What is the appropriate evaluation and treatment approach for a pediatric patient presenting with hematuria?

Evaluation and Management of Pediatric Hematuria

Initial Clinical Assessment

Begin with a focused history targeting specific red flags: recent streptococcal infection, family history of renal disease or hearing loss (Alport syndrome), sickle cell disease, bleeding disorders, urolithiasis, recent trauma, strenuous exercise, dysuria, flank pain, and medications. 1, 2

Key historical elements include:

• Urinary tract infection symptoms (dysuria, frequency, urgency) 1
• Tropical exposure and bloody diarrhea (suggesting post-infectious causes) 1
• Joint pains and rash (Henoch-Schönlein purpura, systemic lupus erythematosus) 1
• Family history of stone disease, hearing loss, and hypertension 1
• Occult trauma or foreign body insertion (consider abuse) 1

Physical examination priorities:

• Measure height and weight as indicators of chronic disease 2
• Assess for fevers, arthritis, rashes, soft-tissue edema 1, 2
• Examine for nephromegaly, abdominal masses 1, 2
• Check for genital or anal bleeding suggesting sexual abuse 1, 2
• Evaluate for deafness and costovertebral angle tenderness 1, 2

Urinalysis: The Critical Differentiator

Perform thorough urinalysis with microscopic examination to differentiate glomerular from non-glomerular causes—this fundamentally determines your entire diagnostic pathway. 2

Glomerular Pattern (Medical Nephrology)

• Tea-colored urine with proteinuria (>2+ by dipstick) 1, 2
• Red blood cell casts (pathognomonic for glomerular disease) 1, 2
• Dysmorphic red blood cells (>80%) best seen with phase contrast microscopy 1, 2

Non-Glomerular Pattern (Urologic)

• Bright red or pink urine 3
• Normal-appearing red blood cells (>80%) 3
• Absence of proteinuria and casts 1

Additional urinalysis findings:

• White cells and microorganisms indicate urinary tract infection 1, 2
• Evaluate for hypercalciuria using spot urine calcium-to-creatinine ratio 1, 2

When chronic kidney disease is suspected:

• Obtain blood urea nitrogen, serum creatinine, and complete blood count with platelets 1, 2

Imaging Algorithm by Clinical Scenario

Isolated Microscopic Hematuria (Nonpainful, Nontraumatic)

For isolated microscopic hematuria without proteinuria or dysmorphic red blood cells in an otherwise well child, no imaging is indicated. 1, 2 This recommendation is based on a study of 325 pediatric patients where 87% underwent renal ultrasound and 24% had voiding cystourethrography, with no clinically significant findings discovered. 1

Critical pitfall: Advanced imaging modalities such as CT, MRI, or VCUG are not appropriate for isolated, transient microscopic hematuria and expose the child to unnecessary risk. 2

Management approach:

• Screen family members' urine for benign familial hematuria or thin basement membrane nephropathy 1
• Long-term follow-up is mandatory as microscopic hematuria can rarely be the first sign of occult renal disease 4

Isolated Macroscopic (Gross) Hematuria (Nonpainful, Nontraumatic)

Ultrasound of the kidneys and bladder is the initial imaging modality of choice for isolated macroscopic hematuria, as it effectively displays kidney anatomy and screens for structural lesions. 2 Ultrasound is highly sensitive, readily available, requires no ionizing radiation, and can be performed without anesthesia or contrast. 5

Plain radiography may be performed concurrently to detect calcifications and radiopaque stones. 2

A thorough diagnostic evaluation is warranted for gross hematuria because clinically important structural abnormalities of the urinary tract are commonly discovered in children with asymptomatic gross hematuria. 4

Painful Hematuria (Suspected Urolithiasis)

Ultrasound of the kidneys and bladder is the first-line imaging for painful hematuria suspected to be due to urolithiasis. 2 However, ultrasound has limited sensitivity for ureteral stones. 2

CT may be particularly useful when kidney and bladder ultrasound is negative but clinical suspicion for urolithiasis remains high, especially if detection would impact treatment. 2 CT has sensitivity and specificity both well above 90% for stone detection in adults, with proper low-dose techniques reducing radiation to less than traditional intravenous urography. 2

