DIAGNOSING DIABETES IN CHILDREN AND YOUTH

The symptoms of diabetes in children, youth, and adults are similar. However, as the American Diabetes Association (ADA) has pointed out, children are not “little adults,” and diabetes in children has its own unique pathophysiology and development issues that require care and interventions tailored to meet those needs (ADA, 2018a).

Diagnosing Type 1 Diabetes

Type 1 diabetes was previously known as juvenile diabetes, since it was believed that this form of diabetes occurred only in children. However, when it became clear that this form of diabetes can occur across the lifespan, the terminology was changed to type 1 diabetes. However, there is ongoing debate over whether the terms type 1 and type 2 fully encapsulate the characteristics of both forms of diabetes and clearly differentiate between them (Hoskins, 2020).

Type 1 diabetes is a complex disease. Autoimmune destruction of the insulin-producing beta cells in the pancreas results in complete insulin deficiency or the production of minute amounts of insulin that are insufficient to meet the needs of the body. It is theorized that viral infections have a role in initiating the autoimmune response in genetically at-risk persons that results in the destruction of beta cells and the consequent development of T1D (Tamborlane, 2021).

Type 1 diabetes is considered to have both a genetic and environmental component, although a family history of the condition is frequently not found at the time of diagnosis. However, the presence of a family history of other autoimmune conditions such as Grave’s disease or Hashimoto’s thyroiditis has been noted at the time of diagnosis of T1D. Research studies based on twin and family data suggest that in monozygotic twins (twins who share 100% of their genes), when one of the twins has T1D, the risk of the other twin developing the disease is around 50%.

The most frequent period of onset of T1D is during childhood. Childhood onset of the disease is postulated to be more probably genetic in origin than when the disease develops in later adult years. However, more research is needed to fully understand the genetic impact related to the development of T1D (NIDDK, 2018).

T1D can be diagnosed at any age, but for children, the two peak periods are from the ages of 5–6 years and 11–13 years. The initial signs and symptoms of T1D can include:

• Thirst
• Increased urination
• Onset of bedwetting in children who have already gained continence
• Increased appetite
• Weight loss
  (AAP, 2020; Basina, 2020)

In around one third of children, the first presenting sign of T1D is diabetic ketoacidosis (ADA, 2020a) (see also “Diabetic Ketoacidosis” later in this course).

Missed diagnosis for T1D in children is common. Many times, when a child is brought to the pediatrician’s office with listlessness, weight loss, increased thirst, nausea, and possible vomiting, the initial diagnosis may be “stomach flu.” It is important to be aware that these flu-like symptoms are also the symptoms of T1D.

Further assessment at this point can include either a simple finger-stick blood glucose test or a ketone stick test of the patient’s urine. These tests in themselves do not confirm a diagnosis of T1D, but positive results may indicate the need for further testing. For example, a random blood glucose test that shows a blood glucose level of 200 mg/dL or higher is highly suggestive of diabetes and will require more detailed investigation (Whittemore et al., 2018; Mayo Clinic, 2020).

Beyond a random blood glucose test, diagnostic testing for T1D includes a glycated hemoglobin (A1C) test. An A1C of 6.5% or greater on two separate tests is indicative of T1D. A fasting blood glucose test may also be done after the child has fasted overnight, with a level of 126 mg/dL or greater supporting a diagnosis of T1D (Mayo Clinic, 2020).

At the time of diagnosis of T1D, approximately 25% of children have thyroid auto-antibodies, which is an indicator of thyroid malfunction, most frequently hypothyroidism. Therefore, once a diagnosis of TID has been confirmed, the child should also be screened for autoimmune thyroid disease. If the first test shows a “slightly abnormal” result, it is recommended to repeat the test once the child’s glycemic targets have been met and are maintained (ADA, 2020a).

Celiac disease is also more common in those with T1D than in the general population. The ADA recommends the following screening protocol for children with TID:

• Soon after the diagnosis of TID is established, screen for celiac disease by assessing IgA tissue transglutaminase (tTG) antibodies.
• Repeat the screening test within 2 years of the T1D diagnosis and again after 5 years.
• For children exhibiting symptoms of celiac disease or who have a first-degree relative with the condition, screen more frequently.

Patients who have a biopsy-confirmed diagnosis of celiac disease are started on a gluten-free diet and will benefit from a referral to a dietitian experienced in diabetes and celiac disease (ADA, 2020a).

Diagnosing Type 2 Diabetes

In type 2 diabetes there is a relative, rather than complete, lack of insulin due to the body not secreting enough insulin or not using insulin well (i.e., insulin resistance). Like T1D, T2D has genetic and environmental components. Several genes have been linked to the development of T2D, but their precise role in the development of the disease has yet to be determined. Studies indicate that high numbers of those diagnosed with type 2 diabetes have a first- or second-degree relative with the condition, with figures ranging from 74% to 100%. Of the environmental components associated with T2D, the most significant is obesity (Tamborlane, 2021).

Approximately 40% of children with T2D have no obvious symptoms, and the condition is often diagnosed during routine physical examinations. The ADA recommends screening for prediabetes and T2D in children and adolescents who:

• Are overweight or obese
• Have a first- or second-degree relative with T2D
• Identify as Native American, African American, Latino, Asian American, or Pacific Islander
• Exhibit signs of insulin resistance or have disorders related to insulin resistance, such as acanthosis nigricans (dark discoloration and thickness of skin in skin folds and creases), hypertension, dyslipidemia, or polycystic ovary syndrome
  (ADA, 2020a)

T2D in children and youth is associated with obesity. Obesity is increasingly diagnosed in children and adolescents (FDA, 2018). Data from 2015–2016 indicate that almost 1 in every 5 youth (18.5%) between the ages of 2 and 19 years is obese (Hales et al., 2017). Exams of children who are overweight should include questions about the following signs and symptoms:

• Thirst
• Frequent urination
• Tiredness
• Blurred vision
• Frequent infections
  (Mayo Clinic, 2017)

While conceding that there is minimal data to support using A1C measurement to diagnosis T2D in children and adolescents, the ADA continues to recommend using A1C as the diagnostic criteria in this group (ADA, 2020a).