Pediatrics · Year 3 · from Pediatrics

Case 1: Diabetic Ketoacidosis - New Onset Type 1 Diabetes

Patient Demographics

  • Age: 10-year-old female
  • Sex: Female

Chief Complaint

"She's been drinking a lot of water, urinating frequently, and now she's vomiting and seems confused."

History of Present Illness

A 10-year-old previously healthy female presents with 3 weeks of progressive polyuria, polydipsia, and a 4 kg weight loss despite increased appetite. Over the past 2 days, she has developed nausea, vomiting, and abdominal pain. Today, she became increasingly lethargic and her breathing has become deep and rapid. Her parents initially thought she had a stomach virus. There is no prior history of diabetes, but her maternal grandmother has type 2 diabetes. She has had no recent illnesses or medication use.

Physical Examination

  • General: Ill-appearing, lethargic but arousable, deep rapid breathing (Kussmaul respirations)
  • Vital signs: Temp 36.5°C, HR 130 bpm, RR 32/min (deep), BP 95/60 mmHg, Weight 28 kg (down from 32 kg 3 weeks ago)
  • HEENT: Dry mucous membranes, sunken eyes, fruity odor on breath
  • Cardiovascular: Tachycardic, regular rhythm, no murmur
  • Respiratory: Clear, deep breathing
  • Abdomen: Soft, diffusely tender, no guarding or rebound
  • Skin: Dry, poor turgor (tenting)
  • Neurologic: Lethargic, oriented to person only, moves all extremities

Workup

  • Point-of-care glucose: 485 mg/dL
  • BMP: Na 131 mEq/L (corrected Na 138), K 5.4 mEq/L, Cl 98 mEq/L, HCO3 8 mEq/L, BUN 28 mg/dL, Cr 1.1 mg/dL, Glucose 478 mg/dL
  • Anion gap: 25 (elevated)
  • VBG: pH 7.12, pCO2 18 mmHg
  • Serum ketones: Strongly positive (beta-hydroxybutyrate 6.8 mmol/L)
  • Urinalysis: Glucose 3+, ketones 3+
  • HbA1c: 12.8%

Diagnosis

Diabetic ketoacidosis (severe) as initial presentation of Type 1 diabetes mellitus

Clinical Reasoning

This child presents with classic new-onset type 1 diabetes complicated by severe DKA. The triad of polyuria, polydipsia, and weight loss reflects hyperglycemia and catabolism from insulin deficiency. DKA criteria are met: glucose >200 mg/dL, pH <7.3 (actually <7.15, indicating severe DKA), bicarbonate <15 mEq/L, and positive ketones. The elevated anion gap reflects unmeasured ketoacids. The HbA1c of 12.8% indicates the hyperglycemia has been present for weeks. The abdominal pain is common in DKA and typically resolves with treatment. Her altered mental status places her at higher risk for cerebral edema.

Management

  1. Initial fluid resuscitation: 10 mL/kg NS bolus over 1 hour (not faster due to cerebral edema risk)
  2. Maintenance fluids: Calculate deficit replacement over 24-48 hours; use 0.45% or 0.9% NS based on sodium trends
  3. Insulin infusion: Start regular insulin 0.05-0.1 units/kg/hour AFTER initial fluid bolus
  4. Potassium replacement: Add 40 mEq/L KCl to fluids once K <5.5 mEq/L and patient urinating
  5. Add dextrose: When glucose reaches 250-300 mg/dL, add D5 or D10 to fluids while continuing insulin until acidosis resolves
  6. Monitoring: Glucose hourly, BMP Q2-4h, neuro checks Q1h
  7. Cerebral edema precautions: Head of bed 30 degrees; have mannitol or 3% saline at bedside; watch for headache, altered mental status, bradycardia, hypertension
  8. Transition: When pH >7.3, bicarbonate >15, patient eating, transition to subcutaneous insulin with basal-bolus regimen
  9. Diabetes education: Initiate comprehensive education before discharge

Clinical Image

Image Description: Clinical presentation of diabetic ketoacidosis demonstrating the typical signs of dehydration and metabolic derangement seen in this serious diabetes complication.

Source: Wikimedia Commons URL: https://commons.wikimedia.org/wiki/File:Diabetic_ketoacidosis.jpg License: CC BY-SA 4.0

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