What is Diabetes?
Diabetes is a chronic endocrine disease characterized by high blood glucose (sugar) levels. Glucose comes from your pet’s diet and is required by the cells of the body for energy. Blood glucose is regulated by the hormone insulin, which is made by the pancreas. Insulin is required by the body in order for glucose to get transferred from your pet’s bloodstream into the body’s tissues and cells.
If there is not enough insulin produced or the body is unable to use the insulin (insulin resistance), glucose accumulates in the blood and urine. When the body is unable to absorb the glucose from the bloodstream, the body will start to break down fat and protein stores for energy leading to weight loss as well as the production of byproducts called ketones.
How did my pet get diabetes?
Diabetes occurs most commonly in middle-aged to older dogs and cats. Some breeds are at an increased risk including the miniature schnauzer, miniature poodle, toy poodle, Samoyed, and pug.
The most common cause of diabetes is destruction of beta cells in the pancreas, often secondary to chronic pancreatic inflammation. The beta cells are responsible for insulin production. This is known as Type I Diabetes. Other causes of type I diabetes include obesity, genetically inherited, poor quality diet, stress, certain medications, or hormonal abnormalities (i.e. Cushing’s disease or acromegaly). Type I diabetes is more common in dogs.
Type II diabetes occurs due to resistance to insulin in the body or inadequate insulin secretion by the pancreas. This type of diabetes may or may not need insulin. In the cases that do require insulin, your pet may go into remission after a period of time. Type II diabetes is more common in cats and is often due to obesity.
Clinical Signs
- Increased thirst and urination
- Increased appetite
- Weight loss, muscle wasting along the back
- Lethargy and/or weakness
- Cataracts
- Symptoms of a urinary tract infection may be seen: frequent urination, blood in the urine, straining to urinate, inappropriate urination, or foul-smelling urine.
- Severe cases: vomiting, depression, weakness, dehydration, rapid breathing
- Less common: a plantigrade stance (lower part of the rear legs is dropped toward the ground so cat is walking on its lower leg)
Diagnosis
Your veterinarian will perform a thorough physical exam and obtain a health and diet history. Diabetes may be suspected based on clinical signs listed above. Diagnosis is achieved by the presence of elevated glucose levels in your pet’s blood and urine. Initial testing includes complete blood count, biochemistry profile, and urinalysis. Additional testing may be performed to rule out other conditions that may complicate the treatment of diabetes (infections or other hormone disorders). Such tests may include a urine culture, abdominal x-ray, abdominal ultrasound, baseline cortisol or ACTH stimulation test and thyroid screen.
Treatment
There is no cure for diabetes and treatment will be required for the rest of your pet’s life. Treatment of diabetes is multifactorial and requires insulin injections, a proper diet, and maintaining a healthy weight through regular controlled exercise. Several forms of insulin are available, your veterinarian will help decide which is best for your pet. Insulin injections are needed twice daily (every twelve hours) with a meal; see below for more details on insulin handling and administration. Rarely, some diabetic cats can be controlled with diet, weight loss (if overweight), and oral hypoglycemic medications.
A diet change may also be recommended. A low fat, high-fiber food with complex carbohydrates is best for your diabetic pet. Cats should be fed a high protein, low-carb diet. There are prescription diets available for both dogs and cats that meet this requirement. Not every pet will tolerate a diet change. In these cases, the most important thing is that your pet is on a consistent twice daily feeding schedule with a single type of food that the pet enjoys. Diabetic control is difficult if your pet’s food varies, this includes treats. Treats and table scraps should be avoided. Some treats have sugar coatings as a preservative which will greatly affect the regulation of your pet’s diabetes.
Exercise and activity levels should be regulated and consistent. If your pet is overweight, a weight loss plan may be recommended. Excess body weight decreases tissue responsiveness to insulin. In this case, your pet’s blood sugar will need close monitoring and frequent adjustments to the insulin dose may occur until a stable weight is achieved.
In more severe cases (diabetic ketoacidosis), your pet may require hospitalization for IV fluids, starting insulin, and frequent monitoring of blood sugar.
Monitoring & Follow-up Care
Monitoring is very important in order to keep your pet’s blood sugar within an optimal range. A combination of home and in-clinic monitoring is often required. Home monitoring involves monitoring appetite and food intake, activity level, body weight, water intake, and frequency of urination. Your veterinarian may also recommend that you learn to use a glucometer, a device that enables you to check your pet’s blood sugar level at home.
About one week after beginning insulin therapy, your pet should be scheduled for a blood glucose curve in the clinic. A glucose curve is obtained by checking your pet’s blood glucose level several times over the course of the day to determine how your pet is responding to the prescribed insulin dose. Based on test results, the dose of insulin may be adjusted.
After the initial in clinic curve your veterinarian will make a plan with you for future monitoring. Monitoring may involve a combination of different tests such as blood glucose spot-check, a blood glucose curve, and a fructosamine level. Fructosamine levels can be used to evaluate how the blood glucose levels are regulated over a longer period of time. A glucose curve in clinic will be recommended any time your pet’s insulin dose is changed or every six months. Other laboratory tests may be performed to look for complicating conditions if it is determined that your pet’s diabetes is poorly controlled.
Possible Complications
If you notice the following symptoms, please contact a veterinarian right away as your pet may be in a diabetic crisis. Things that may indicate an overdose of insulin include:
- Seizures, focal twitching, coma, poor appetite, changes in normal behavior, depression or lethargy, weakness or stumbling. These are an indication that your pet’s blood sugar is too low.
Your vet may recommend giving 1-2 tsp of Karo syrup by mouth or rubbing the karo syrup on the gums, this will temporarily increase the blood sugar level. Your pet will still need veterinary attention.
Other complications of diabetes mellitus may include kidney damage (“diabetic nephropathy”), nerve damage (“diabetic neuropathy”), or cataracts (in dogs).
Prognosis
Diabetes can be challenging to regulate and may require a bit of patience and persistence. Your pet may be more susceptible to infections, slow wound healing, cataracts, pancreatitis, gastrointestinal problems, and nervous system disorders. Successful treatment requires that you learn to give injections, and become familiar with the signs of insulin overdosage and underdosage.
With proper monitoring, treatment, diet, and exercise, diabetic pets can lead long happy lives.