Diabetes Mellitus Flashcards
What is the definition of Diabetes?
Clinically SIGNIFICANT insulin intolerance
what is type 1 diabetes mellitus?
Normal insulin sensitivity and islet underactivity
In dogs normally due to an immune mediated destruction of the islets
This is the case for most diabetic dogs
What kind of diabetes do dogs normally get?
Diabetes due to absolute insulin deficiency (type 1)
What is type 2 diabetes melitus?
Insulin resistance which initially leads to islet hyperactivity then islet underactivity as the islets become exhausted
Common with cats
Which species generally has variably reversible insulin deficiency?
Most diabetic cats
Commonly due to obesity, HAC or hypersomatotrophism
Which species generally has absolute insulin deficieny due to decreased islet number?
dogs
What is insulin resistance?
Decreased insulin activity leading to increased insulin secretion
What are the causes of insulin resistance?
Pregnancy, oestrus, obesity
Hormonal abnormalities (HAC, hypo/hyerthyroidism)
Decreased exercise
Illness
Hyperglycaemia
Increases in plasma NEFA concentration due to lipid disorders or other high levels of lipids
Pancreatitis
Idiopathic
How do you measure Pancreatitis? (in cats)
fPLI in the blood. On avergae higher in diabetic cats
What kind of diabetes does hypersomatotrophism cause?
Type 2
What do you generally measure to establish the presence of hypersomatrophism in cats?
IGF-1
Growth hormone plus Insulin –> IGF-1
Note IGF-1 probably not raised if insulin not present but GH not a good thing to measure as pulsatile secretion
What proportion of diabetic cats in the UK suffer from acromegaly?
1 in 4
What proportion of acromegalic cats have the classic phenotype?
1 in 4
Do all obese cats get diabetes?
Nope, need beta cell dysfunction as well
Genetic component?
What is the main age group for diabetes in dogs?
7-12 years
Why are females represtented more than males?
Because they get diestrus related diabetes. Increased progesterone –> Increased growth hormone at site of mammary gland –> insulin resistance
Is obesity a risk factor in the dog?
Not really no, they mainly get type 1
Which breed is most predisposed to diabetes?
Samoyed
What factors increase your chance of getting diabetes if you’re a cat?
Age, mostly over 10, obesity (3-5x increased risk), Neutering (2x increased risk) males (1.5x increased risk)
Which breed is over-represented in cat diabetes?
Burmese (2.3% get it)
Tend to get it when they’re older. If they have it their offspring have a 10% chance of getting it! Genetic component
What are the main clinical signs of an animal with diabetes mellitus?
Weight loss with increased appetite, polydipsia, polyuria, possibly decreased activity, depression
Will only have inappetance if has another disease as well or ketoacidosis.
Normal diabetes mellitus shouldn’t cause decreased appetite
If a diabetes patient has ketones in the urine what does this mean?
They have ketosis, doesn’t necessarily mean they are ketoacidotic
“Sad” diabetics (those with ketoacidosis) have ketonuria AND acidosis.
Those with ketoacidosis will be V+, D+, dehydrated and in a bad way
Which species can have cataracts associated with diabetes?
dogs
NOT cats
Are all diabetic cats obese?
Nope, some have no history of obesity
Why might you get ataxia with diabetes?
Diabetes can cause diabetic neuropathy
Which species is mot likely to get stress hyperglycaemia?
Cats! get it with illess and stress
What are the clinpath changes you’d expect to see in a diabetic animal?
Fasting hyperglycaemia
Fasting hyperlipidaemia
Glucosuria +/- ketonuria
+/- Metabolic acidosis
Altered potassium and phosphate
Elevated ALP and ALT
Elevated fructosamine and glycosylated haemoglobin
What does fructosamine represent?
Albumin with glucose irreversibly bound
When albumin is stable it represents average blood glucose over the last 3 weeks (ish)
hence can be used to monitor diabetic patients
What wil happen to fructosamine levels if there is low albumin?
The fructosamine levels will drop, not related to how much glucose there is!
Why do cows get ketosis?
Because they are in a negative energy balance, high glucose demand leads to NEFA –> ketone synthesis in the liver. Seen with a LOW blood sugar level.
What are the six principles/methods of diabetic treatment?
Correct underlying causes
Oral hypoglycaemic agents
Insulin preparation
Daily dose & dose frequency
Amount and type of food
Insulin and meal times
Is feline diabetes generally reversible?