Hematuria with Palpable Abdominal Mass

This scenario fundamentally changes the clinical approach—urgent ultrasound evaluation is required, as it raises concern for Wilms tumor or other renal masses. 2, 5

Ultrasound is critical for:

• Confirming renal origin of the mass 2, 5
• Assessing the contralateral kidney 2, 5
• Evaluating for inferior vena cava involvement 2, 5
• Determining tumor size and extent 2

After ultrasound confirms a renal mass, proceed urgently to chest CT for staging and consider contrast-enhanced abdominal CT or MRI to define local extent and vascular invasion. 2

Critical pitfall: Delaying imaging by assuming isolated hematuria requires no workup when an abdominal mass is present can lead to delayed diagnosis and treatment. 2 Isolated microscopic hematuria is very rarely the presenting scenario of Wilms tumor; brief, self-limited findings should not trigger oncologic concerns. 2

Traumatic Hematuria

Macroscopic hematuria following trauma necessitates radiologic evaluation with contrast-enhanced CT of the abdomen and pelvis. 2 All CT scans must be performed with intravenous contrast unless specifically contraindicated. 2

Isolated microscopic hematuria without clinical or laboratory findings of visceral trauma or concerning mechanism does not need emergency investigation. 2

Radiologic evaluation for renal injury is indicated when:

• ≥50 red blood cells are present on urinalysis 2
• The patient is hypotensive on presentation (though hypotension is an unreliable clinical indicator in children) 2
• Based on mechanism of injury 2

Blood in the urethral meatus with pelvic fractures should prompt investigation of the urethra and bladder, as there is a 50% incidence of genitourinary injury. 2

Minor trauma to an anomalous kidney can cause major clinical repercussions, as renal anomalies occur in 1-4% of the population. 2

When to Refer to Nephrology

Consider nephrology referral when glomerular hematuria is suspected based on:

• Persistent significant proteinuria (protein-to-creatinine ratio >0.2 for three specimens) 3
• Presence of red blood cell casts or >80% dysmorphic RBCs 3
• Elevated creatinine or declining renal function 3
• Hypertension with hematuria and proteinuria 3

Advanced medical assessment for glomerulonephritis and vasculitis should be performed if suggested by initial workup, including:

• Audiogram and slit lamp examinations if there is suspicion for Alport syndrome 1
• Complement levels (C3, C4) to evaluate for post-infectious glomerulonephritis or lupus nephritis 3
• Antinuclear antibody (ANA) and ANCA testing if vasculitis suspected 3

When to Refer to Urology

Indications for urologic referral are more limited in pediatrics and include:

• Stones that do not pass spontaneously or are more than 5 mm in diameter 6
• Renal injury from trauma 6
• Anatomic abnormalities 6
• Gross hematuria that seems to originate from the urinary tract and is without an identified cause 6

Common Causes by Presentation

Microscopic Hematuria

The most common cause discovered in children with microscopic hematuria is hypercalciuria (16%), followed by post-streptococcal glomerulonephritis (1%). 4 In 80% of cases, no cause is uncovered. 4

Gross Hematuria

The most common cause discovered in children with gross hematuria is hypercalciuria (22%). 4 In approximately 38% of cases, no cause is uncovered. 4 Among those qualifying for renal biopsy, IgA nephropathy is the most common diagnosis. 4

Special Diagnostic Considerations

Thin basement membrane nephropathy and IgA nephropathy (Berger disease) are separable only by renal biopsy results—thin basement membrane nephropathy is benign while IgA nephropathy may be progressive, mandating referral to a nephrologist. 7 The prognosis of thin basement membrane nephropathy is excellent. 7

Definite medical diagnosis can sometimes be suggested by clinical evaluation alone for conditions such as post-infectious glomerulonephritis, Henoch-Schönlein purpura, coagulopathy, sickle cell disease, systemic lupus erythematosus, or infection. 1

Many patients with isolated microscopic hematuria who are otherwise asymptomatic are followed clinically without more extensive workup. 1