What is the first step in evaluating a child presenting with enuresis, polydipsia, polyuria, and weight loss?

Immediate First Step: Urine Dipstick Test

The first step in evaluating this child is to perform a urine dipstick test (urinalysis) to immediately screen for glycosuria, which would indicate diabetes mellitus requiring urgent blood glucose testing. 1, 2

Clinical Reasoning

This presentation is highly concerning for new-onset diabetes mellitus rather than simple enuresis. The combination of enuresis with polydipsia, polyuria, and weight loss represents the classic triad of diabetes symptoms. 1 However, the International Children's Continence Society and American Academy of Child and Adolescent Psychiatry both emphasize that urine dipstick is the sole obligatory initial test when evaluating any child presenting with enuresis. 1, 2

The Algorithmic Approach

Step 1: Urine Dipstick (Answer B - but only the urinalysis component)

• Glycosuria on dipstick mandates immediate diabetes mellitus exclusion with blood glucose testing. 1, 2
• This takes minutes to perform and immediately identifies children requiring urgent intervention. 2
• Proteinuria would prompt kidney disease investigation. 1, 2

Step 2: If Glycosuria is Present → Random Blood Glucose

• Children presenting with polyuria, polydipsia, and weight loss who have glycosuria require immediate diagnostic blood glucose testing. 1
• Random plasma glucose ≥200 mg/dL with symptoms confirms diabetes mellitus. 1
• Youth with marked hyperglycemia (≥250 mg/dL) and symptoms should be treated with insulin immediately. 1

Step 3: If Glycosuria is Absent

• Consider other causes of polyuria-polydipsia syndrome (diabetes insipidus, kidney disease, psychogenic polydipsia). 3, 4, 5
• Proceed with enuresis-specific evaluation including frequency-volume chart. 1, 2

Critical Distinction

This is NOT simple monosymptomatic enuresis. The presence of polydipsia, polyuria, and weight loss are alarming symptoms that distinguish this from typical bedwetting. 1 Simple enuresis does not cause weight loss or excessive daytime thirst/urination. 2

Common Pitfalls to Avoid

• Never skip urinalysis - it is the only mandatory screening test and missing glycosuria could delay life-threatening diabetic ketoacidosis diagnosis. 1, 2
• Do not order random blood glucose first without urinalysis, as this violates standard enuresis evaluation protocols and may miss other urinary pathology. 1
• Do not assume this is behavioral enuresis - weight loss with polyuria/polydipsia demands metabolic investigation. 1
• Urine culture is not indicated as a first-line test unless urinalysis suggests infection (positive leukocyte esterase/nitrite). 1

Answer to the Question

Start with urinalysis (urine dipstick). If glycosuria is present, immediately proceed to blood glucose testing. The correct initial answer is B (Urine Analysis), which will then direct you to A (Random Blood Glucose) if diabetes is suspected. 1, 2

However, given the high clinical suspicion for diabetes mellitus in this presentation, both tests should be obtained urgently - but the urinalysis must be done first per standard enuresis evaluation guidelines. 1, 2