Management of Microscopic Hematuria in Children

Initial Evaluation

The American College of Radiology recommends confirming true microscopic hematuria by verifying ≥5 red blood cells per high-power field in 2-3 consecutive urine specimens, as dipstick positivity alone is insufficient 1, 2
Investigate factitious causes of "hematuria" such as food substances or medications that may color the urine without actual red blood cells 1
Assess for proteinuria, which if present (>2+ by dipstick) suggests glomerular disease and requires more extensive evaluation 1, 2
Evaluate for hypercalciuria with a spot urine calcium-to-creatinine ratio, as this is a common cause of microscopic hematuria in children 3
Obtain urine culture to rule out urinary tract infection, which would direct care differently 1

Obtain thorough history focusing on family history of stone disease, hearing loss, or familial renal disease 1
History of trauma, recent viral illness, or hypertension is also relevant 1, 4
Medication use that could affect urine color should be assessed 1
Physical examination should assess for height and weight to evaluate growth 1
Blood pressure should be screened to assess for hypertension 1, 4
Presence of edema, rashes, or arthritis that might suggest systemic disease should be evaluated 1

Basic laboratory screening should include urinalysis with microscopic examination to assess for dysmorphic RBCs or red cell casts (suggesting glomerular source) 1, 4
Serum creatinine and blood urea nitrogen should be assessed to evaluate kidney function 1
Complete blood count with platelets should be performed 1

For isolated microscopic hematuria without proteinuria, clinical follow-up is recommended without immediate imaging, as these patients are unlikely to have clinically significant renal disease 1, 3
Family screening may be useful to identify benign familial hematuria, including thin basement membrane nephropathy 3
For microscopic hematuria with proteinuria or other concerning features, more extensive evaluation is warranted, including renal ultrasound to assess kidney size and structure 1, 3

Thin basement membrane nephropathy is the most common cause of persistent microscopic hematuria 3
IgA nephropathy (Berger disease) is another possible cause 1
Idiopathic hypercalciuria is a common cause of microscopic hematuria in children 3
For persistent unexplained microscopic hematuria without proteinuria, periodic urinalysis to monitor for development of proteinuria and blood pressure monitoring are recommended 4
Consider renal ultrasound if hematuria persists to evaluate for occult anatomic abnormalities, though yield is low 3

Isolated microscopic hematuria in children has a much lower risk of significant urologic disease compared to adults, particularly those over 40 6, 7
The presence of dysmorphic red blood cells and red cell casts strongly suggests glomerular disease and warrants nephrology referral 4, 5
CT imaging is not appropriate in the initial evaluation of isolated microscopic hematuria without proteinuria in children 3
Most children with isolated microscopic hematuria have a benign course and do not require extensive workup 1