Diabetes Mellitus (DM) is named for having sugar in the urine. Typical signs of diabetes are increased thirst and increased urination. Untreated diabetics will initially have an increased appetite, but may lose weight. Weight loss is both loss of fat and muscle. Other signs of diabetes may include anorexia, dehydration, unkempt appearance, weakness, depression, vomiting, and gait abnormalities. Diabetes may not even be detected until secondary cataracts form and impair vision. In dogs, females are two times as likely to become diabetic, whereas in cats, males are 1.5 times more likely to develop diabetes. Diabetes is common in dogs and cats that have been obese or have had pancreatic disease. Obesity can both lead to diabetes and increase the difficulty in controlling diabetes. Diabetes may develop with either reduced insulin secretion, or with insulin resistance. Many times, a combination of these two conditions exists.
Specific cells in the pancreas normally secrete insulin in response to elevated blood sugar. Insulin acts by allowing cells of the body to take sugar out of the blood stream to nourish them. Without insulin, there may be sugar in the bloodstream, but the cells cannot access it. When blood sugar elevates high enough, (a condition called hyperglycemia), sugar will enter into the urine, pulling water with it. This can lead to increased urination, increased water intake, urinary tract infections, kidney damage and dehydration. Elevated blood sugar and decreased insulin levels can significantly damage other tissues of the body, including the brain and central nervous system.
Occasionally diabetes is transient in pets, but this is not typical. In pets the diabetes is usually similar in certain ways to human type 2 diabetes. One specific difference is that most pets that become diabetic are dependant on insulin whereas many humans may control their diabetes with diet and exercise. Without insulin, cats in particular can readily become ketotic. Ketosis is damaging and can be a life threatening condition. Ketosis is a somewhat of a self-perpetuating situation. When insulin and therefore sugar is not available to tissues that need it, fat is released into the bloodstream to allow the liver to convert the fat into sugar. However, without insulin, the fat cannot be converted into the required sugar. So the liver stores the fat, which eventually is overloaded with fat, causing damage in the liver itself. Remember, even if the fat can be converted to sugar, there is already too much sugar in the blood stream, but the cells that cannot access it are starving. Eventually the pet becomes severely ill. They become weak, dehydrated, and nauseous and can have severe organ damage up to and including central nervous system depression, coma and death.
Diagnosis is based on history, clinical signs and lab results. A number of diseases that affect animals appear similar to diabetes. If your pet is diagnosed, or suspected of being diabetic, a number of lab evaluations will be recommended initially to give objective values to your pet's health and ability to recover (if significantly ill) and control the diabetes. Each lab test has its own indication. We will make recommendations based on the information you have given us, your pet's physical exam and screening lab test results.
In addition to blood sugar level, blood chemistries give indication of kidney, liver and pancreatic function or dysfunction. Serum electrolytes, proteins and other values help determine degree of hydration, and chemical imbalance within your pet. A complete blood cell count (CBC) gives information on red and white cells, helping determine if your pet is anemic, or showing signs of infection. A urinalysis further allows us to determine renal function, urinary infections and/or cystitis. A urine culture and sensitivity will determine if there is a urinary tract infection, and which antibiotics the bacteria is sensitive to. This step is important, as diabetics are compromised and more susceptible to infection. The level of glycosylated hemoglobin can help determine the difference between a transient hyperglycemia, and a true diabetic.
Pancreatic disease can make regulation of the diabetic difficult. Evaluation of trypsin-like immunoreactivity (TLI) can detect pancreatitis and/or exocrine pancreatic deficiency.
Depending on your pet's clinical condition, he or she may need to be hospitalized. Many will need IV fluids and supportive care. Severely ill pets may not survive. Others may need several days or longer before home care is recommended. Once diagnosed, and lab evaluation has been completed, the diabetes needs to be controlled. We need to determine what your pet's specific insulin need is. Most pets will require injections of insulin two times daily. Since insulin manufacturers produce insulin that is best for humans, we typically need to use insulin made for humans. Some pets will do well on one of, or a combination of, the common forms, and some will require special order insulin. Luckily, insulin is not very expensive. However, it can be time consuming to determine the best dose for any one pet. We must start out with a low recommended dose, and determine the initial response. Giving too much insulin can cause blood sugar level to drop significantly low. Hypoglycemia can cause weakness, depression, seizures, coma and/or death. Conversely, giving too little insulin for too long can lead to all the problems listed previously.
A blood glucose curve is determined by taking serial blood glucose levels starting with a morning insulin injection and continuing for up to 24 hours. This may need to be done several times, with varying parameters. There are numerous reasons why this is not a perfect system, but it is still a valuable tool. A blood glucose curve gives us three important pieces of information for each dose and type of insulin used: It allows us to assess the effectiveness of the insulin; how low the blood glucose level will drop from the insulin; and how long the insulin has it's effect in the specific pet.
