What is the appropriate evaluation and management of hematuria?

Evaluation and Management of Hematuria

All patients with gross hematuria require urgent urologic referral due to a >10% risk of urologic cancer, while microscopic hematuria requires risk-stratified evaluation based on patient factors and presentation characteristics. 1, 2

Classification and Initial Assessment

Types of Hematuria

• Gross hematuria: Visible blood in urine
  • Painless gross hematuria has stronger association with cancer
  • Gross hematuria with flank pain suggests urinary stone disease 2
• Microscopic hematuria: ≥3 red blood cells per high-power field
  • Prevalence: 0.9-18% in adults 2
  • Cancer risk: 0.5-5% overall, but 7-20% in high-risk subgroups 2

Key Clinical Features to Assess

• Urine characteristics: Tea-colored (glomerular) vs. bright red with clots (lower tract) 1
• Associated symptoms: Flank pain, fever, weight loss, night sweats, fatigue, hypertension 1
• Medical history: Renal stones, polycystic kidney disease, sickle cell disease, bleeding disorders, recurrent UTIs 1
• Risk factors for malignancy:
  • Age >60 years
  • Smoking history
  • Male gender
  • Occupational exposure to chemicals/dyes
  • Previous urologic disorders 1

Diagnostic Evaluation

Initial Laboratory Testing

1. Urinalysis with microscopic examination:

   • Confirms hematuria
   • Assesses RBC morphology (dysmorphic RBCs suggest glomerular source)
   • Evaluates for casts, crystals, pyuria, proteinuria 1

2. Basic laboratory tests:

   • Complete metabolic panel (serum creatinine, BUN)
   • Urine culture
   • Urine cytology 1

Imaging and Further Evaluation

Based on risk stratification:

High-Risk Patients (Any of the following)

• Gross hematuria
• Age >60 years
• Smoking history
• Occupational exposures
• Male gender

Recommended evaluation:

1. CT urography (92% sensitivity, 93% specificity for urinary tract pathology) 1
2. Urethrocystoscopy
3. Urine cytology 1

Lower-Risk Patients

• Younger patients
• No risk factors

Recommended evaluation:

1. Renal ultrasound (less radiation, but only 50% sensitivity) 1
2. Consider urethrocystoscopy based on clinical suspicion 1

Special Considerations

• Renal insufficiency or contrast allergy: Use MR urography or ultrasound instead of CT 1
• Glomerular source suspected (dysmorphic RBCs, proteinuria, RBC casts): Consider nephrology referral 1

Management Approach

Referral Guidelines

• Mandatory urology referral for:

  • All cases of gross hematuria
  • Microscopic hematuria with risk factors 1

• Consider nephrology referral if:

  • eGFR <60 ml/min/1.73m²
  • Significant proteinuria
  • Dysmorphic RBCs or red cell casts 1

Treatment of Underlying Conditions

• Urologic conditions: Directed by urologist based on findings
• Glomerular disease:
  • Blood pressure control (target <130/80 mmHg)
  • ACE inhibitors or ARBs as first-line agents 1

Follow-up

• Patients with persistent hematuria require continued surveillance
• Repeat urinalysis within 12 months
• New symptoms, gross hematuria, or increased degree of microscopic hematuria should prompt immediate re-evaluation 1

Common Pitfalls and Caveats

1. Don't screen asymptomatic patients for hematuria - not recommended by any major health organization 2

2. Don't dismiss self-limited gross hematuria - even resolved episodes warrant evaluation due to high cancer risk (OR 7.2) 1

3. Don't assume microscopic hematuria is benign - while most common causes are benign (UTI, BPH, urinary calculi), cancer risk remains significant in high-risk groups 3

4. Don't miss glomerular causes - dysmorphic RBCs, proteinuria, and RBC casts suggest kidney disease requiring nephrology input 1

5. Recognize that "idiopathic microscopic hematuria" accounts for approximately 80% of cases after complete evaluation 4