Definition of Diabetes in Children
Diabetes mellitus in children is defined as a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both, with diagnostic criteria including a random plasma glucose ≥200 mg/dL with classic symptoms, fasting plasma glucose ≥126 mg/dL, 2-hour plasma glucose ≥200 mg/dL during an oral glucose tolerance test, or HbA1c ≥6.5%. 1, 2
Diagnostic Criteria
The American Diabetes Association establishes the following criteria for diagnosing diabetes in children:
Classic symptoms of hyperglycemia plus random plasma glucose ≥200 mg/dL (11.1 mmol/L) - This requires no further confirmation and necessitates immediate diagnosis and treatment 1, 2
Fasting plasma glucose (FPG) ≥126 mg/dL (7.0 mmol/L) - Fasting is defined as no caloric intake for at least 8 hours 1
2-hour plasma glucose ≥200 mg/dL (11.1 mmol/L) during an oral glucose tolerance test (OGTT) - The test should be performed using a glucose load containing the equivalent of 1.75 g/kg up to a maximum of 75 g anhydrous glucose dissolved in water 1
HbA1c ≥6.5% (48 mmol/mol) - The test should be performed in a laboratory using a method that is NGSP certified and standardized 1
For criteria 2-4, in the absence of unequivocal hyperglycemia, results should be confirmed by repeat testing on a different day 1, 2.
Types of Diabetes in Children
Type 1 Diabetes
- Characterized by autoimmune destruction of β-cells leading to absolute insulin deficiency 1
- Staging system for type 1 diabetes 1:
- Stage 1: ≥2 autoantibodies with normoglycemia (presymptomatic)
- Stage 2: ≥2 autoantibodies with dysglycemia (presymptomatic)
- Stage 3: Symptomatic disease with insulin deficiency
Type 2 Diabetes
- Ranges from predominantly insulin resistance with relative insulin deficiency to predominantly secretory defect with insulin resistance 1
- Typically occurs in overweight/obese children (85% of cases) 1
- Usually diagnosed after age 10 and during middle to late puberty 1
- Strong family history component (74-100% have first or second-degree relatives with type 2 diabetes) 1
Other Specific Types
- Monogenic diabetes (MODY) - genetic defects of β-cell function
- Genetic defects in insulin action
- Diseases of the exocrine pancreas
- Endocrinopathies
- Drug or chemical-induced diabetes
- Infections
- Other genetic syndromes associated with diabetes 1
Clinical Presentation
Children with diabetes typically present with:
- Polyuria (excessive urination)
- Polydipsia (excessive thirst)
- Weight loss
- Polyphagia (excessive hunger)
- Fatigue
- Blurred vision 1, 2
These symptoms typically occur for several days to a few weeks prior to diagnosis in type 1 diabetes 1.
Diagnostic Pitfalls to Avoid
Delaying diagnosis and treatment - The metabolic state of untreated children with type 1 diabetes can deteriorate rapidly, requiring immediate diagnosis and insulin therapy 1, 2
Misinterpreting stress hyperglycemia - Incidental hyperglycemia during acute illness doesn't necessarily indicate diabetes but may warrant follow-up, especially with autoimmune markers 1, 2
Overlooking type 1 diabetes in overweight children - Obesity doesn't preclude a type 1 diabetes diagnosis 2
Relying solely on glucose meters for diagnosis - While useful for screening, confirmation with venous plasma glucose measurement in a clinical laboratory is necessary 1, 2
Failing to consider autoimmune comorbidities - Children with type 1 diabetes should be evaluated for other autoimmune conditions, particularly thyroid disease 2
Special Considerations
- Puberty plays a significant role in the development of type 2 diabetes due to increased insulin resistance during this period 1
- Insulin-mediated glucose disposal is approximately 30% lower in adolescents during Tanner stages II-IV compared to prepubertal children or young adults 1
- Growth hormone is likely responsible for insulin resistance during puberty 1
Early diagnosis and appropriate management are crucial to prevent complications and improve outcomes in children with diabetes.