Diabetes Flashcards
Which breeds are predisposed in dogs?
Tibetan terrier and samoyed
Labs for juvenile onset
What is the pathogenesis of canine diabetes?
In most cases, canine diabetic patients have an absolute insulin deficiency, but in some cases, such as dioestrus diabetes and hyperadrenocorticism-associated diabetes, there may be a relative insulin deficiency accompanied by insulin resistance.
How do you diagnose diabetes?
persistent fasting blood glucose of 8 mmol/l could be adopted as a standard definition of canine diabetes mellitus especially when accompanied by appropriate
clinical signs. It is not uncommon for diabetic dogs to
have a blood glucose concentration much higher than this (greater than 20 mmol/l) at the time of first presentation;
therefore, a starved sample is not usually necessary
What can cause insulin resistance?
Primary insulin resistance diabetes (IRD) usually results from antagonism of insulin function by other hormones: diostrous/gestational diabetes; secondary to other endocrine disorders; hyperadrenocorticism; acromegaly; iatrogenic synthetic glucocorticoids; synthetic progestogens; glucose intolerance associated with obesity might contribute to insulin resistance but is not a primary cause of diabetes in dogs.
What can cause absolute insulin deficiency?
Congenital beta cell hypoplasia/abiotrophy;
Beta cell loss associated with exocrine pancreatic disease;
Immune-mediated beta cell destruction;
Idiopathic disease.
What are the ddx for hyperglycaemia?
Stress (cortisol and adrenaline response)
Diabetes mellitus or a prediabetic state
Other endocrine causes of insulin resistance – acromegaly, hyperadrenocorticism, dioestrus, hypothyroidism, hyperlipidaemia
Iatrogenic causes – total parenteral nutrition, exogenous glucocorticoids, glucose-containing fluid therapy, progestogens, megoestrol acetate and propranolol
Pancreatitis
Neuroendocrine tumour (eg, glucagonoma)
Exogenous pharmacological agents (eg, ketamine, medetomidine, megoestrol acetate and propranolol).
Other causes of insulin resistance, such as infection, inflammation
What are other common changes on biochem aside from high BG?
High cholesterol
High liver enzymes
High triglycerides
What should you consider investigating in a newly diagnosed diabetic?
Urine - including culture
Check for pancreatic disease/ EPI
How should you feed diabetic dogs?
twice daily, within one hour of each insulin injection. Some owners prefer to feed before the injection, especially if their dog has a history of a poor appetite, so that the insulin dose can be adjusted downwards to prevent hypoglycaemia if the animal does not eat
ensure exercise is the same each day too - and keep honey on walks just in case
What properties should a diabetic dog’s food have?
moderate amount (up to 30 per cent metabolisable energy) of complex and low glycaemicindex carbohydrates, while being low in simple sugars and fat (particularly important for pancreatitis and lipaemic patients). This limits the potential for post-prandial hyperglycaemia.
What complications are associated with canine diabetes?
Hypoglycaemia DKA hyperglycaemic hyperosmolar syndrome exocrine pancreatic disease Cataracts
How do you treat hypoglycaemia
Feed if able
Otherwise, glucose bolus (0.5g/kg), followed by CRI
If due to insulin overdose/ or if very severe, may need a glucagon CRI
What questions should you ask when assessing a glucose curve?
n Is there any evidence that the insulin is working? This can be assessed by looking to see if the blood glucose falls below the preinjection level at any point within 12 hours following the insulin.
How long is the insulin lasting? This is shown by the first point at which the blood glucose begins to rise again following the injection.
What is the nadir (lowest point) of the glucose curve
and is there any evidence of hypoglycaemia or rebound hyperglycaemia? It is important to assess these factors to reduce the chance of clinically significant and dangerous hypoglycaemia. If there is evidence of a rapid drop in glucose, followed by a sharp upward swing, then it is more likely that an insulin dose reduction is required rather than an increase.
How can you monitor diabetic patients?
Blood glucose curves (normally only needed in the early stages)
Owner diary
Outpatient clinics
fructosamine (can have limitations - more for monitoring trends in a single patient
Urinalysis
What are the main causes of poor diabetic control in dogs?
Management factors: such as out of date insulin, poor injection technique, lack of routine with food, exercise or insulin. This can be ruled out by taking a careful
and thorough history and by watching the owner inject insulin.
Insufficient dose/duration of action/activity of insulin: this will commonly be apparent from a blood glucose curve.
Too high an insulin dose: (Somogyi overswing) resulting in occasional episodes of hypoglycaemia interspersed with prolonged hyperglycaemia in response.
Infection or inflammation: leading to insulin resistance, such as pancreatitis, urinary tract infection, dental disease.
Hormonal antagonism: leading to insulin resistance eg, hyperadrenocorticism, dioestrus, exogenous (topical or systemic) steroid therapy, hypothyroidism.
Other individual patient factors: such as, poor insulin absorption, rapid insulin metabolism, anti-insulin antibodies (a very rare cause of clinical problems
