NCLEX Review Guide: Diabetes Mellitus in Children

Type 1 Diabetes Mellitus

• Type 1 Diabetes Mellitus (T1DM) is an autoimmune disorder characterized by destruction of pancreatic beta cells resulting in absolute insulin deficiency. In children, the onset is typically more rapid and severe than in adults, with approximately 85% of all newly diagnosed diabetes in children under 20 being Type 1.
• The etiology involves genetic predisposition (HLA-DR3/DR4) and environmental triggers that lead to autoimmune destruction of insulin-producing cells. The autoimmune process may be present for months to years before clinical manifestations appear, with symptoms typically emerging after 80-90% of beta cells are destroyed.

Type 2 Diabetes Mellitus

• Type 2 Diabetes Mellitus (T2DM) in children is characterized by insulin resistance and relative insulin deficiency, rather than absolute insulin deficiency. The incidence has dramatically increased in recent decades, correlating with childhood obesity rates and now accounts for approximately 10-20% of new-onset diabetes in children and adolescents.
• Risk factors include obesity, sedentary lifestyle, family history, ethnicity (higher in Hispanic, African American, Native American populations), and conditions like polycystic ovarian syndrome. Children with T2DM often present with less dramatic symptoms than those with T1DM and may be asymptomatic at diagnosis.

Classic Symptoms

• The classic triad of diabetes symptoms includes polyuria (frequent urination), polydipsia (excessive thirst), and polyphagia (increased hunger). Children with T1DM typically present with these symptoms plus weight loss over a period of weeks, while children with T2DM may have more gradual onset or be asymptomatic.
• Additional symptoms include fatigue, blurred vision, recurrent infections (especially skin and urinary tract), and delayed wound healing. Young children may present with nocturnal enuresis (bedwetting) after previously being toilet-trained, which results from the polyuria associated with hyperglycemia.

Diagnostic Criteria

• Diagnostic criteria for diabetes in children include: fasting plasma glucose ≥126 mg/dL (7.0 mmol/L), 2-hour plasma glucose ≥200 mg/dL (11.1 mmol/L) during an oral glucose tolerance test, random plasma glucose ≥200 mg/dL with symptoms, or HbA1c ≥6.5%. Any one of these criteria confirms the diagnosis if repeated on a subsequent day.
• Additional laboratory findings typically include glycosuria and, in T1DM, the presence of autoantibodies (islet cell antibodies, insulin autoantibodies, GAD65, IA-2, ZnT8). C-peptide levels are typically low or undetectable in T1DM but normal or elevated in early T2DM.

Diabetic Ketoacidosis (DKA)

• Diabetic Ketoacidosis (DKA) is characterized by the triad of hyperglycemia (blood glucose >250 mg/dL), ketosis, and metabolic acidosis (pH <7.3, bicarbonate <15 mEq/L). It results from absolute or relative insulin deficiency leading to increased gluconeogenesis, glycogenolysis, and ketogenesis.
• Clinical manifestations include dehydration, Kussmaul respirations (deep, rapid breathing), fruity breath odor (from ketones), abdominal pain, nausea/vomiting, altered mental status, and potentially coma. DKA is more common in children with T1DM and can be the initial presentation in 25-40% of new cases.

DKA Management

1. Establish IV access and begin fluid resuscitation with isotonic saline (10-20 mL/kg in first 1-2 hours)
2. After initial fluid bolus, continue IV fluids with added potassium once urine output is established
3. Initiate insulin therapy with continuous IV insulin infusion at 0.05-0.1 units/kg/hour
4. Monitor blood glucose hourly; when glucose reaches 200-250 mg/dL, add dextrose to IV fluids
5. Monitor electrolytes, especially potassium, phosphate, and calcium every 2-4 hours
6. Assess neurological status frequently for signs of cerebral edema
7. Transition to subcutaneous insulin when acidosis resolves and child can eat

Hypoglycemia

• Hypoglycemia in diabetic children is defined as blood glucose <70 mg/dL and is typically caused by excess insulin, insufficient carbohydrate intake, or increased physical activity without appropriate insulin adjustment. Severe hypoglycemia (blood glucose <54 mg/dL) can lead to seizures, loss of consciousness, and if prolonged, brain damage.
• Symptoms include shakiness, sweating, tachycardia, hunger, pallor, behavior changes, confusion, and drowsiness. Young children may not recognize or verbalize symptoms, making them particularly vulnerable. Nighttime hypoglycemia is especially dangerous as symptoms may not wake the child.

Insulin Therapy

• Children with T1DM require lifelong insulin replacement, typically through multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII, insulin pump). The insulin regimen usually consists of basal insulin (long-acting) plus bolus insulin (rapid-acting) for meals and corrections, with total daily dosage ranging from 0.5-1.0 units/kg/day depending on age and pubertal status.
• Insulin types include rapid-acting (lispro, aspart, glulisine), short-acting (regular), intermediate-acting (NPH), and long-acting (glargine, detemir, degludec). Children on MDI typically receive long-acting insulin once or twice daily and rapid-acting insulin before meals based on carbohydrate counting and correction factors.

