Juvenile Diabetes

Introduction
Signs and Symptoms
Causes
Risk Factors
Screening and Diagnosis
Treatment
Prevention

The signs and symptoms of type 1 diabetes often appear after a flu-like illness and gradually intensify over the course of a few weeks. Typical features may include:

Increased thirst and frequent urination. With type 1 diabetes, excess sugar (glucose) builds up in your bloodstream. A high level of blood glucose pulls water from your body's tissues, making you thirsty. As a result, you drink more fluids and urinate more. The excess sugar in your bloodstream passes through your kidneys and leaves your body in your urine.

Extreme hunger. The basic defect in type 1 diabetes - an inability to produce insulin, the hormone necessary for glucose to enter cells and fuel their functions - leaves your muscles and organs energy depleted. That triggers intense hunger. Eating fills your stomach, but the hunger persists because, without insulin, the glucose produced from dietary carbohydrates never reaches your body's energy-starved tissues.

Weight loss. Despite eating a lot to relieve their constant hunger, people with type 1 diabetes lose weight, sometimes rapidly. That's because the body's cells are deprived of glucose and energy as glucose is lost into the urine. Without the energy glucose supplies, cells die at an increased rate before they can divide and replace themselves. Muscle tissues and fat stores shrink, and body weight declines.

Blurred vision. A high level of blood glucose pulls fluid from all your tissues, including the lenses of your eyes. The decrease in fluid affects your ability to focus.

Fatigue. When your cells are deprived of glucose, you become tired and irritable.

In type 1 diabetes, the body has little or no insulin because the immune system - which normally fights harmful bacteria or viruses - has attacked and destroyed the insulin-producing cells in the pancreas, a gland located just behind the stomach. Similar immune system attacks on different body tissues occur in a number of other diseases, which are known as autoimmune diseases. Such diseases include multiple sclerosis, in which the immune system attacks the substance that coats nerve fibers, and rheumatoid arthritis, in which the immune system attacks the linings of the joints.

Researchers believe that factors such as genetics, diet and exposure to certain viruses all may be involved in triggering different autoimmune diseases, including type 1 diabetes. Because type 1 diabetes typically appears in the wake of an infection, the immune attack on insulin-producing cells may be a consequence of the immune system's reaction to the earlier infection.

Lack of insulin results in diabetes because of the vital role insulin plays in making glucose - the body's fuel - available to cells. During digestion, your body transforms the carbohydrates from such foods as bread, fruits and milk products into different types of sugar molecules. One of these sugar molecules is glucose, the main energy source for your body. Glucose is absorbed directly into your bloodstream after you eat, but it can't enter your cells without the help of insulin.

Normally, your pancreas produces insulin continuously, raising its output in response to the increase in blood sugar that occurs after you eat. This extra insulin "unlocks" your cells so that more sugar can enter, providing your body with energy as well as maintaining a normal level of sugar in your blood.

Your liver also plays a key role in maintaining a normal blood sugar level. If you have more glucose than your cells need for energy, your body can remove the excess glucose from your bloodstream and store it in your liver as glycogen - a form of stored glucose. Then, when you run low on glucose - if you haven't eaten for a while, say - your body can tap into the stored glucose and release it into your bloodstream.

When your pancreas functions normally, your blood glucose fluctuates in response to exercise, stress, infections, food and a variety of other factors. But your hormonal system - including but not limited to the insulin-producing pancreas - continuously makes complex adjustments that keep your blood sugar levels within set limits.

Although the exact cause of type 1 diabetes is unknown, some characteristics increase the risk. These factors include:

• Family history. Your chance of developing type 1 diabetes increases if you have a parent or sibling with the disease.
  
• Race. Type 1 diabetes is more common in white Americans and in European countries such as Finland and Sweden.

Parents of children with type 1 diabetes typically find out about the disease when signs and symptoms, such as fatigue, thirst, frequent urination and weight loss, become too severe to overlook. Older children and adults who develop type 1 diabetes may notice the signs and symptoms earlier than do small children, who can quickly become very ill and lose consciousness from the effects of high blood sugar. In these instances, doctors take steps to normalize vital signs and blood glucose before further testing to confirm the presence of type 1 diabetes.

Any time signs, symptoms and physical examination suggest type 1 diabetes, blood glucose testing is an essential step. Simple blood tests can rule out diabetes quite reliably. But in the absence of severe diabetes signs and symptoms, a screening test may find that your or your child's blood sugar is higher than normal. When that happens, further testing is necessary to diagnose type 1 diabetes. From general to specific, blood tests for diabetes include:

• Random blood sugar test. This test is part of the blood work routinely performed as part of a physical exam. It involves having blood drawn from a vein in your arm. If you have eaten just before this test, your blood sugar may be high. Even so, it shouldn't be higher than 200 milligrams per deciliter (mg/dL). If it is, you have diabetes.
  