We will teach you how to administer insulin. No one wants to give his or her pet injections. However, you will find that in most pets, it is simple. The needles are tiny. The dose is tiny. Many times, insulin is given when the pet is eating, so they do not even notice what you are doing. I know you still will be hesitant to learn this task. But, my rule' is that you should learn how, and do it for two weeks. Anyone can do something for two weeks, right? If after that you do not feel it is worth your pet's life, we will talk more about your options. (I have never yet had anyone not get use to it during that two-week period of timeJ). We are here to help!!
It is important to understand that the need for insulin can change in any being. So, even when we determine your pet's insulin dose, it may eventually change. But with your at home monitoring of the pet, and our evaluations, we can usually make adjustments without your pet needing further hospitalization.
Some owners can take part in determining their pet's insulin need. We can teach you how to collect a drop of blood from your pet to determine blood sugar level. You can check urine sugar level at home to help. Even just monitoring for appetite, attitude, urine output and thirst is important and helpful. You need to understand that there will be occasions when the blood sugar or urine sugar is higher or lower than desirable. Since blood sugar will change with stress, exercise, diet, and a variety of other reasons, it is important that the dose of insulin is not adjusted without discussing the situation with us first.
Rule-of-Thumb It is better to give less insulin than to give too much. If in doubt about a particular injection, it is better to skip, or to have under dosed a single dose than to give too much.
What about oral hypoglycemics? Drugs such as Glipazide, and similar medications act by increasing insulin secretion However they cannot work if there is not enough functional cells available to make and secrete insulin, which is usually the case with diabetic cats and dogs. Some cats that have been diagnosed with mild signs of diabetes may be a candidate for this medication.
Once your pet is regulated' and you have learned how to properly care for your diabetic pet, we will want to recheck some lab values to be sure your pet is regulated. To determine how well your pet's diabetes is being controlled a blood fructosamine level gives an overall indication for the last 1-3 weeks. If all seems to be doing well, only screening lab work needs to be completed. In other cases more in depth diagnostics may be indicated to rule out other problems and complicating factors.
As mentioned above, owners can take part in determining their pet's insulin need. Keeping a daily diary of date, time and dose of insulin administered, as well as urine sugar level, appetite, attitude, urine output and thirst is important and helpful. You need to understand that there will be occasions when the blood sugar or urine sugar is higher or lower than desirable. We do not change insulin dose in pets unless there is a definite trend of changes over several days time. Since blood sugar will change with stress, exercise, diet, and a variety of other reasons, it is important that the dose of insulin is not adjusted without discussing the situation with us first.
Just as with humans, diet is very important in controlling diabetes. There are a number of foods that are designed and formulated specifically for diabetics. We will make recommendations, but we may need to try several before we find the right food for your pet. In general, it is best to feed the recommended diet, and supplement it only if needed. Additionally, we will recommend when it will be best to feed your pet. In general, for pets that are on 2 times daily insulin injection, it usually best to feed 4 times, morning, middle of the day, evening, and later at night. Pets on one time daily injections should be fed 3 meals, morning, afternoon and one in the evening. However, we will help you determine what will be best for you and your pet. For pets that do not overeat, they may even be allowed to free feed.
Any of the previously mentioned problems can develop with diabetics. Not enough insulin can lead to chronic deterioration including liver disease, urinary tract or kidney disease, cataracts, retinopathy and neuropathy. But these problems develop over time, such as days to weeks. Acute, or more sudden problems can happen if blood sugar drops too low. This can cause weakness, collapse, seizures, coma and death. This can happen within minutes to hours. This hypoglycemia can occur for one of several reasons. Insulin administration without the pet eating, or vomiting the eaten food can cause this. Administration of too much insulin, or repeating the dose mistakenly are common causes of hypoglycemia.
If you suspect you have administered too much insulin, or gave a second dose mistakenly, it would be best to have your pet hospitalized and monitored.
If you see your pet in a weak, collapsed or seizuring state, you should administer 1 teaspoon of Karo syrup on the tongue, or otherwise in the mouth. You should then call the veterinarian to have your pet examine immediately. Even if your pet responds to the administered Karo syrup, it may need more care than you can provide at home. This is particularly so because your pet may have come into this state from being either hypo- (low) or hyper- (high) glycemic.
Other complications with diabetes can arise from other concurrent disease or injury. Dental disease can significantly alter your pet's response to insulin. If your pet has significant dental disease, dental care is recommended. Special care will be taken for diabetics undergoing anesthesia for dental care, or for other reasons. Other infections can similarly cause dysregulation. Metabolic diseases, organ failure, cancer, stress and trauma can all significantly affect your pet and the response to and need for insulin.
If your pet develops cataracts, treatment by a veterinary ophthalmologist is recommended, but can only be completed after your pet is well regulated.
In closing, many pets are diagnosed and treated for diabetes with very little trouble. The more in tune you are with your pet, the more consistent your daily routine is, the healthier your pet is when diagnosed, the easier it will be to control the diabetes without significant complications.