Diabetes Mellitus
Diabetes mellitus is a disorder in which blood sugar (glucose) levels are abnormally high because the body does not produce enough insulin.
The symptoms, diagnosis, and treatment of diabetes are similar in children and adults (see Section 13, Chapter 165). However, treatment of diabetes in children may be more complex and must be tailored to the child's physical and emotional maturity level.
Insulin is a hormone released by the pancreas that controls the amount of sugar in the blood. A child with diabetes has high blood sugar levels either because the pancreas produces little or no insulin (type 1 diabetes, formerly called juvenile-onset diabetes) or because the body is insensitive to the amount of insulin that is produced (type 2 diabetes). In either case, the amount of insulin available is insufficient for the body's needs.
Type 1 diabetes occurs throughout childhood, even in infancy, with a usual age of onset between 6 and 13 years. Type 2 diabetes occurs mainly in adolescents.
Up until the 1990s, more than 95% of children who developed diabetes had type 1, usually as a result of an attack by the immune system on the cells in the pancreas that make insulin (islet cells). Recently, the number of children, especially adolescents, with type 2 diabetes has been steadily increasing. Today, 10 to 40% of children newly diagnosed with diabetes have type 2. The increase in childhood type 2 diabetes has been particularly prominent among Native Americans, blacks, and Hispanics. Obesity and a family history of type 2 diabetes are major factors in the development of type 2 diabetes (but not type 1).
 See the sidebar Which Children Are at Risk for Type 2 Diabetes?
Symptoms
High blood sugar levels are responsible for a variety of immediate symptoms and long-term complications.
Symptoms develop quickly in type 1 diabetes, usually over 2 to 3 weeks or less, and tend to be quite obvious. High blood sugar levels cause the child to urinate excessively. This fluid loss causes an increase in thirst and the consumption of fluids. Some children become dehydrated, resulting in weakness, lethargy, and a rapid pulse. Vision may become blurred.
Diabetic ketoacidosis occurs at the beginning of the disease in about one third of children with type 1 diabetes. Without insulin, cells cannot use the sugar that is in the blood. Cells switch to a back-up mechanism to obtain energy and break down fat, producing compounds called ketones as byproducts. Ketones make the blood too acidic (ketoacidosis), causing nausea, vomiting, fatigue, and abdominal pain. The ketones make the child's breath smell like nail polish remover. Breathing becomes deep and rapid as the body attempts to correct the blood's acidity (see Section 12, Chapter 159). The increase of ketones in the blood leads to diabetic ketoacidosis. Diabetic ketoacidosis can progress to coma and death, sometimes within a few hours. Children with ketoacidosis often have other chemical imbalances in the blood, such as an abnormal level of potassium and high levels of lipids (fats).
Symptoms in children with type 2 diabetes are milder than those in type 1 and develop more slowly--over weeks or even a few months. Parents may notice an increase in the child's thirst and urination or only vague symptoms, such as fatigue. Typically, children with type 2 diabetes do not develop ketoacidosis or severe dehydration.
Diagnosis
Doctors suspect diabetes when children have typical symptoms or when a urine test done during a routine physical examination reveals sugar. The diagnosis is confirmed by measurement of the blood sugar level. Preferably, the blood test is done after fasting overnight. A child is considered to have diabetes if the fasting blood sugar level is 126 milligrams per deciliter (mg/dL) or higher. Rarely, doctors order a blood test that detects antibodies to islet cells to help distinguish type 1 diabetes from type 2; however, this information is rarely useful.
Because prompt measures (such as dietary changes, an increase in physical activity, and weight loss) may help prevent or delay the onset of type 2 diabetes, children at risk should be screened with a blood test. Nothing can be done to prevent type 1 diabetes.
Treatment
The main goal of treatment is to keep blood sugar levels as close to the normal range as can be done safely. To control blood sugar, children with diabetes take drugs (such as insulin or drugs given by mouth) and change their lifestyle. Changes include adjustments in diet, regular exercise, and, for overweight children, weight loss.
When type 1 diabetes is first diagnosed, children are usually hospitalized. Children with diabetic ketoacidosis are treated in an intensive care unit. Children with type 1 diabetes always require insulin because nothing else is effective. They typically receive two or more daily injections of insulin, although a few may receive insulin continuously delivered under the skin by a pump. Insulin treatment is usually begun in the hospital so that blood sugar levels can be tested often and doctors can change insulin dosage in response. Rarely, treatment is started at home.
