The flashcards below were created by user
on FreezingBlue Flashcards.
What are the 4 major presenting dermatology problems at vet clinics?
Pruritis (most common); otitis; alopecia; lumps and bumps (nodules, swellings and masses)
Summarise the problem oriented approach for dermatology cases
History, physical exam, problem list, differential diagnoses, diagnostic plan and tests, diagnosis, treatment
What specifics do you need for history in dermatology cases?
Background information, specific skin history, previous treatments, risk of heredity, infection or contagion, diet, environment and lifestyle, general health
Broadly, what history questions should you ask?
What's the problem, how long has it been present, has it changed over time? will cover most broad dermatology cases. Is it itchy? very important question
Is it itchy?
With pruritus, need to determine severity, affected areas, seasonality.
Why do a physical exam for a dermatology case?
Pathological changes are visible. Use vision, touch and smell. Include distance exam, look for lesions, critical to check distribution & examine whole animal. Look for parasites
What are the types of skin lesions?
Changes in skin colour, loss of hair, abnormal surface components, changes in skin thickness, defects in skin integrity, lumps and swellings
What causes erythema?
Redness, caused by vasodilation, inflamed skin, interchangeable with dermatitis. Non-specific sign. Causes: parasites, infections, allergies, environmental insults. Distribution map documents affected areas.
Why document or take note of lesion distribution?
Distribution is critical in dermatology, many conditions have specific distribution patterns
What are the different types of rashes?
- Macule: little flat circle of different colour.
- Papule: raised red pimple.
- Pustule: like papule but with sack of pus in middle, can squeeze.
What is a staphylococcal ring?
A circular area of alopecia, with circular erythematous macule or ring, and a peripheral ring of scaling (epidermal collarette). Get multiple lesions, common in dogs. Caused by S. aureus, S intermedius, S pseudintermedius
What is hyperpigmentation?
Increased melanin in dermis. Causes: post-inflammatory (some breed disposition), endocrine disorders (adrenal, gonads, sometimes thyroid)
What is hypopigmentation?
- Decreased melanin in dermis.
- congenital or hereditary (albinism),
- vitiligo (adult onset, melanocytes disappear),
- immune mediated,
- environmental (freeze branding),
What is alopecia?
- Loss of hair, can be partial or total including congenital.
- Distribution: focal, multifocal, symmetrical or generalised, scar
Causes of focal alopecia?
- Focal - a single spot, usually circular.
- Causes: demodecosis, dermatophytosis, trauma, scars
Causes of multi-focal alopecia?
- Multi-focal: many roughly circular patches of hair loss.
- Causes: staphylococcal folliculitis, demodecosis, dermatophytosis.
- All 3 have similar appearance due to similarity in disease process: follicle infection/infestation causes hair to fall out/break off, organism spreads out in circular fashion
Causes of symmetrical or generalised alopecia?
Endocrine diseases, hair cycling abnormalities. Can be congenital.
Scars destroy hair follicles, hair loss is permanent from scarred areas; includes wounds, burns, trauma, surgery
What are the abnormal skin surface components?
Excessive scaling, comedones, hyperkeratosis, crust
What causes excessive scaling?
- Non-specific clinical sign, covers any known skin disease.
- It is an abnormality of cornification due to increased turnover of stratum corneum, corneocytes clump together instead of separating when sloughed.
- Causes: parasites, inflammatory mediators, hormones, nutrition abnormalities or deficiencies, metabolic, environmental factors, primary cornification defect (genetic), neoplastic cells
What causes comedones?
- Comedones are blackheads, abnormality of follicular cornification, accumulation of abnormal corneocytes in hair follicle.
- Causes: demodecosis, hormonal skin disease
What causes hyperkeratosis?
Corneocytes not sloughed as normal, remain attached to skin surface. Relatively common in older dogs, usually nasal or digital. Can leave alone if not causing problems
What causes crust?
- Mixture of stratum corneum, cells (e.g. inflammatory), and tissue fluid (serum or blood). Scabs are a form of crust.
- Causes: pustular diseases, draining exudates, healing wounds.