• Fasting blood glucose test. In general, your blood sugar is highest right after you eat and lowest after an overnight fast. That's why the preferred way to test your blood sugar is to take a blood sample from a vein in your arm after you've fasted overnight or for at least eight hours. If your fasting blood sugar measures 126 mg/dL or higher, your doctor may repeat the test. If the results of the second test are the same, you likely will receive a diagnosis of diabetes.

After you've received a diagnosis of diabetes, your doctor may order another blood test to measure your average blood glucose level for the previous two to three months. The test, known as a glycated hemoglobin or hemoglobin A1C test, measures the amount of blood sugar attached to hemoglobin molecules - the iron-rich molecules in red blood cells that deliver oxygen to your body. The higher your blood sugar levels, the more hemoglobin molecules you will have with sugar attached. In general, the life cycle of a red blood cell is 75 to 90 days, which is why the A1C test shows your average blood glucose levels for the past two to three months. Although normal laboratory ranges for hemoglobin A1C vary, your doctor will desire levels less than 7 percent.

Regular hemoglobin A1C testing is vital to long-term diabetes management. More than repeated daily blood sugar tests do, hemoglobin A1C indicates how well your treatment plan is working. Elevated hemoglobin A1C may mean you need to adjust your insulin regimen or meal plan - possibly because you haven't learned to fine-tune your eating habits, or perhaps because you should be taking more insulin.

Treatment is a life-long commitment in type 1 diabetes. The ongoing goal is to keep your blood sugar levels as close to normal as possible. By controlling your blood sugar, you can avoid short-term complications and delay or prevent long-term complications. In fact, research shows that tight control of blood sugar levels can reduce the risk of diabetes-related heart attacks and strokes by more than 50 percent.

You'll work closely with your diabetes care team - doctor, nurse, dietitian and diabetes educator - to balance your insulin intake with your diabetes meal plan and activity level.

Blood sugar monitoring
If you've just received a diagnosis of type 1 diabetes, monitoring your blood sugar may seem like an overwhelming task. But once you learn to measure your blood sugar and understand how important it is, you'll feel more comfortable with the procedure and better able to manage your disease. You'll test your blood sugar at least twice a day. Depending on what type of insulin therapy you select or require - single dose injections, multiple dose injections or insulin pump - you may establish a pattern of testing four times each day, or even more often.

Testing is crucial because it tells you whether you're keeping glucose levels within your target range. Your doctor sets this target range based on your age, the presence of diabetes-related complications or other medical conditions, and your ability to recognize signs and symptoms of hypoglycemia soon enough to eat something sugary before you have serious symptoms. The ideal target range before meals is 90 to 130 mg/dL. Two hours after a meal, your blood sugar should be below 180 mg/dL.

When you have type 1 diabetes, the timing of your insulin injections and the type of insulin used have dramatic effects on your blood sugar. But even if you take insulin and eat on a very rigid schedule, the amount of sugar in your blood can change unpredictably. Self-monitoring - testing your blood sugar and keeping a record of the results - helps you understand the factors that affect your blood sugar, so you can learn to make adjustments in your treatment. You'll learn from experience how your blood sugar changes in response to:

• Food. Food raises your blood sugar level. Blood sugar is highest one to two hours after a meal. What and how much you eat, and the time of day, also affect your blood sugar level.
• Exercise and physical activity. In general, the more active you are, the lower your blood sugar. Physical activity moves sugar from your bloodstream into your cells. Aerobic exercises such as brisk walking, jogging or biking are especially good for reducing blood sugar. Because aerobic exercise is so effective at lowering blood sugar, your health care team will help you figure out how to adjust your insulin dose before you exercise so that your levels don't fall too low.
• Medications. You take insulin to lower your blood sugar. In fact, insulin is the basis for all the other aspects of type 1 diabetes treatment. But medications you take for other conditions may affect your blood glucose levels as well, sometimes making it necessary to alter your diabetes treatment plan. Among the drugs most likely to increase blood glucose are corticosteroids, used to treat asthma and many other types of inflammation, and thiazides, which are often the first line of treatment for high blood pressure.
• Illness. The physical stress of a cold or other illness causes your body to produce hormones that raise your blood sugar level. The additional sugar helps promote healing. But if you have diabetes, more sugar can be a problem. In addition, a fever increases your metabolism, speeding your cells' utilization of insulin. As a result, you may need to take more or larger doses of insulin when you're running a fever.   Whatever your symptoms, it's important to monitor your glucose levels frequently when you're sick.
• Alcohol. Even a small amount of alcohol - about 2 ounces - can cause your sugar levels to fall too low. If you choose to drink, do so only in moderation. And monitor your blood sugar before and after consuming alcohol to see how it affects you. Also, keep in mind that alcohol counts as carbohydrate calories in your diet.
• Fluctuations in hormone levels. The female hormone estrogen typically makes cells more responsive to insulin, and progesterone makes cells more resistant. Although these two hormones fluctuate throughout the menstrual cycle, the majority of women don't notice a corresponding change in blood sugar levels. Those who do are more likely to experience changes in blood sugar during the third week of their menstrual cycle, when estrogen and progesterone levels are highest.