Blood Glucose Monitoring

• Regular blood glucose monitoring is essential for diabetes management in children, with recommended frequency of 6-10 times daily for those using multiple daily injections. Continuous glucose monitoring (CGM) systems provide real-time glucose readings and trend information, allowing for more proactive management and detection of hypoglycemia.
• Target blood glucose ranges for children with diabetes are typically 80-130 mg/dL before meals and <180 mg/dL post-meals, with HbA1c targets of <7.0% for most children, though goals should be individualized. Nighttime glucose targets are often set higher (100-150 mg/dL) to prevent nocturnal hypoglycemia.

Nutritional Management

• Nutritional management for children with diabetes focuses on carbohydrate counting, which allows for flexible meal planning and accurate insulin dosing. The insulin-to-carbohydrate ratio (I:C) typically ranges from 1:5 to 1:15 (1 unit of insulin for every 5-15g of carbohydrate) and is individualized based on age, weight, and insulin sensitivity.
• Recommended dietary composition includes 45-55% of calories from carbohydrates, 15-20% from protein, and 25-35% from fat (primarily unsaturated). Regular meal timing is important, especially for children on fixed insulin regimens, while those on intensive insulin therapy or pumps can have more flexible meal schedules.

Exercise Considerations

• Physical activity is beneficial for children with diabetes but requires careful management as exercise increases glucose uptake and insulin sensitivity. For planned exercise, insulin doses may need to be reduced by 20-50% depending on intensity and duration, and additional carbohydrates may be needed (typically 15-30g per hour of moderate activity).
• Blood glucose should be checked before, during (for prolonged activity), and after exercise. Exercise should be avoided if blood glucose is >250 mg/dL with ketones or <90 mg/dL. The risk of hypoglycemia is increased for up to 24 hours after significant exercise due to increased insulin sensitivity and glycogen replenishment.

Microvascular Complications

• Diabetic retinopathy is damage to the retinal blood vessels caused by chronic hyperglycemia. Screening should begin at age 11 with 2-5 years of diabetes duration or at puberty onset in those with diabetes for 3-5 years. Annual comprehensive eye examinations are recommended thereafter.
• Diabetic nephropathy involves kidney damage characterized by albuminuria and declining glomerular filtration rate. Screening should begin at age 10 with 5 years of diabetes duration via annual urine albumin-to-creatinine ratio testing. Early detection and treatment with ACE inhibitors can slow progression.
• Diabetic neuropathy affects peripheral and autonomic nerves. Screening should begin at age 10 with 5 years of diabetes duration through annual comprehensive foot examinations and assessment of symptoms like numbness, tingling, or pain.

Psychosocial Considerations

• Children with diabetes face unique psychosocial challenges including disease burden, fear of hypoglycemia, body image concerns, and peer relationships. Diabetes distress and depression are more common in youth with diabetes, with approximately 20% experiencing clinically significant depression compared to 7% of peers without diabetes.
• Adolescence presents particular challenges due to hormonal changes affecting insulin sensitivity, desire for independence, risk-taking behaviors, and competing priorities. Non-adherence to treatment regimens is common during this period, with studies showing that only 21% of adolescents meet all treatment goals.

Transition to Adult Care

• Transition planning should begin in early adolescence (12-14 years) with a structured process to prepare for transfer to adult care, typically between ages 18-21. The transition process should include gradual shifting of self-management responsibilities, development of self-advocacy skills, and education about adult healthcare systems.
• Key transition readiness skills include independent diabetes management, scheduling appointments, communicating with providers, refilling prescriptions, and understanding insurance. Studies show that structured transition programs reduce gaps in care and emergency department visits during the transition period.

Type 1 vs. Type 2 Diabetes in Children

DKA vs. Hyperosmolar Hyperglycemic State (HHS)

Hypoglycemia vs. Insulin Shock

• Though often used interchangeably, hypoglycemia refers to low blood glucose (<70 mg/dL) with mild to moderate symptoms, while insulin shock refers specifically to severe hypoglycemia with altered mental status, loss of consciousness, or seizures requiring assistance from others for treatment.
• The treatment for mild to moderate hypoglycemia follows the "15-15 rule" (15g fast-acting carbohydrate, recheck in 15 minutes), while insulin shock requires glucagon administration (0.5mg for children <25kg, 1mg for ≥25kg) via injection or nasal spray, followed by emergency medical attention.

Memorizing Signs of Hypoglycemia

Remembering DKA Assessment

Insulin Action Memory Aid

Common Pitfalls in NCLEX Questions

• When answering NCLEX questions about pediatric diabetes, avoid the common pitfall of applying adult diabetes concepts directly to children. Children have different insulin requirements (often higher per kg), more pronounced hormonal effects during growth and puberty, and unique developmental and psychosocial needs that affect management.
• Another common error is confusing the presentation of new-onset T1DM with other conditions. Remember that new-onset diabetes in children can mimic gastroenteritis (due to vomiting from DKA), appendicitis (due to abdominal pain from DKA), or urinary tract infection (due to polyuria and sometimes enuresis).