Diabetes Mellitus

What is Diabetes Mellitus?

Diabetes Mellitus comes in two varieties, Type I and Type II diabetes.

Type I diabetes is characterised by very low levels of insulin secretion, or no insulin (a substance which is responsible for sugar processing in the body) production at all. Patients with type I diabetes face a life threatening illness if not treated with insulin.

Type II diabetes results from inadequate or delayed insulin production. Many patients with type II diabetes can live quite happily on controlled diets and without insulin supplementation.

What really happens?

Reduced amounts of insulin causes decreased ability of certain tissues to use glucose, especially muscle, fat tissues and the liver. I trying to overcome this, the body mobilises reserves of other energy sources such as proteins and fatty acids, which can lead to muscle wastage, weight loss and fatty accumulations in the liver.

Because the body can use less glucose as an energy source, it builds up within the blood. Once the amount of glucose in the blood reaches a certain level it overwhelms the kidneys and starts to be excreted in urine. This has a diuretic affect and increases the amount of urine being produced, causing your pet to go to the toilet more frequently. This fluid loss from the body increases thirst, so your pet needs to drink more water. High levels of glucose in the blood can also lead to cataracts forming in the lens of the eye (the pet can't see).

Who gets Diabetes Mellitus?

About 1 in 500 pet dogs or cats will develop diabetes. The most likely to be afflicted are obese animals, female dogs around 8 years of age and cats of any sex between 8 and 13 years old.

Other risk factors include severe pancreatitis, long term corticosteroid and hormone use and some immune-mediated diseases.

What do I look for?

Initial signs are:

  • Polydipsia and Polyuria (drinking lots and peeing lots)
  • Polyphagia (eating a lot)

Long term signs are:

  • Repeated urinary tract infections
  • Muscle wastage
  • Cataracts in dogs (often see cloudy eyes)
  • Cats can be standing and walking with the hock joints ("ankles") on the ground (plantigrade stance)

How does the vet test for diabetes?

Blood test is an essential part of finding out if diabetes is the problem, giving repeatable, high blood glucose readings. Blood glucose will also be high if a sample is taken when pets are stressed, such as after traveling in the car or if a little shy of needles.

Glucose present in a urine sample.

Can it be cured?

Diabetes can be treated but not cured. With a consistent diet high in fibre, complex carbohydrates and low in fats, insulin supplementation can stabilise blood glucose levels. Obese pets need to gradually reduce their weight and pets that are at a healthy weight need to keep their calorie intake constant.

Every pet is an individual when it comes to amount of insulin required to maintain blood glucose levels. Regular blood and urine glucose testing is needed to keep the insulin at a safe dose which "does the trick".