An Introduction To Diabetes Mellitus

Diabetes is a disease about which we hear a great deal in a human context. However it is also very important in the veterinary world. There are of course two forms of Diabetes: mellitus and insipidus, as they are called.

However it is Diabetes mellitus, which is certainly the most common form.

Diabetes mellitus is known colloquially as "Sugar diabetes" as it results in excessively high levels of blood sugar(glucose), and the presence of glucose in the urine. Symptoms of diabetes include a grossly exaggerated thirst, loss of weight, a sweet smell on the breath, a worsening appetite, and later on, cataracts can develop in the eyes. It certainly occurs in both dogs and cats, but is more common in the former. Bitches are supposed to be the more likely of the two sexes to contract the condition, but many male dogs also suffer from it.
Often an owner will come into the surgery complaining that their dog has suddenly started wetting in the house. Often it is a very well trained, older dog, and this behaviour is quite out of character. On further questioning it may turn out that the pet has been drinking rather more water than used to be the case. There may be some loss of weight. Another old fashioned term for sugar diabetes was" starvation in the midst of plenty". This was meant to describe the fact that the blood sugar level was very high, yet for some reason the body was unable to utilise that glucose resource. The cause of this "starvation" we then discovered to be a lack of the hormone insulin. Damage to specific clusters of cells in the pancreas, which release the insulin, is indeed the root cause of this sad condition. Nevertheless, both in dogs and in cats, Diabetes Mellitus is quite treatable nowadays.

Treatment depends on finding a way of replacing the deficient hormone, or by reducing the body's need for insulin. The primary treatment usually involves direct replacement of insulin using once or even twice daily injections given just under the skin. Many of our patients have owners who have learnt to carry out this simple procedure themselves. However, although giving the injection is quite easy -unless you have a very uncooperative dog! - there is rather more to the whole procedure: The body's need for insulin tends to fluctuate.

The normally working pancreas is a wonderful complex organ, which monitors the precise requirement for insulin and "drip-feeds" it into the bloodstream. This monitoring function has to be replaced as it stops working in the diabetic patient, and is carried out by the vet, and involves the production of a “blood glucose curve”. Blood glucose levels are measured every hour or two for a prolonged period following the administration of the patient’s daily insulin injection. From the shape of the graph produced, the vet can decide whether the insulin dose is correct, or needs to be increased or decreased. This glucose curve procedure may need to be carried out many times before a stable daily regime can be achieved. It then needs to be repeated on a frequent basis, in order to ensure that insulin needs are not changing. This is NOT a static disease, and the treatment needs to move with the needs of the patient, and as closely as possible.

Having achieved a stable daily insulin regime, owners usually notice a dramatic improvement in the animal's condition almost immediately. Dietary techniques can be very helpful. Certain high fibre diets have been developed to help diabetic dogs and cats. Such diets help to reduce the need for insulin, and make it easier to maintain stability.

Over and above the insulin treatment, one or two other helpful things can be done. If the patient is a bitch who has not been spayed, then your vet may well recommend that she be neutered. Unspayed bitches are subject to violent variations in their insulin needs, especially around the time of their season, and this makes treatment very difficult. And sometimes, Diabetes mellitus can occur in combination with other hormone problems, notably a condition called "Cushing's Syndrome" – such a situation complicates the situation further, to say the least!