Equine: Alterations In The Skin.

Front 1

What are coat brushes good for identifying?

Back 1

Identifying mites like Chorioptes in horses feathers.

Front 2

What are hair plucks good for identifying? How long does it take a fungal culture to come back?

Back 2

Broken hair, crusts and scales to look for fungal spores.

Fungal culture for ringworm.

Fungal cultures take 14-21 days to come back.

Front 3

What diagnostic techniques can we use in our approach to a horse with skin disease?

Back 3

Coat brushings-->mites.

Hair plucks--> crusts, scales, broken hairs--> fungal

Skin scrapes.

Swabs--> moist lesion.

Fungal culture.

Aspirates--> masses and abscesses.

Impression smears.

Biopsy/punch--> diffuse skin disease like trusting.

Allergy testing--> intradermal or serum.

Photographs for sarcoids.

Front 4

If we are taking a biopsy in the case of diffuse skin disease what must we not do to the skin?

Back 4

We must not prepare it.

Front 5

What are causes of pruritic disease in horses?

Back 5

1) Pediculosis (Lice) biting or sucking.

2) Chorioptes equi.

3) Trombiculosis- T. autumnalis.

4) Oxyuris equi

5) Onchocercal dermatitis.

6) Sweet itch.

7) Atopy.

8) Urticaria/Hives.

9) Pemphigus foliaceus.

10) Multisystemic eosinophilic epitheliotrophic enteritis

11) Strongyloidosis- S. westeri.

Front 6

Signs of pediculosis in horses?Diagnosis?

Back 6

Pruritis, scaling and alopecia.

Wintered or poorly managed horses.

Cushings horse.

Diagnose: demonstration of lice and nits.

Front 7

Treatment for pediculosis?

Back 7

Insecticidal shampoos, sprays or powders with pyrethrins or pyrethroids.

Two applications at 14 day intervals.

Front 8

Where on horse is usually infected with Choriopte equi?Signs?

Back 8

Distal limb of heavily feathered horses.

Horses stamp and bite limbs. Scaling and exudation with secondary bacterial infection.

Front 9

How is chorioptes equi spread?

Back 9

Asymptomatic carriers, bedding, brushes, contact.

Front 10

How do we treat chorioptes in horses?

Back 10

Removal of hair and scabs compined with application of a insecticidal like fipronil or permethrins.

Systemic ivermectins and avermectins.

Seleen shampoo to reduce itch.

Front 11

Name the two types of louse that affect horses?

Back 11

Damalinia equi- biting louse.

Haematopinus asini- sucking louse.

Front 12

When do horses usually get infestation with trombiculosis in terms of season?

Back 12

Late summer and early autumn.

Nymphs lead to pruritus of the head and limbs.

Front 13

Why does Oxyuris lead to itching what is the problem with this disease in terms of treatment? Treatment?

Back 13

Oxyuris equi migrates from small colon rectum to lay eggs on the perianal skin causing intense pruritius and tail rubbing.

NEED TO TREAT THE ENVIRONMENT ALSO WHERE THE HORSE RUBS!!!!!!!

Treat with an ivermectin.

Front 14

How do we diagnose oxyuris equi?

Back 14

Skin tape on the perianal region!

May see worms coming out.

Front 15

What is the causative agent of Onchocercal dermatitis? How is it spread? Signs?

Back 15

Dermatitis caused by onchocerca cervicalis microfilaria transmitted by culocoides and other biting insects.

Larvae lodge in capillaries and signs are associated with type 1 and type 3 hypersensitivity reactions.

Puritius, allopecia, scaling of head, neck, ventral midline, withers and chest.

Focal dermatitis and exudation.

Front 16

What is the pathogenesis of sweetitch?

Back 16

Hypersensitivity reaction to the bite of culicoides midges.

Front 17

Where does sweet itch commonly effect on the body?

What are signs?

Back 17

Tail and mane.

Season signs of pruritis that is worse at dusk and dawn, aggressive rubbing causes self inflicted trauma.

