macule greater than 1 cm in diameter. CANNOT BE PALPATED

Question 3

(papule)

1. what is it?
2. represents what?
3. Can it be palpated?
4. are erythmatous, may contain hair follicles
5. differentials?

Answer 3

1. solid elevation of the skin up to 1 cm in diameter
2. infiltration of inflammatory cells, intraepidermal and subepidermal edema, or epidermal hypertrophy
3. yes (as a solid mass)
4. parasites (sarcoptic mange, follicular demodicosis)

superficial bacterial infection

flea allergy

feline miliary dermatitis

very common clinical sign of superficial pyoderma

Question 4

(Plaque)

1. what is it?
2. results from what?
3. diff?

Answer 4

1. large flat topped elevation formed by extension or coalition of papules.
2. massive infiltration of inflammatory cells or neoplastic cells into dermis or subcutis
3. feline eosinophilic plaque

fungal infections

neoplasms

Question 5

(nodule)

1. what is it?
2. results from what?
3. diff?

Answer 5

1. circumscribed solid elevation of the skin greater than 1 cm in diameter
2. massive infiltration of inflammatory cells or neoplastic cells into the dermis or subcutis
3. deep fungal infections

neoplasms

panniculiits

sterile pyogranulomas

Question 6

(Tumor)

1. what is it?
2. origin?
3. often present as what?

Answer 6

1. large mass that may involve any structure of the skin or subcutaneous tissue
2. neoplastic
3. plaque and/or nodule that may or may not ulcerate

Question 7

(Pustule)

1. what is it?
2. location?
3. color?
4. contain primarily what?
5. how common in dogs/cats?
6. diff?

Answer 7

1. small, circumscribed elevation of the skin filled with pus
2. intraepidermal, subepidermal, follicular
3. yellow (green or red)
4. neutrophils and are infectious in origin (but can be eosinophils is parasitic disorders)
5. rare - they are fragile
6. superficial pyoderma, demodicosis, pemphigus foliaceous

Question 8

(Abscess)

1. what is it?
2. is pus visible?
3. how compare in size to pustules?
4. diff?

Answer 8

1. demarcated, fluctuant lesion resulting from localized, dermal or subcutaneous accumulation of pus
2. not until it drains to surface
3. larger and deeper
4. bacterial infections

Question 9

(Vesicle)

1. what is it?
2. location?
3. how often in cats’dogs?
4. diff?

Answer 9

1. sharply circumscribed elevation of the skin; up to 1 cm and filled with clear fluid
2. intraepidermal or subepidermal
3. rarely cause fragile
4. autoimmune disorders

viral diseases

chemical irritants

Question 10

(Bulla)

1. what are they?
2. diffs same as for vesicle

Answer 10

1. vesicles larger than 1 cm

Question 11

(Cysts)

1. what are they?
2. usually lined by what?

and contain what?

Answer 11

1. epithelial lined cavity filled with fluid (eg secretion of apocrine glands) or solid material (keratin)
2. skin adnexa structures (hair, sweat glands)

keratin, sebaceous or apocrine secretions

Question 12

(Wheal)

1. what is it?
2. examples are what?
3. most commonly seen in what animals?
4. diffs?

Answer 12

1. circumscribed raised lesion consisting of edema that appears and diappears in minutes to hours
2. hives and positive skin tests
3. horses and dogs
4. allergic or nonallergic uticaria (hives)

Question 13

(Angioedema)

1. what is it?
2. how is lesion than in hives?
3. does it pit when pressed?

Answer 13

1. when the edema extends into the subcutis
2. lesion is diffuse and not sharply circumscribed
3. yes