05 - Primary Skin Lesions Flashcards
(Primary Lesions)
(macule)
- what is it?
- what is color like?
- Can it be pigmented?
- circumscribed, flat change in skin color
- may be depigmented, hyperpigmented (melanotic), erythematous, or result of local hemorrhage
- NO
(Primary Lesions)
(macule)
(Differentials)
- depigmented
- melanotic
- erythematous
- hemorrhagic
- post-inflammatory (often seen in horses); immune-mediated (lupus); vitiligo; drug eruption
- post-inflammatory or reaction to chronic inflammation; lentigo; early melanoma, sex hormone dermatoses, hypothyoidism, Cushing’s disease
- any acute dermatitis (allergic, parasitic, autoimmune, bacterial)
- thrombocytopenia, coagulopathy, vasculitis, insect bites
(Primary Lesions)
(Patch)
- what is it?
- can it be palpated?
- differentials?
- a macule greater than 1 cm in diameter
- NO
- same as for macules
(Primary Lesions)
(papule)
- what is it?
- it represents what?
- Can it be palpated?
- Are they erythematous?
- do they involve hair follicles?
- solid elevation of skin up to 1 cm in diameter
- infiltration of inflammatory cells, intraepidermal and subepidermal edema, or epidermal hypertrophy
- yes (always as a solid mass)
- often
- maybe
(Primary Lesions)
(papule)
(Differentials)
- What are they?
- Is a very common clinical presentatino of what?
- parasites (sarcoptic mange, follicular demodicosis)
superficial bacterial infection (follicular papules)
allergic conditions (flea allergy, contact allergy)
cause of feline miliary dermatitis
calcinosis cutis
sterile pyogranulomas
- superficial pyoderma
(Primary Lesions)
(plaque)
- what is it?
- results from what?
- large f_lat topped elevation_ often formed by extension or coalition of papules
- massive infiltration of inflammatory cells or neoplastic cells into the dermis or subcutis
(Primary Lesions)
(plaque)
(differentials)
- what are they?
- feline eosinophilic plaque
fungal infections (blastomycosis, sporotrichosis, cryptococcosis etc),
neoplasms
panniculitis (sterile, infectious)
calcinosis cutis
sterile pyogranulomas
(Primary Lesions)
(Nodule)
- what is it?
- results from what?
- circumscribed solid elevation of the skin greater than 1 cm in diameter
- massive infiltration of inflammatory cells or neoplastic cells into the dermis or subcutis
(Primary Lesions)
(Nodule)
(Differentials)
- what are they?
- Diseases that form nodules typically also form what?
- Bacterial infections
deef fungal infections
neoplasms
panniculitis (sterile, infectious)
calcinosis cutis
sterile pyogranulomas
- plaques (therefore, these lesions are often seen concurrently)
(Tumor)
- what is it?
- origin?
(differentials)
- neoplasia… a cutaneous tumor often present clinically how?
- a large mass that may involve any structure of the skin or subcutaneous tissue
- neoplastic
- as a plaque and/or nodule that may or may not ulcerate
(Primary LEsions)
(pustule)
- what is it?
- May be what in location?
- color is usually what?
- most commonly contain what?
but can also be what?
- Pustules are rarely seen in dogs and cats - why?
- small, circumscribed elevation of the skin filled with pus
- intraepidermal, subepidermal, or follicular
- yellow (may be green or red)
- neutrophils (and are infectious in origin)
eosinophils may predominate (especially in parasitic disorders) and may be sterile
- because they are formed superficially, are fragile and rupture easily resulting in crust formation
(Primary LEsions)
(pustule)
- Differentials?
- superficial pyoderma
demodicosis
sterile eosinophilic pustulosis
pemphigus foliaceous
subcorneal pustular dermatosis
(Primary LEsions)
(Abscess)
- what is it?
- pus is not visible until when?
- abcesses are what compared to pustules?
- demarcated, fluctuant lesion resuting from localized, dermal or subcutaneous accumulation of pus
- it drains to the surface
- larger and deeper
(Primary LEsions)
(Abscess)
(differentials)
- what are they?
- bacterial infections (cat fight abcess)
deep fungal infections
sterile panniculitis
(Primary LEsions)
(Vesicle)
- what is it?
- intradermal or epidermal?
- Vesicles are rarely seen in dogs and cats - why?
- sharply circumscribed elevation of the skin; up to 1 cm in diameter and filled with clear fluid
- either
- they are fragile and rupture easily