Front 18

Treatment options for sweetitch?

Back 18

1) Management of skin lesions.

2) Corticosteroids.

3) Immunotherapy/ desensitisation treatment.

4) Fly repellants.

Front 19

How do we prevent midge bites?

Back 19

1) Oil based liquids like benzyl benzoate.

2) Stabling at dawn and dusk.

3) Rugs/hoods e.g. boett rug

4) Insect proof stables with meshes.

5) Fans/wind prevents midges landing.

6) Avoid rivers/water/woodland.

Front 20

What type of hypersensitivity reaction is atopy? Signs? DIagnosis? Treatment?

Back 20

Type 1 hypersensitivity to allergens.

Intense pruritis with secondary self inflicted trauma.

Diagnosis: intradermal skin testing, skin biopsies, serum ELISA or RAST tests.

Treat: avoid the allergen, immunotherapy or corticosteroids.

Front 21

Pathogenesis of uticaria/hives?

Back 21

Immune mediated/ allergy arises due to an injected drug like quinidine, ingestion of chemicals or feeds, inhaled pollens, moulds, chemicals.

Direct skin contact or mucous membranes.

Front 22

Clinical signs of Urticaria?

Back 22

Wheals that pig on pressure.

Pruritus from mild to severe.

Exudation sometimes from wheals.

Angio-oedema.

Front 23

Diagnosis and treatment plan for urticaria?

Back 23

Diagnosis based on signs, history, skin tests, ELISA or RAST, food elimination tests.

Treatment: Treat with short course of corticosteroids.

Single dose of I/V or I/M dexamethasone or oral prednisolone.

Front 24

What is the pathogensis of pemphigus foliaceus?

Back 24

Autoimmune disease characterized by exfoliative dermatitis leads to a type 2 hypersensitivity reaction due to auto-antibodies directed against cell membrane of epidermal cells.

Front 25

Signs of pemphigus folicaeus?

Back 25

Vesicles, pustules, erythematous scaling, crusting begins on the face and limbs, inflammation of coronary band, ergot and chestnut.

Painful/pruritic lesions.

Systemic signs of weight loss, pyrexia, inappetence, lethargy, ventral oedema.

Front 26

How do we diagnose and treat pemphigus? Prognosis ?

Back 26

Diagnose on biopsy.

Direct immunfluroscene shows immunoglobulin in epidermis.

Treat: High doses of corticosteroids.

Prognosis guarded.

Front 27

Signs of multisystemic eosinophilic epitheliotrophic enteritis?

Back 27

GIT and skin signs.

Ulcerative coronitis, alopecia, hyperkeratosis and exudation.

Intensely pruritic lesions.

Signs of generalized disease: pyrexia, weight loss, diarrhoea, lymphadenopathy,ventral oedema and dullness.

Front 28

Diagnosis and treatment of MEED?

Back 28

Skin biopsy also rectum and intestines.

Hypoprotaenmia, hypoalbumnaemia, hyperfibrogenaemia.

Treat: steroids.

Front 29

DDX list for alopecia in horses?

Back 29

Rain scald.

Dermatophytosis.

Sarcoids,

Linear keratosis.

Selenium toxicity.

Front 30

Cause of rain scald and signs?

Back 30

Cause is dermatophilus congolensis.

Signs: exudation, matted hairs, scabs in areas wetted by rain- back and quarters.

Paint brush lesions.

Front 31

Treatment for rain scald?

Back 31

Antibiotics.

Clipping and soaking of skin with chlorohexidine to remove exudates and scabs.

Topical AB.

Front 32

Back 32

Dermatophilus congolensis.

Front 33

What species commonly causes ringworm in horse? Less commonly? Signs?

Back 33

Tricophytan commonly. Less common microsporum sp.

Signs are circular erect lesions of hair, alopecia and scaling.

Front 34

How do we diagnose ringworm?

Back 34

Hair plucks and scrapes.

