What is the management for a 3-year-old patient with an infection on Intravenous Fluid (IVF) therapy who has glycosuria (2+ sugar in urine)?

Management of Glycosuria in a 3-Year-Old on Dextrose-Containing IV Fluids

Immediately check a blood glucose level and switch from DNS (Dextrose Normal Saline) to isotonic balanced solution without glucose or with reduced glucose concentration, as the glycosuria is most likely iatrogenic from excessive glucose administration rather than true diabetes. 1

Immediate Assessment

• Obtain a stat blood glucose measurement using a blood gas analyzer with glucose module if available, as this provides the most accurate results in young children 1
• Check for signs of hyperglycemia: polyuria beyond expected for IV fluid rate, polydipsia if child is alert, altered mental status 1
• Review the current IV fluid rate and total glucose delivery: DNS typically contains 5% dextrose, delivering substantial glucose load that can cause hyperglycemia and subsequent glycosuria 2

Fluid Management Algorithm

If blood glucose is >10 mmol/L (180 mg/dL):

• Stop DNS immediately and switch to isotonic balanced solution (Plain Lactated Ringer's) without glucose 1
• Consider low-dose continuous insulin infusion if blood glucose remains >10 mmol/L (180 mg/dL) on repeat testing 1
• Monitor blood glucose every 1-2 hours until stable 1

If blood glucose is 8-10 mmol/L (145-180 mg/dL):

• Reduce glucose concentration in IV fluid or switch to isotonic balanced solution with lower glucose content (1-2.5% dextrose) 1
• Recheck blood glucose in 2-4 hours 1

If blood glucose is <8 mmol/L (145 mg/dL):

• The glycosuria likely represents renal glycosuria from the infection/stress state or transient hyperglycemia 2
• Switch to isotonic balanced solution with appropriate glucose (sufficient to prevent hypoglycemia, typically 4-5% dextrose) 1
• Monitor blood glucose at least daily 1

Ongoing IV Fluid Prescription

• Use isotonic balanced solution (Plain Lactated Ringer's) as the base fluid to reduce hyponatremia risk and slightly reduce length of stay 1, 3
• Add glucose in sufficient amounts to prevent hypoglycemia (blood glucose monitoring at least daily to guide dosing) 1, 3
• Add potassium based on clinical status and regular monitoring to avoid hypokalemia 1, 3
• Calculate maintenance volume using Holliday-Segar formula but restrict to 65-80% of calculated volume to avoid fluid overload and prevent hyponatremia in this acutely ill child with infection 1, 3

Monitoring Parameters

• Blood glucose monitoring at least daily (more frequently if hyperglycemia persists) 1
• Daily electrolytes including sodium and potassium 1, 3
• Urine output and daily weights to assess fluid balance 3
• Repeat urinalysis after correcting hyperglycemia to confirm resolution of glycosuria 4

Critical Pitfall to Avoid

Do not assume this child has diabetes mellitus. In a 3-year-old on IV dextrose with infection, glycosuria with 2+ sugar is almost certainly iatrogenic hyperglycemia from excessive glucose administration (DNS at maintenance rates delivers 5-7 mg/kg/min glucose, which exceeds physiologic production) 2. The stress response to infection further impairs glucose tolerance 4. True diabetes presenting with infection would show marked hyperglycemia (>200 mg/dL), ketones, and metabolic acidosis—none of which are mentioned here 1.

Special Consideration for Infection

• Acute illness and infection increase endogenous ADH secretion, making this child particularly susceptible to hyponatremia if receiving excessive hypotonic fluids 1
• The infection itself can cause transient glucose intolerance and glycosuria even with normal blood glucose levels 4
• Hyperglycemia >8 mmol/L (145 mg/dL) should be avoided as it increases morbidity and mortality in acutely ill children 1