  Hormone levels also fluctuate during perimenopause - generally defined as the two to eight years leading up to menopause, plus the first year after your final period. How this affects blood sugar varies, but most women can control any symptoms with additional exercise and changes in their diet. If your symptoms are more severe, your doctor may recommend oral contraceptives or hormone replacement therapy (HRT).

A healthy diet
Contrary to popular perception, there's no diabetes diet. Furthermore, having diabetes doesn't mean you have to eat only bland, boring foods. Instead, it means you'll eat more fruits, vegetables and whole grains - foods that are high in nutrition and low in fat and calories - and fewer animal products and sweets. Actually, it's the same eating plan everyone should follow.

Yet understanding what and how much to eat can be a challenge. Fortunately, a registered dietitian can help you put together a meal plan that fits your health goals, food preferences and lifestyle. Your dietitian may recommend that you develop your meal plan by using the dietary exchange system, by carbohydrate counting or by following a glycemic-index diet.

Once you've decided on a meal plan, keep in mind that consistency is extremely important. To keep your blood sugar on an even keel, try to eat the same amount of food with the same proportion of carbohydrates, proteins and fats at the same time every day.

Medications
All people with type 1 diabetes must take insulin to survive. Unfortunately, insulin can't be taken by mouth because enzymes in your stomach make it ineffective. Instead, you inject your insulin under your skin using a very fine needle and syringe or an insulin pen injector - a device that looks like an ink pen, except the cartridge is filled with insulin.

An insulin pump is a pumping device about the size of a deck of cards. You wear it outside your body. A small tube connects the reservoir of insulin to a catheter that's inserted under the skin of your abdomen. The pump dispenses the desired amount of insulin into your body and can be adjusted to infuse more or less insulin depending on meals, activity and glucose level. Insulin pumps aren't for everyone. But for some people they provide improved blood sugar control and a more flexible lifestyle.

The most widely used form of insulin is synthetic human insulin, which is chemically identical to human insulin but manufactured in a laboratory. Unfortunately, synthetic human insulin isn't perfect. One of its chief failings is that it doesn't mimic the way natural insulin is secreted. But newer types of insulin, known as insulin analogs, more closely resemble the way natural insulin acts in your body. Among these are lispro (Humalog), insulin aspart (NovoLog) and glargine (Lantus).

Pramlintide (Symlin), recently approved by the Food and Drug Administration for type 1 and type 2 diabetes, curbs the sharp increase in blood sugar that occurs after meals. Taken as an injection before you eat, pramlintide slows the movement of food through your stomach.

Exercise
Everyone needs regular aerobic exercise, and people with type 1 diabetes are no exception. The good news is that the same exercises that protect your heart also help lower your blood sugar levels.

See your doctor before beginning any exercise program. Once you have the go-ahead, take some time to think about which activities you enjoy and are likely to stick with. Walking, hiking, jogging, biking, tennis, cross-country skiing and swimming are all good choices.

Aim for at least 30 minutes of aerobic exercise most days. But if you haven't been active for a while, start slowly and build up gradually. For the best results, combine your aerobic activity with stretching and strength training exercises.

Transplantation
In recent years, scientists have focused increasing attention on transplantation for people with type 1 diabetes. Current procedures include:

• Pancreas transplant. With a successful pancreas transplant, many people with diabetes no longer need to use insulin. Unfortunately, pancreas transplants aren't always successful. In addition, your body may reject the new organ days or even years after the transplant, which means you'll need to take immunosuppressive drugs the rest of your life. These drugs are costly and can have serious side effects, including a high risk of infection and organ injury. Because the side effects can be more dangerous to your health than your diabetes, you're usually not considered a candidate for transplantation unless your diabetes can't be controlled or you're experiencing serious complications.

  Most pancreas transplants are done in conjunction with or after a kidney transplant. Kidney failure is one of the most common complications of diabetes, and receiving a new pancreas when you receive a new kidney may actually improve kidney survival.

  Since there aren't enough cadaver pancreases, you might choose to receive a partial pancreas transplant from a living donor who matches your tissue type. If you're receiving a kidney from a living donor, you may receive a partial pancreas transplant from the same donor at the same time.

• Islet cell transplantation. The islet cells in the pancreas are the target of the misdirected immune system reaction responsible for type 1 diabetes. As a result, insulin producing beta cells, which make up the bulk of islet cells, also are destroyed. To help the body begin making insulin again - and possibly provide a cure for type 1 diabetes - researchers have found a way to transplant new islet cells into the liver. This experimental procedure is costly and has met with problems in the past. Still, new surgical techniques and better drugs to prevent islet cell rejection are showing promise.