Endocrinology and dermatology Flashcards
What is the predisposition for equine metabolic syndrome?
Spanish horse derived breeds
UK native ponies, arabs and caspian-derived breeds
What are the 4 stages of insulin dysregulation?
- Lack of insulin response
- Increase in circulating insulin
- Compensated insulin dysregulation
- Uncompensated insulin dysregulation
What are some of the issues caused by EMS?
Laminitis
Strangulating small intestinal lesions
Increased risk of hyperlipaemia
Impairment of normal thermoregulation
Altered oestrus cycle, decreased fertility
Great risk of osteochondrosis dissecans in foals
What diagnostics can be used for EMS?
Basal glucose/insulin
OST/OGTT
CGIT
Are sweat glands present in the distal limb?
No
How long does the full hair cycle take?
4 to 6 weeks
What drives coat shedding?
Melatonin and prolactin
What is a type 1 hypersensitivity?
IgE mediated - release of histamine by mast cells. Aggravated by serial exposure. Sweet itch.
What is a type 2 hypersensitivity?
IgG mediated - cytotoxic response associated with complement binding.
What is a type 3 hypersensitivity?
Immunocomplex deposition on endothelial beds. Neutrophil activation - vasculitis
What is a type 4 hypersensitivity?
T-cell mediated. Insect bite or drug eruptions
What is a macule or patch?
Circumscribed, flat impalpable area of colour change
What is a papule?
Solid circumscribed, raised, firm, discoloured
What is a plaque?
Solid elevated, flat-topped
What is a vesicle?
Raised, fluid-filled, well-demarcated
What does PPID stand for?
Pituitary pars intermedia dysfunction
What breeds are pre-disposed to PPID?
Ponies and morgans
What are the early signs of PPID?
Muscle atrophy, hair abnormalities, dull, lacking energy, poor performance, regional adiposity.
What are the mid-late signs of PPID?
Metabolic shifts, secondary bacterial infections, hyperhidrosis/anhidrosis, PU/PD, hypertrichosis
What is the sensitivity and specificity of resting ACTH in moderate to advanced PPID?
Sensitivity: 89%
Specificity: 95%
What should be taken into consideration when testing resting ACTH?
Stress, excitement and trailering
Should not be collected within the first 30mins
What initial management should be used with PPID?
Pergolide administrated at initial dose 2ug/kg
Recheck plasma ACTH in 30 days
What vasoactive substances can trigger pruritus?
Histamine
Eicosanoids
Serotonin
Kallikrein
Bradykinin
What mite is found mainly on the distal limbs but also can be found in the groin/abdomen region?
Chorioptes equi
What mite affects the head, tail and ears all year around?
Psoroptes equi
What are clinical signs that a horse has a lice infestation?
Severe pruritus, self-mutilating, biting and rubbing
What is the colloquial name for oxyuris equi?
Pinworm
Where are oxyuris equi found?
Caecum and colon mucosa
When does sweet itch typically develop in the horse?
3 to 4 years old
What management can be used to reduce the effects of sweet itch?
Keep horses in stables at night with a rug. Use middle stables.
Regularly clean water troughs
Keep away from water sources
Reduce decaying vegetation and manure accumulation
What areas are affected with a food allergy?
Face, neck, trunk, angioedema, urticaria
What feeds commonly cause a food allergy?
Alfalfa, barley, beet pulp, bran and clover.
Feed additives and supplements
What type of hypersensitivity is a food allergy?
Type 1
What type of hypersensitivity is contact dermatitis?
Type 4
What is the colloquial name for dermatophilosis?
Rain scald
What medication can be used to treat dermatophilosis?
Penicillin for 3 to 5 days
TMPS for 2 weeks
What is dermatophytosis also known as?
Ringworm
What type of skin tumour accounts for 4-15% seen?
Melanomas
How old are grey horses when they typically develop melanomas?
4 to 8 years old
What type of melanoma can be described as: Single or multiple discrete nodules?
Melanocytic nevi
What type of melanoma can be described as: originating in the deeper dermis. Small singular or multiple nodules?
Dermal melanoma
What type of melanoma can be described as: Confluent large melanomas. Increased risk of metastasis?
Dermal melanomatosis
What type of melanoma can be described as: rare and invasive. Typically older horses and recurrent is very likely.
Malignant melanoma
What are the key features of sarcoids?
Benign, non-metastatic, locally aggressive, any equid, high recurrence
What are the 6 types of sarcoid?
Occult, verrucose, nodular, fibroblastic, mixed, malignant
How can occult sarcoids be identified?
Mild/stable/superficial
Hairless skin
Cutaneous nodules or roughened areas with mild hyperkeratotic regions
How can verrucose sarcoids be identified?
Rarely aggressive until injured
Rough hyperkeratotic appearance with some flaking or scalding around it
Warty-looking
How can nodular sarcoids be identified?
Variable size. Firm, spherical, subcutaneous nodules.
How can fibroblastic sarcoids be identified?
Ulcerated, fleshy, aggressive appearance
What is the second most common tumour in the horse?
Squamous cell carcinoma
Where are squamous cell carcinomas commonly found?
Areas that lack pigmentation, poorly haired - mucocutaneous junction
