From the Guidelines
Hematuria, or blood in the urine, requires immediate evaluation to identify its cause and appropriate management, with a focus on ruling out underlying conditions such as urinary tract cancer, kidney stones, or infections. The evaluation and management of hematuria should prioritize morbidity, mortality, and quality of life as outcomes. Initial assessment should include a thorough history, physical examination, urinalysis, and urine culture. For microscopic hematuria (visible only under microscope), three or more red blood cells per high-power field on two of three properly collected urinalysis specimens is diagnostic 1.
Key Considerations
- Risk factors that require more urgent assessment include age over 35, smoking history, chemical exposure, prior urologic disease, and recent urinary tract infection.
- The workup typically includes complete blood count, renal function tests, and imaging studies such as CT urography or renal ultrasound.
- Cystoscopy is recommended for adults with persistent hematuria after initial evaluation, particularly those with risk factors for bladder cancer 1.
- Management depends on the underlying cause:
- Urinary tract infections require appropriate antibiotics (such as nitrofurantoin 100mg twice daily for 5-7 days for uncomplicated cases) 1.
- Kidney stones may need pain management with NSAIDs or narcotics, hydration, and possibly urologic intervention.
- Malignancies require referral to specialists.
- Benign causes like exercise-induced hematuria typically resolve with rest.
- Patients should be advised to increase fluid intake to maintain clear urine and follow up appropriately based on the identified cause.
Recent Guidelines
The American College of Physicians recommends that clinicians should include gross hematuria in their routine review of systems and specifically ask all patients with microscopic hematuria about any history of gross hematuria 1. Clinicians should not use screening urinalysis for cancer detection in asymptomatic adults 1. The most recent guidelines from 2020 suggest that all patients diagnosed with hematuria should undergo a thorough history and physical examination, urinalysis, and serologic testing prior to any initial imaging 1.
Ongoing Care
Persistent hematuria without an identified cause requires periodic reassessment, typically at 6-12 month intervals, to monitor for developing conditions. Clinicians should pursue evaluation of hematuria even if the patient is receiving antiplatelet or anticoagulant therapy 1. By following these guidelines and considering the individual patient's risk factors and presentation, clinicians can provide high-value care for patients with hematuria.
From the Research
Evaluation of Hematuria
- Hematuria can be evaluated using a comprehensive contrast material-enhanced multi-detector row computed tomography (CT) protocol that combines unenhanced, nephrographic-phase, and excretory-phase imaging 2
- The evaluation of hematuria includes laboratory tests to rule out intrinsic renal disease, imaging of the urinary tract, and referral to nephrology and urology subspecialists 3
- Imaging techniques such as intravenous urography, ultrasonography, CT, retrograde ureterography and pyelography, cystoscopy, and ureteroscopy can be used to evaluate patients with hematuria 2
Management of Hematuria
- Patients with gross hematuria have a higher risk of malignancy (>10%) and should be referred to a urologist promptly 3
- Microscopic hematuria most commonly has benign causes, such as urinary tract infection, benign prostatic hyperplasia, and urinary calculi 3
- Referral rates to urology for patients with microscopic hematuria are low, with only 36% of primary care physicians reporting referral 4
- Patients with hematuria and interstitial cystitis are unlikely to have a life-threatening urologic condition, with only 14% of patients having positive urologic findings 5
Practice Patterns
- Primary care physicians' practice patterns in evaluating hematuria vary, with some using urinalysis as a screening tool and others referring patients to urology 6, 4
- The use of cystoscopy, cytology, and upper tract imaging is limited in the evaluation of hematuria 6
- Further studies are needed to determine the extent of the problem and impact on morbidity and survival 6