Woods lamp- trichophytan don't fluoresce, microsporum canis and equinum some fluoresce

Front 35

How do we treat ringworm?

Back 35

Topical antifungal like enilconazole, natamycin.

Treat enviroment with sporocidal natamycin or virkon.

Griseofulvin C/I in pregnant mares as teratogenic.

Front 36

What is alopecia areata? Signs? treatment?

Back 36

Cell mediated autoimmune skin disease characterized by thinning of the main and tail and reasonably circumcised areas of alopecia.

No effective treatment.

Front 37

Talk to me about linear keratosis and what horses it is mainly seen in?

Back 37

Idiopathic inherited dermatoisis mainly seen in quarter horses.

Unilateral, linear, vertical bands of hyperkeratosis and hairloss on neck, thorax and upper hind limb

Front 38

Name the most common skin tumour of horses?

Back 38

SARCOIDS.

Front 39

Name the 6 types of sarcoid?

Back 39

Occult--> flat plaque with hairloss.

Verrucose--> cauliflower.

Nodular--> complete s/c or intradermal or burst through skin.

Mixed

Fibroblastic--> ulcerative.

Malevolent--> invasive.

Front 40

Treatment of sarcoids?

Back 40

Benign neglect.

Surgery-laser,cryo, sharp excision.

Ligation.

BCG injection.

Liverpool cream.

Front 41

Believed cause of sarcoids?

Back 41

Bovine papillomavirus plays a role.

Front 42

DDX list for nodules, tumours and swellings?

Back 42

Insect bites.

Papillomas- viral and congenital and aural.

Sarcoids.

Melanoma.

Lymphosarcoma.

Eosinophilic collagen necrosis/granuloma.

Axillary nodular necrosis.

Cysts- dermoid, dentigerous, epidermoid.

Front 43

What age of horses is equine papilloma virus seen? Signs and treatment?

Back 43

Under 4 years old.

Signs lesions as small white-grey papules in huge numbers on muzzle, lips, eyelid, external genitals, limbs.

No need to treat as spontaneous resolve.

Front 44

What is shown in this image? Treatment?

Back 44

Aural papillomas.

No need to treat.

Front 45

Most common type of melanocyte tumor in horse? What colour of horse is predisposed? Where are they usually found?

Back 45

Melanomas around the perineum, sheath, parotid region and less commonly guttural pouch, eyelids, lips and iris.

Front 46

How do we diagnose/treat melanomas/melanosarcomas?

Back 46

Biopsy, FNAC- differentiation between two.

Treat by surgical excision, cryosurgery.

Cytotoxic drugs like cisplatin.

Cimetidine orally as histamine may be involved in tumour growth.

Front 47

What is shown here and what are signs? Treatment?

Back 47

Eosinophillic collagen necrosis/ granuloma.

Firm, painless skin nodules usually along back and side of chest.

Usually do not need to treat. Intralesional steroid or surgical excision.

Front 48

Where are epidermoid cysts most common?

Back 48

False nostril.

Front 49

DDX list for ulcerations and erosions in horses?

Back 49

SCC.

Habronemiasis.

Front 50

Aetiology of SCC in horses? Diagnosis and treatment?

Back 50

UV lights.

Smegma.

Diagnosis- Biopsy or impression smears for the ocular form.

Treatment options:

Surgical- excision like penile amputation, cryosurgery.

Cytotoxic/antimitotic drugs- intralesional cisplatin.

Radiation- most effective

Front 51

Cause of habronemiasis and signs?

Back 51

Granulating nodules/ wounds causes by larvae of habronema muscae, habronema majus and drachia megastoma.

Front 52

DDX for papules, pustules, vesicles?

Back 52

Staphylococcal dermatitis- s. aureus, s. intermedius, s. hyicus.

Front 53

Signs associated with staphylococcal dermatitis? Treatment?

Back 53

Painful skin lesions with folliculitis and furunculosis.

Treat with antibiotics based on C&S like penicillin and topical chlorohexidine.

