Skin and coat diseases Flashcards
Pruritus
Intense and persistent itching
Dermatitis
Inflammation of skin
Erosions
Ulcer that goes to depth of basement membrane
Erythema
Reddening of skin caused by capillary congestion
Exocoriation
Superficial erosions or ulcers caused by scratching or abrasion
Furunculosis
Deep infection of the hair follicle leading to abscess formation with accumulation of pus and necrotic tissue
Hyperkeratosis
Thickening of the stratum corneum from an increased number of keratinised cells
Plaques
Raised flat topped lesions
Pustule
Circumscribed epidermal or dermal accumulation of purulent exudate
What is pyoderma?
- Bacterial skin disease mainly seen in dogs
- Commonly seen as a secondary to other disorders
Seborrheoa
Increase in the scaling of the skin, with or without an increase in sebum production
What are the clinical signs and causes of pyoderma?
Clinical signs:
- Pustules
- Exudative lesions
- Scabs/crusts
- Scratching
- Pyrexia
- Odour
- Loss of appetite/behavioural changes
Causes:
- Staphylococcus intermedius
- Proteus Pseudomonas
- Pastuerella (cat bites)
What are the 3 types of pyoderma?
- Surface pyoderma (skin fold dermatitis/acute moist dermatitis)
- Superficial pyoderma (impetigo/folliculitis)
- Deep pyoderma (furunclosis/pododermatitis)
What is urticaria?
- Allergic dermatitis
- Causes multiple raised reddened circumscribed areas of erythema and oedema
- Usually pruritic
- Oedema may extend deep into dermis and subcutaneous tissues
- Usually seen in superficial layers
What are the causes and treatments for urticaria?
Causes:
- Drugs sensitivity
- Insect bites
- Bee/wasp stings
Treatments:
- Corticosteroids
- Removal of reason for reaction
What are the causes and treatments for urticaria?
Causes:
- Drugs sensitivity
- Insect bites
- Bee/wasp stings
Treatments:
- Corticosteroids
- Removal of reason for reaction
What is atopic dermatitis?
Itchy dermatitis in response to ingestion/inhalation/direct contact of antigens
What are the diagnostics of atopic dermatitis?
- Intradermal skin tests
- Multiple allergen tests
- Blood tests
What are the treatments for atopic dermatitis?
- Avoid contact with cause
- Injections of allergens
- Corticosteroids
- Essential fatty acids
- Antihistamines
What clinical signs are seen with hypothyroidism?
- Mainly seen in dogs and rare in cats
- Common in middle aged animals
- Slow regrowth of hair/seborrhoea/pyoderma/hyperpigmentation/bilateral alopecia
- Weight gain
What are the treatments for hypothyroidism?
- Hormone drugs (eg. levothyroxine)
- Treat cause and/or secondary skin disorders (eg. antibiotic/malaseb)
What clinical signs may be present with hyperadrenocorticism (cushings)?
- Bilateral alopecia
- Dull/dry hair
- Skin becomes thin/inelastic (especially ventral abdominal)
- Ascites (pot belly)
- Veins are visible
- Scaling of the skin
- Comedomes (caused by follicular plugging)
- Bruising
- More common in dogs
What treatment can be done for hyperadrenocorticism (cushings)?
- Surgical
- Medical
- Radiation therapy
What are some examples of hormonal alopecia?
- Hyperthyroidism
- Hyperadrenocorticism
- Sertoli call tumour
- Canine ovarian imbalance
What clinical signs are seen with hormonal alopecia?
- Hyperpigmented skin
- Dry and brittle coat
- Does not cause itching
What clinical signs may be seen with feline symmetric alopecia?
- Bilateral symmetrical alopecia
- Alopecia moves to forelegs (below elbow above carpus) and ventrally involving two thirds of the flank
- Cat can remain normal
What is the treatment for feline symmetric alopecia?
- Thyroid hormone replacement
- Megoestral acetate therapy
- Testosterone therapy (male and females)
What is hyperoestrogenism in male canines?
