What is the appropriate workup for a patient presenting with hematuria (blood in urine)?

Hematuria Workup

All patients with gross hematuria should be referred for urgent urologic evaluation due to the high risk of underlying malignancy (>10%), even if self-limited. 1

Initial Assessment

Microscopic vs. Gross Hematuria

• Gross hematuria: Visible blood in urine
  • Higher association with malignancy (30-40%)
  • Requires complete urologic workup in all cases 2
• Microhematuria: ≥3 red blood cells per high power field on microscopic evaluation
  • Lower risk of malignancy (2.6-4%)
  • Workup depends on risk factors 2, 1

Risk Factors for Urologic Malignancy

• Age >60 years
• Male gender
• Smoking history
• Family history of renal cell carcinoma
• Occupational exposure to chemicals or dyes
• Gross hematuria
• History of pelvic irradiation
• Chronic urinary tract infection
• Chronic indwelling foreign body 2, 1

Diagnostic Algorithm

For Gross Hematuria:

1. Urinalysis and urine culture to confirm hematuria and rule out infection
2. CT urography (first-line imaging modality) including:
   • Unenhanced images
   • Contrast-enhanced nephrographic phase
   • Excretory phase 1
3. Cystoscopy to evaluate the bladder and urethra 1

For Microscopic Hematuria:

1. Initial evaluation:

   • Urinalysis to confirm hematuria
   • Urine culture to rule out infection
   • Serologic testing (creatinine, BUN)

2. Risk stratification:

   • High-risk patients (with risk factors): Follow same workup as gross hematuria
   • Low-risk patients (without risk factors):
     • If benign cause identified (exercise, menstruation, infection, trauma, recent urologic procedure): Treat cause and repeat urinalysis
     • If no benign cause: Proceed with imaging and cystoscopy 2, 1

Imaging Options

Imaging Modality	Indication	Sensitivity	Specificity
CT Urography	Primary imaging modality	92%	93%
MR Urography	Contrast allergy or renal insufficiency	High	High
Renal Ultrasound	Alternative or in young patients	50%	95%

• CT urography is the gold standard for upper tract evaluation 2, 1
• MR urography is an alternative for patients with contrast allergy or renal insufficiency 1
• Ultrasound may be appropriate for initial evaluation in patients ≤40 years with microscopic hematuria 3

Special Considerations

Age-Based Approach

• Patients ≤40 years old:

  • Lower risk of malignancy
  • Consider non-contrast CT or ultrasound for microscopic hematuria
  • Add cystoscopy if gross hematuria present 3

• Patients >40 years old:

  • Higher risk of malignancy
  • Complete evaluation with CT urography and cystoscopy 3

Pregnant Patients

• Ultrasound is the preferred initial imaging modality
• MRI without gadolinium if further imaging is needed 2

Anticoagulation

• Anticoagulant or antiplatelet therapy does not eliminate the need for complete hematuria evaluation 1

Follow-up Recommendations

• If initial evaluation is negative:

  • Repeat urinalysis at 6,12,24, and 36 months
  • Monitor blood pressure
  • Immediate re-evaluation if:
    • Recurrent gross hematuria
    • Abnormal urinary cytology
    • New irritative voiding symptoms 1

• Patients with persistent asymptomatic microhematuria:

  • Annual urinalysis
  • Consider repeat evaluation within 3-5 years for persistent or recurrent hematuria 1

Common Pitfalls

1. Incomplete evaluation: Failing to perform both imaging and cystoscopy can miss significant pathology
2. Ignoring gross hematuria: Even a single episode requires complete evaluation
3. Over-investigating low-risk patients: Patients with identified benign causes of microhematuria may not need complete workup
4. Inadequate follow-up: Patients with negative initial workup but persistent hematuria need continued surveillance
5. Relying solely on urine cytology: Low sensitivity (37%) makes it inadequate as a standalone test 3