Type 1 Diabetes

In type 1 diabetes there is gradual destruction of the beta cells in the pancreas, happening over a few years (or sometimes over a few months, as happens in infants and toddlers). The cause for the destruction is the body’s own immune system attacking itself (autoimmune disease), and in this case, the insulin-producing beta cells in the pancreas.

There are immune cells that destroy the beta cells and others that produce antibodies that can be detected in a blood test. Type 1 diabetes may also be associated with other autoimmune diseases, most commonly affecting the thyroid gland, that present before, at, or after the diagnosis of type 1 diabetes.

Because of the destruction and lack of insulin, treatment of children with type 1 diabetes relies on giving them back insulin. At present, insulin is given as multiple daily injections with a very thin and short needle or a pump that delivers insulin under the skin through a plastic tube. Other types of insulin, such as inhaled or oral insulin, may in the future replace injections to some degree.


Eventually, after 80 percent or more of the insulin-producing beta cells are destroyed, there is true insulin deficiency, leading to the typical symptoms of diabetes, which usually appear over a short time (weeks), and become progressively worse:

  • Excessive urination (sweet urine, thus diabetes mellitus)
  • Bed-wetting in a child who was previously toilet trained
  • Excessive thirst and/or dry mouth
  • Increased appetite
  • Weight loss, despite overeating
  • Fatigue and weakness
  • Blurred vision that fluctuates (due to changes in blood sugar)
  • Other non-specific complaints are irritability, apathy, decline in school performance and restlessness. Adolescent girls may develop yeast infections.

Children often present during an acute illness, such as diarrhea or a “cold,” in which case the symptoms of diabetes can develop over days. In addition children may become significantly dehydrated. During an infection and stress there is a higher demand from the body to produce insulin, and the load becomes excessive for the small number of remaining beta cells. Children who are diagnosed during an acute illness are often sicker and develop a condition called diabetic ketoacidosis (DKA). Symptoms associated with DKA, such as nausea or vomiting can be confused with “stomach flu,” and the abdominal pains seen in DKA can sometimes lead to a false diagnosis of appendicitis.

What is DKA?

As the body cannot use glucose, fat is broken down and ketone bodies are produced, resulting in acidosis. These can also be detected in the urine. As more ketone bodies are produced and acidosis progresses, it reaches a dangerous condition called ketoacidosis. The child tries to compensate by breathing heavily, and parents may notice their child’s breath smells fruity. Other complaints can be nausea, vomiting or abdominal pains.

If left uncared for, DKA is a life-threatening condition!

Children need to be admitted promptly to a hospital, often to an intensive care unit, that allows close monitoring and support of fluids and electrolyte imbalance, as well as being on the alert for mental status changes. Rady Children’s Hospital offers experienced pediatric endocrinologists well versed in administering continuous insulin drips, and an excellent intensive care setting, to treat this serious condition, which can lead to brain swelling. As in many conditions in pediatrics, prevention is the best strategy. Recognizing the signs and symptoms of diabetes early, can prevent a child from progressing to DKA.

Who Gets Type 1 Diabetes in Childhood?

Most of the time there is no prior family member with type 1 diabetes, although other family members may have another autoimmune condition affecting the thyroid, skin (vitiligo) or other organs.

Diabetes is NOT contagious!

  • There is a 1 in 20 chance of another family member getting type 1 diabetes.
  • If a first-degree relative of a child has type 1 diabetes, there is a 1 in 10 risk for that child to develop type 1 diabetes.
  • If one twin has type 1 diabetes, there is a 50% or greater chance that his identical twins will develop it later in life, sometimes only as an adult.

What to Expect

If your child is diagnosed with type 1 diabetes, he/she will be seen in our Diabetes Clinic one to two weeks after being discharged from the hospital.


Written by Rady Children’s Division of Endocrinology/Diabetes