Children with type 2 diabetes do not usually need to receive treatment in the hospital. They do require treatment with diabetic drugs taken by mouth. The drugs used for adults with type 2 diabetes (see Section 13, Chapter 165) are safe for children, although some of the side effects--particularly diarrhea--cause more problems in children. Some children with type 2 diabetes need insulin. A few children who lose weight, improve their diet, and exercise regularly may be able to stop taking the drugs.
Nutritional management and education are particularly important for all children with diabetes. Because carbohydrates in food are turned into glucose by the body, variations in carbohydrate intake cause variations in blood sugar levels. Thus, children with diabetes need to eat meals on a regular schedule; long periods between eating should be avoided because blood sugar may fall too low. Large amounts of sugar, such as soda, candy, and pastries, are discouraged because blood sugar may rise too high. Parents and older children are taught how to gauge the carbohydrate content of food and adjust what children eat as needed to maintain a consistent daily intake of carbohydrates. Children of all ages find it difficult to consistently follow a properly balanced meal plan (consumed at regular intervals) and avoid the temptations of sugary snacks. Infants and preschool-aged children present a particular challenge to parents because of the concern arising from the dangers of frequent and severe low blood sugar (hypoglycemia).
Emotional issues affect children with diabetes and their families. The realization that they have a lifelong condition may cause some children to become sad, angry, and sometimes even deny that they have an illness. A doctor needs to address these emotions to secure the child's cooperation in complying with the required regimen of meal plan, physical activity, blood glucose testing, and drugs. Failure to resolve these issues can lead to difficulties with glucose control.
Summer camps for children with diabetes allow these children to share their experiences with one another while learning how to become personally more responsible for their condition.
If treating the diabetes is difficult, the doctor may enlist the aid of a team of other professionals, possibly including a pediatric endocrinologist, dietitian, diabetes educator, social worker, or psychologist. Family support groups may also help. The doctor may provide parents with information to bring to school so that school personnel understand their roles.
Monitoring Treatment: Children and parents are taught to monitor the blood sugar level at least 4 times a day using a blood sample obtained by pricking a fingertip or the forearm with a small implement called a lancet. Once experience is gained, parents and many children can adjust the insulin dose as needed to achieve the best control. In general, by 10 years of age, children start to become interested in testing their blood sugar levels and injecting insulin themselves. Parents should encourage this independence but make sure the child is being responsible. Doctors teach most children how to adjust their insulin dosage in accordance with the patterns of their home blood glucose records.
Children with diabetes typically see their doctor 4 times a year. The doctor evaluates their growth and development, reviews blood sugar records that the family member keeps, provides guidance and counseling about nutrition, and measures glycosylated hemoglobin (hemoglobin A1c)--a substance in the blood that reflects blood glucose levels over the long term. The doctor screens for long-term complications (see Section 13, Chapter 165) once a year by measuring protein in the urine, assessing function of the thyroid gland, and performing neurologic and eye examinations.
Some children with diabetes do very well and control their diabetes without undue effort or conflict. In others, diabetes becomes a constant source of stress within the family, and control of the condition deteriorates. Adolescents in particular often find it difficult to follow the proper treatment routine given the demands on their schedule and the limitations on their freedom that arise from diabetes. An adolescent benefits if the doctor considers the adolescent's desired schedule and activities and takes a flexible approach to problem solving--working with the adolescent rather than imposing solutions.
Complications of Treatment and Illness: No treatment completely maintains blood sugar at normal levels. The goal of treatment is to avoid blood sugar levels that are too high and too low. The complications of diabetes include heart disease, kidney failure, blindness, peripheral vascular disease, and other serious disorders. Although these events take years to develop, the better the control of diabetes, the less likely that complications will ever occur.
Low blood sugar (hypoglycemia (see Section 13, Chapter 166)) occurs when too much insulin or diabetic drugs are taken or when the child does not eat regularly. Hypoglycemia produces weakness, confusion, and even coma. In adults, adolescents, and older children, episodes of hypoglycemia rarely cause long-term problems. However, frequent episodes of hypoglycemia in children younger than 5 may permanently impair intellectual development. Young children also may not be aware of the warning symptoms of hypoglycemia. To minimize the possibility of hypoglycemia, doctors and parents monitor young children with diabetes particularly closely and also use a slightly higher target range for their blood sugar level.
Children and adolescents with type 1 diabetes who miss insulin injections may develop diabetic ketoacidosis within days. The long-term insufficient or inadequate use of insulin can lead to a syndrome of stunted growth, delayed puberty, and an enlarged liver (Mauriac syndrome).
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