Management of Transient Microscopic Hematuria in Infants

Rationale for Conservative Management

The American College of Radiology recommends no imaging or further workup for a 3-month-old infant with transient microscopic hematuria who is otherwise well and happy, as patients without proteinuria or dysmorphic red blood cells are unlikely to have clinically significant renal disease 1
Transient microscopic hematuria in infants, defined as tiny red flecks of blood in 2 diapers that has already resolved, does not require further evaluation, according to the American College of Radiology 1
A large study of 325 pediatric patients with microscopic hematuria found no clinically significant findings on renal ultrasound or voiding cystourethrography, supporting a conservative management approach 1

If hematuria recurs or persists, urinalysis with microscopic examination should be obtained to document ≥5 red blood cells per high-powered field, as recommended by the American College of Radiology 1
The presence of proteinuria, dysmorphic red blood cells, or red cell casts in the urine should be checked, as these findings may indicate glomerular disease requiring nephrology referral, according to the American College of Radiology and other guidelines 1, 2

Imaging, such as renal and bladder ultrasound, is only indicated if hematuria becomes persistent, defined as present in 2 or 3 of 3 consecutive properly collected specimens, or if the infant develops macroscopic/gross hematuria, associated symptoms, or becomes symptomatic or unwell, as recommended by the American College of Radiology 1, 3

Advanced imaging modalities, such as CT, MRI, or VCUG, are not appropriate for isolated, transient microscopic hematuria in an otherwise well infant and expose the child to unnecessary risk, according to the American College of Radiology guidelines 1, 3
Isolated microscopic hematuria is very rarely the presenting scenario of Wilms tumor, and the brief, self-limited nature of this finding should not trigger oncologic concerns, as stated by the American College of Radiology 1

Parents should be reassured and provided with anticipatory guidance, including monitoring for recurrence of blood in diapers and returning if hematuria recurs, persists, or if the infant develops concerning symptoms, as recommended by the American College of Radiology 1
No follow-up testing is needed unless hematuria recurs, at which point screening for benign causes, such as recent vigorous activity, minor trauma, urinary tract infection, or recent illness, should be considered, according to guidelines 2