REMEMBER CHECK RUGS AND REMOVE DAILY!

Front 54

DDX scaling and crustings?

Back 54

Pemphigus folliaceous- rare immune mediated disease- type II hypersensitivity to epidermal cells.

Actinic dermatoses.

Front 55

What must we differentiate sunburn from?

Back 55

Photosensitisation- Primary due to st johns wort or secondary due to liver failure.

Front 56

Reasons for actinic dermatoses?

Back 56

Sunburn.

Photosensitisation.

Front 57

Main ddx for abnormal coat?

Back 57

CUSHINGS- PPID

Caused by excessive POMC secretion leading to dysregulated release of ACTH and cortisoL!

Front 58

What is vitiligo?

Back 58

Leucoderma loss of pigment of the skin.

Front 59

DDX abnormal coat pigment?

Back 59

Leucotrichia- white hairs.

Leucoderma- vitiligo.

Front 60

DDX for pastern dermatitis?

Back 60

Chorioptes equi- feathered horses.

Secondary photosensitisation- accumulation of phylloerythrin due to failure by liver to exrete.

Mud fever- dermatophilus congolensis.

Pastern/cannon leucocytoclastic vasculitis.

Coronary band dystrophy/coronitis.

MEED.

Chronic progressive lymphoedema.

Front 61

Signs of mud fever? Diagnosis and treatment?

Back 61

Exudation, scabs, matting hair on distal limbs.

Diagnose with a smear.

Treat- A/B, anti inflammatories, soaking skin with chlorohexidine to remove scabs and exudate, clip hair, dry skin and apply topical A/B ointment.

Front 62

What is pastern/cannon leucocytoclastic vasculitis? Cause? Signs?Diagnosis? Treat?

Back 62

Skin condition of unpigmented distal limb.

Caused by UV light?

Signs: erythema, oozing and crusting of white distal limbs, similar to mud fever.

DIagnosis: Biopsy reveals a leucocytoclastic vasculitis, vessel wall necrosis and thrombosis.

Treat: clipping hair and removal exudate and crusts with chlorohexidine.

Topic antiseptic, antibiotics and steroids.

Sunblocks.

Leg wraps when out in sun.

Front 63

Cause of coronary band dystrophy and how do we treat it? Signs?

Back 63

Idiopathic/ immune mediated defect in cornification of coronary band.

Signs crack, fizzures, bleed and ooze.

Treat: symptomatic care of lesions, keep dry, and use steroids.

Front 64

Sequalae to mite infestation leading to dermatitis of the pastern?

Back 64

Chronic progressive lymphoedema.

Front 65

DDX list for limb swelling?

Back 65

Lymphangitis.

Cellulitis.

Vasculitis.

Purpura haemorrhagica.

Front 66

Aetiology of lymphangitis? What limbs usually affected? Signs?

Back 66

Inflammation of cutaneous lymphatics secondary to a bacterial infection obtained via a small cut/abrasion.

Hindlimb more than forelimb.

Signs: swelling, exudation, lame

Front 67

Treatment of lymphangitis of the limb?

Back 67

A/B based on culture and sensitivity.

NSAIDs/corticosteroids.

Diuretics and potassium iodide.

Hydrotherapy, cleaning with antimicrobials, leg wraps, gentle exercise.

Front 68

What is the aetiology of cellulitis? Signs and treatment?

Back 68

Wound infection that spreads through a tissue plane.

Affects limbs causing acute swelling, inappetence and pyrexia.

Treat: A/B, NSAID, hydrotherapy, cleaning with antimicrobials, gentle exercise.

Front 69

Aetiology of vasculitis? Causes? Signs? Treat?

Back 69

Inflammatory reaction in blood vessel walls usually type 1 or type 3 hypersensitivity.

Various infections or drugs may induce.

Signs oedema, necrosis and ulceration.

Treat: steroids.

Front 70

What is purpura haemorrhagica associated with in the limbs?

Back 70

Strangles infection.

Immune mediated vasculitis.