Diabetes Mellitus in Dogs
January 2, 2014
Diabetes is a disorder of metabolism that results from functional or absolute insulin deficiency. This means that the pancreas is either producing less insulin, or that the cells upon which the insulin acts are not accepting the insulin in the receptors normally, so effectiveness of the insulin is reduced. Insulin is the chief regulator hormone of the path that dietary carbohydrates and sugars take as they are processed, but insulin also affects fat and protein metabolism, and deficiency of this hormone has an adverse impact on all body systems. Metabolism is the set of chemical and physical reactions that the body uses to break down components of the diet into usable components such as fatty acids, simple sugars and amino acids, and to transfer stored energy and nutrients into usable components. During diabetes the body effectively goes into starvation mode.
There is no single cause of diabetes mellitus, but some hormonal diseases (Cushing's disease), pancreatic inflammation, and certain drugs are known to be associated with development of diabetes. In humans, Type I diabetes is the juvenile, insulin-responsive form and Type II is the type that generally affects those middle-aged, overweight, with low exercise levels. This latter type may respond to diet and exercise. Diabetes in dogs is also classified into Types I and II, and the latter is much more common.
Diabetes results in:
* weight loss
* increased thirst and urination
* increased appetite
* liver malfunction
* increased risk of chronic infections (e.g. bladder).
In later stages:
* loss of appetite
* death may occur if not treated.
There are some severe complications of untreated diabetes such as:
* non-ketotic hyperosmolar syndrome
A few breeds of dogs are known to be at higher risk for diabetes including Puli, Miniature Pinscher, Cairn terrier and Keeshonden. Also over-represented are Poodles, Dachshunds and Beagles. The onset of this condition varies; it can strike anywhere between 4 year and 14 years of age.
A complete blood count, biochemical profile, urinalysis, and interpretation of appropriate history signs (changes in thirst, weight, urinations) will provide the information needed to arrive at a diagnosis of diabetes mellitus. Elevated blood sugar and urine sugar levels are present in diabetes. The urine sample may also identify presence of ketones, a metabolic by-product that indicates a complication of diabetes (ketoacidosis) that requires intensive intervention. Many dogs have increased infections—many will show evidence of infection in the urinary tract.
Insulin therapy is easy to do, and your veterinary health care team will show you how to carry this out at home. It is very important to follow instructions for administration carefully. Improper storage, improper mixing and errors in dose can all have significant effect on the efficacy of the insulin treatment. The very fine, small insulin needles are well tolerated by dogs.
After insulin therapy has begun, a blood glucose curve will be recommended. This test is used to check how quickly a particular dog processes the insulin type prescribed, and how effective the combination of diet, exercise and insulin is for reducing blood sugar swings, and for lowering average blood sugar levels. This test is very important for the safety of long-term insulin therapy.
Diet must be customized to each patient. What is right for a middle-aged obese diabetic is wrong for a severely underweight diabetic. Generally, twice daily feeding is prescribed, coinciding with insulin injections. Obese dogs particularly benefit from high fibre diets. The fibre slows food absorption in the guts and this leads to reduced blood sugar peaks and troughs.
A low blood sugar crisis may occur if a dog receives an insulin overdose, or does not eat in association with an injection of insulin. This will produce weakness, lethargy, difficulty in arousing from sleep, and sometimes seizures. Application of corn syrup to the gums, and a prompt visit to the veterinary hospital is indicated because additional intravenous glucose will be needed until the pet is stabilized.
Oral hypoglycemic drugs may also be discussed in Type II diabetes as an alternative to insulin injections. Treating diabetes takes commitment from the owner. It is essential to follow up with recommended re-evaluations and ongoing therapy adjustments in order to provide adequate care. With good care though, dogs can have a good quality of life, and though we don't cure it, therapy allows the pet to lead a normal life.