What is the management for microhematuria (presence of blood in urine) with no symptoms and a normal Prostate-Specific Antigen (PSA) level?

Management of Asymptomatic Microhematuria with Normal PSA

Patients with asymptomatic microhematuria should undergo a complete urologic evaluation including upper tract imaging and cystoscopy, even with normal PSA, as microhematuria may indicate underlying urologic malignancy. 1

Risk Stratification

The American Urological Association (AUA) defines three risk categories for patients with hematuria:

• Low risk (0-0.4% malignancy risk)
• Intermediate risk (0.2-3.1% malignancy risk)
• High risk (1.3-6.3% malignancy risk) 1

Risk factors that increase concern for urologic malignancy include:

• Age >60 years
• Male gender
• Smoking history
• Exposure to industrial chemicals
• Family history of renal cancer
• History of pelvic radiation 1

Initial Evaluation

1. Confirm microhematuria with microscopic examination

   • Microhematuria is defined as ≥3 red blood cells per high-power field on microscopic evaluation
   • Dipstick positivity should always be confirmed with microscopic examination (dipstick specificity only 65-99%) 1
   • Collect two to three properly collected urinalysis specimens to confirm persistence 1

2. Laboratory workup

   • Complete blood count
   • Serum creatinine and BUN
   • Urinalysis with microscopic examination
   • Urine culture to rule out infection 1

Diagnostic Imaging

CT Urography is the preferred imaging modality:

• Sensitivity of 92% and specificity of 93% for detecting urologic abnormalities
• Should include contrast enhancement unless contraindicated 1

Alternative imaging options:

• MR Urography: For patients with contrast allergy or renal insufficiency
• Renal Ultrasound: Alternative or in younger patients (sensitivity only 50%, specificity 95%) 1

Procedural Evaluation

Cystoscopy is essential to evaluate the lower urinary tract, even with normal PSA levels 1, 2

Management Algorithm

1. For patients <40 years with microhematuria and no risk factors:

   • Renal ultrasound or non-contrast CT
   • Consider cystoscopy if persistent 1, 3

2. For patients >40 years or with risk factors:

   • CT urography (pre- and post-contrast)
   • Cystoscopy 1, 3

3. Follow-up recommendations:

   • Low-risk patients: Annual urinalysis
   • Intermediate/high-risk patients: Urine cytology and repeat urinalysis at 6,12,24, and 36 months 1

Common Pitfalls to Avoid

1. Inadequate evaluation: Research shows 42.1% of patients with microhematuria receive no further evaluation, and only 12.8% are referred for urologic evaluation 4. This can lead to missed malignancies.

2. Attributing microhematuria to anticoagulation therapy: Anticoagulation may exacerbate bleeding but rarely causes it without underlying pathology 1.

3. Relying solely on dipstick testing: Always confirm with microscopic examination 1.

4. Assuming normal PSA rules out urologic issues: PSA is specific to prostate conditions and does not rule out bladder cancer, kidney cancer, or other urologic pathologies 1, 2.

5. Incomplete evaluation: Evaluating only the upper or lower urinary tract instead of both 1.

The evaluation of asymptomatic microhematuria should be thorough and systematic, as 2.6-4% of all patients with microhematuria may have malignant tumors of the kidneys or urinary tract, and this increases to up to 25.8% in high-risk populations 5.