Yes, by working on the acquired factors eg reduce abdominal fat, increase activity etc
How long do you nee to have hyperglycaemia for before histological abnormalities in the pancreas are evident?
(Glucotoxicity)
Around 2 weeks
Includes glycogen deposition and cell death
Why should you treat cats asap?
The greater the duration and degree of hyperglycaemia, the more severe the damage
What is the danger of aggressive diabetic treatment?
Hypoglycaemia
WHat are the three general ways we improve the state of diabetes?
Decrease demand for insulin, Increase sensitivity for insulin, Increase Insulin availability
If you have a female entire diabetic bitch, when should you neuter?
ASAP, no point trying to wait until diabetes is stable as will be intisically unstable until she is neutered!
What are Sulphonylureas?
They are oral hypoglycaemic agents (the only ones proven to be potentially useful in dogs and cats)
Why are oral hypoglycaemic agents not ideal
They are like red bull for the islets.
Allow compensation for a while but burn out the islets quicker and you need total exogenous insulin sooner.
Not really useful for dogs as their problem is because many of the islets destroyed. Only potentially useful for cats if it’s a situation of put them on it or euthanise, will not inject.
What is the most common sulphylurea agent used in animals?
Glipizide
How long after feeding is the glucose peak?
Around half an hour
How long does it take the insulin injected to take effect?
Around 2 hours
What is the only licensed insulin for dogs and what species is it derived from?
Caninsulin. Porcine derived
How many times do you generally have to inject cats and dogs daily?
BID (twice daily)
Most insulin preparations last longer or shorter in cats?
shorter (but variable)
Why is Detemir difficult to use in small dogs?
Very potent - small change in dose = big change in impact
Why should you rotate injection sites?
Causes inflammation and fibrosis at site which will alter absorption of the insulin
How should you go about monitoring response to treatment in diabetic animals?
Ask owner about water intake, polyphagia and measure weight
Clinical picture is very important
Glucose curves (every 2 hours for 12 hours once settled on insulin dose)
Fructosamine good for telling you average but bad for detail.
One off glucose measurement NOT sufficient for dose change; levels fluctuate
What should you do to calories in diabetic animals?
Give normal calorie requirement i.e. 60-80 kcal/kg
What kind of fat content should you have in diabetic food?
moderate
What levels of carbohydrates should you have for diabetic cats?
LOW levels of carbohydrates - better control and increased remission
Is there a proven specific diet that’s best for diabetic dogs?
NOPE! Just that it is palatable to the dog and will therefore be eaten reliably.
If there’s another disease that has a specific diet prioritise this
What kind of insulin should you give a dog and how often?
Lente insulin (eg caninsulin) about 12 hours apart
If the glycaemia values look perfect but owner reports wobbly cat, should you worry?
YES! hypoglycaemia
Do you get remission in dogs?
Not in a classic type 1 case, may be reversible if due to HAC, diestrus related etc
What are the reported remission rates in cats?
25-50%
How regularly should you monitor cats with diabetes if you’re trying to get them into remission?
Every 12-24 hours, but don’t change the dose this frequently!
Animal insulins are more longer acting than those that suggest daily dose change protocols in humans
How quickly should you reduce the insluin dose once remission achieved?
Don’t be in a hurry
Reduce by 05 - 1 mg every few days
then to once daily dosing - 1 mg/cat/24h
check glucose evvery 12 hrs post insulin
only stop insulin totally if euglycemic at 12hrs
Continue low carboydrate diet
Does the dose tend to increase or decrease in dogs?
Increase
tend to stabilise at around 0.75units/kg/12h
Need consistent diet
What do you start cats on as a starting dose of insulin?
About 1 unit/cat/12h
Will end up probably on around 2 units/cat/12hr
What drug would you give to an animal that comes in with ptonic clonic seizure?
Place catheter and give midazolam/diazepam
True or false, hypoglycaemia can cause a seizure AND a seizure can cause hypoglycaemia?
true
Is it easy to get hypoglycamia from fasting?
Nope, need to be fasting for very long time before you will get hypoglycaemia
How badly would the liver need to be damaged to give you hypoglycaemia? (due to liver damage)
Very damaged, needs to be in failure
What is a stress leukogram?
Lymphopenia, netrophila, monocytosis
Occurs due to raised cortisol. If fitting and this is absent think addisons.
What does normal insulin levels in the presence of hypoglycaemia suggest?
Unregulated insulin secretion, if hypoglycaemic, should be shutting down insulin secretion, not chucking out normal amounts.
