How should microscopic hematuria be evaluated in a 69-year-old patient with 8 Red Blood Cells (RBC) per High Power Field (HPF) in a urine sample?

Evaluation of Microscopic Hematuria in a 69-Year-Old Patient

A 69-year-old patient with 8 RBC/HPF in a urine sample should undergo a complete urologic evaluation including cystoscopy and upper tract imaging due to high risk for urinary tract malignancy. 1, 2

Risk Assessment

The patient presents with several significant risk factors:

• Age ≥ 69 years (high-risk factor)
• Microscopic hematuria (8 RBC/HPF exceeds the diagnostic threshold of >3 RBC/HPF)

Diagnostic Criteria

• Microscopic hematuria is defined as >3 RBC/HPF on microscopic evaluation of a single, properly collected urine specimen 1
• The finding of 8 RBC/HPF clearly meets this diagnostic threshold

Recommended Evaluation Algorithm

Step 1: Initial Assessment

• Complete history focusing on risk factors for genitourinary malignancy:

  • Smoking history (especially >30 pack-years)
  • Occupational exposures to chemicals or dyes
  • History of pelvic radiation
  • Chronic urinary tract infections
  • Family history of urologic malignancy 2

• Physical examination including:

  • Blood pressure measurement
  • Genitourinary examination 1

Step 2: Laboratory Testing

• Serum creatinine and BUN to assess renal function
• Urinalysis with microscopic examination to confirm hematuria and assess for:
  • Dysmorphic RBCs (suggesting glomerular disease)
  • Proteinuria (suggesting renal disease)
  • Other cellular casts (suggesting renal disease) 2
• Urine culture to rule out infection as a benign cause 1

Step 3: Imaging Studies

• CT urography is the preferred imaging study for this high-risk patient 1, 2
• If CT is contraindicated (renal insufficiency or contrast allergy), alternatives include:
  • MR urography
  • Renal and bladder ultrasound 2

Step 4: Urologic Evaluation

• Cystoscopy is indicated in this high-risk patient 1
• Consider urine cytology as an adjunct test, though it has limited sensitivity (37%) 3

Important Considerations

Risk Stratification

This patient falls into the high-risk category based on:

• Age ≥69 years (men ≥40 years is considered high-risk) 2
• Degree of hematuria (8 RBC/HPF)

Anticoagulation Status

• If the patient is on anticoagulants or antiplatelet agents, the same evaluation should be performed as patients not on these agents 1
• Anticoagulation does not explain away microscopic hematuria and should not delay evaluation

Follow-up Recommendations

• If initial evaluation is negative but microscopic hematuria persists:
  • Annual urinalysis for surveillance
  • If two consecutive negative annual urinalyses, no further evaluation is necessary
  • For persistent or recurrent hematuria after initial negative workup, consider repeat evaluation within 3-5 years 2

Common Pitfalls to Avoid

1. Dismissing hematuria in older patients: The risk of malignancy increases with age, making thorough evaluation crucial in this 69-year-old patient.

2. Relying solely on dipstick testing: Dipstick testing alone is insufficient and can be confounded by various factors; microscopic confirmation is essential 1.

3. Inadequate imaging: Using only ultrasound in high-risk patients may miss significant pathology, as ultrasound has lower sensitivity (50%) compared to CT urography (92%) 3.

4. Delayed evaluation: Delays in evaluating hematuria can be associated with decreased survival in cases of malignancy 2.

5. Assuming benign etiology without complete workup: While benign causes are common, the 10% risk of malignancy in patients with hematuria warrants thorough evaluation 4.