Intro/Basic Terms Flashcards
What are the two most common reasons owners bring their pets to the vet?
- Skin allergies
2. Ear infection
What are the primary lesions?
Macule Papule Plaque Pustule Vesicle Bulla Nodule Wheal Tumor
What is a macule?
An area of skin altered in color but not elevated
>1 cm is called a patch
What is a papule?
Solid, raised lesion that has distinct borders and is less than 1 cm in diameter
What is a plaque?
Elevated lesion with flattened top, greater than 10 mm in size
What is a pustule?
Elevations filled with pus, common in bacterial infections and other inflammatory skin diseases
Follicular vs non-follicular
What are some differential diagnoses for follicular pustule eruption?
Demodex
Dermatophytes
Baxcterial
What are some differential diagnoses for non-follicular pustule eruption?
Flea, food, contact allergies Scabies Drug Dermatomyositis Autoimmune
What is a vesicle?
A small, clear fluid-filled blister less than 1 mm in diameter
May be caused by acute contact dermatitis and some autoimmune skin diseases
What is a bulla?
A clear, fluid-filled blister >10mm in diameter
May be caused by burns, contact dermatitis, drug reactions, autoimmune diseases
What is a nodule?
Firm lesions that extend into the dermis or SQ tissue
What is a tumor?
Swelling or enlargement that is usually, but not always, neoplasitc
What is a wheal (hive)
A sharply circumscribed skin elevation produced by edema of the superficial dermis
Typical of allergic reactions
Can differentiate from other lesions by diascopy
What are secondary lesions?
Epidermal collarettes Scale Crust Scar Ulcer Excoriation Lichenification Hyperpigmentation Hyperkeratosis
What are epidermal collarettes?
Secondary lesions developed from previous pustules
What are scales?
Flake of abnormal or compacted epithelial cells
What is a crust?
Dried exudate (leukocytes or bacteria)
What is a scar?
Fibrotic area resulting from healing of a wound or lesion
Typically associated with alopecia, depigmentation, and/or thinner dermis
What is an ulcer?
Loss of substance on a cutaneous surface exposing inner layers of tissues
May imply full thickness loss of epidermis
What are excoriations?
Superficial erosion
Usually implies scratching or abrasion
What is lichenification?
Thickening of skin
Secondary to chronic trauma/infection
What is hyperpigmentation?
Increased pigmentation commonly associated with lichenification
What is hyperkeratosis?
Thickening of the stratum corneum due to an increased number of keratinized cells
What is depigmentation?
Loss of pigmentation, typical of inflammatory/neoplastic processes affecting the basement membrane
Direct microscopic exam is useful for what?
Detection of arthrospores
Cytology is useful for what?
Diagnosing secondary infections