- Testicular tumour (Sertoli cell tumour) in middle/old entire dogs
- Skin disorder associated is bilateral alopecia
- Treatment is castration
What are the clinical signs of canine ovarian imbalance type I hyperoestrogenism?
- Seen in middle aged entire bitches
- Bilateral symmetrical alopecia beginning in perineal and genital areas
- Hyperpigmentation as disorder progresses
- Enlarged teats
- Seborrhoea (oily skin) and pruritus (itchy skin) may occur
- Normally seen in bitches with a history of abnormal oestrus cycles
- Often associated with ovarian tumours or cystic ovaries
- Treatment is to spay BUT symptoms may continue for a further 6 months
What is type II Oestrogen-responsive dermatosis?
- Female dogs that are prematurely neutered
- Alopecia in perineal/genital areas, spreading to flanks and upper legs
- Teats and vulva infertile
- Often incontinent
- Due to lack of oestrogen production
- Hormone therapy will be needed
What is dermatophytosis?
- A.K.A ringworm (fungal dermatitis)
- Round hairless patches will crusty, scabby skin
- May be sore or itchy but can also cause no discomfort
What is dermatophytosis?
- A.K.A ringworm (fungal dermatitis)
- Round hairless patches will crusty, scabby skin
- May be sore or itchy but can also cause no discomfort
What are the causes and treatment for dermatophytosis?
Causes:
- Fungal infection (dermatophytes)
- Trichophyton or microsporum families
Treatment:
- Isolate from other animals
- Clip around lesions/remove scabs
- Antifungal shampoos
- Repeat treatments
- Exposure to air and sun
What are the 4 stages of wound healing?
- Inflammation
- Debridement
- Repair
- Maturation
Explain how initial wound management would be carried out?
- Clean wound and remove necrotic tissue (debridement)
- If suspected infection culture should be taken
- Gently clean and flush wound at a pressure of 8psi (can be achieved using 18g needle)
- Wounds heal better when maintained in moist environment
- Ideally open wounds should be bandaged but not always possible
Explain how debridement can be carried out for wounds
Surgical:
- Drape as would for surgery
- Use scalpel to cut away necrotic tissue
- Change surgical kit once all damaged tissue removed
Debridement dressings:
- Used in initial stages until no infection or necrotic tissue present
- Do not leave on for longer than 24hrs
- Egs. hydrogels, hydrocolloids and adherent dressings
What are the types of healing processes recognised?
- Primary union/first intention healing
- Secondary closure/second intention closure
- Delayed primary union/third intention healing
Explain how each of the healing processes work
- First intention healing:
- Wound formed by clean incision and sutured immediately
- Minimal scar formation and skin edges unite firmly - Second intention healing:
-More significant tissue loss so not possible to close surgically
-Wound is left open to heal via granulation
-Use dressing and may progress to secondary closure in large wound
Secondary closure:
-Heavily contaminated, tissue damage
-Manage as open until good granulation cover then close - Third intention healing:
- Contaminated, manage as open until infection/FB removed
- Wound left open for a few days until granulation bed forms then its sutured (secondary closure)
What are the use of wound drains?
- Allows removal of fluid/gas from a surgical or traumatic wound
- Remove inflammatory mediators, bacteria, foreign material and necrotic tissue
- Relieve pressure
- Allow easy sampling of fluid during healing
- Eliminate dead space
What are the wound drain classifications and how do they work?
Open systems:
- Passive
- Rely on gravity
- Body movement
- Pressure differentials
- Overflow to remove gas/fluid
Closed systems:
- Active
- Rely on negative pressure created by the drain
What are some possible complications of drains?
Higher risk of infection
- Ascending infection
- FB reaction to brain
Vascular damage
-Pressure necrosis of arterial wall
Blockage
- Clogged
- Lose suction (active)
- Failure
Electrolyte imbalance
-High fluid production and loss leading to metabolic derangements and hypoproteinemia
