Workup for Hematuria
The workup for hematuria should follow a risk-stratified approach, with all patients requiring microscopic confirmation of ≥3 RBCs/HPF in properly collected specimens, followed by risk assessment and appropriate imaging and cystoscopy based on risk level. 1
Diagnosis Confirmation
- Confirm hematuria with microscopic urinalysis showing ≥3 RBCs/HPF in 2 of 3 properly collected specimens 1
- Dipstick positivity alone is insufficient and requires microscopic confirmation 2
- Assess for dysmorphic RBCs, RBC casts, and significant proteinuria (>500-1000mg/24hr) to differentiate glomerular from non-glomerular sources 1
Risk Stratification
Risk stratification is essential for determining the appropriate evaluation pathway:
| Risk Level | Criteria |
|---|---|
| Low/Negligible (0-0.4%) | 3-10 RBC/HPF + Age <60y (women) or <40y (men) + Never smoker or <10 pack-years |
| Intermediate (0.2-3.1%) | 11-25 RBC/HPF or Age 60+ (women)/40-59 (men) or 10-30 pack-years smoking |
| High (1.3-6.3%) | >25 RBC/HPF or Age 60+ (men) or >30 pack-years smoking or gross hematuria |
Initial Laboratory Evaluation
- Complete urinalysis with microscopy
- Serum creatinine and BUN to assess renal function
- Complete blood count
- Urine culture to rule out infection
- 24-hour urine collection for protein quantification if glomerular source suspected 1
Imaging and Procedural Evaluation
For Gross Hematuria (Regardless of Risk Level)
- Cystoscopy is mandatory (sensitivity 87-100% for bladder cancer) 1
- CT urography (multiphasic) as the imaging procedure of choice 2, 1
For Microscopic Hematuria
- Low-risk: Renal ultrasound 1
- Intermediate-risk: Cystoscopy and renal ultrasound 1
- High-risk: Cystoscopy and CT urography 2, 1
Alternative Imaging Options (If CT Urography Contraindicated)
- MR urography for patients with contrast allergy or renal insufficiency
- Retrograde pyelograms in combination with non-contrast CT, MRI, or ultrasound 2, 1
Special Considerations
- Age considerations: All patients ≥35 years should undergo cystoscopy 2
- Anticoagulation: Patients on antiplatelet agents or anticoagulants require the same evaluation as those not on these medications 1
- Pregnancy: Ultrasound is the preferred initial imaging modality 2
- Children: Different evaluation approach focusing on stone disease, hearing loss, familial renal disease, and hypertension 1
Common Pitfalls to Avoid
- Attributing hematuria to anticoagulation without further evaluation - Anticoagulation rarely causes hematuria without underlying pathology 1
- Failing to confirm dipstick positivity with microscopy - False positives are common with dipstick testing 2
- Neglecting to evaluate leukocyturia without bacteriuria - May miss non-infectious causes 1
- Using urinary cytology or urine-based molecular markers for initial bladder cancer detection - Not recommended for initial screening 1
- Inadequate follow-up - Patients with persistent hematuria require continued surveillance 1
Follow-Up Recommendations
- Repeat urinalysis after treatment of identified causes
- For persistent microscopic hematuria of unknown cause, follow-up urinalysis at 6,12,24, and 36 months 1
- Immediate re-evaluation if recurrent gross hematuria, abnormal urinary cytology, or new irritative voiding symptoms occur 1
- Consider nephrology referral for possible renal biopsy if glomerular source suspected 1
The workup for hematuria must be thorough and systematic, as the risk of malignancy with gross hematuria exceeds 10%, while microscopic hematuria may indicate serious underlying conditions requiring prompt evaluation 3.