From the Guidelines
The proper workup of isolated microhematuria in men should begin with a thorough history and physical examination, followed by specific diagnostic tests, including a repeat urinalysis, urine culture, comprehensive metabolic panel, renal function tests, and imaging studies with a CT urogram, as well as cystoscopy for men over 35 years old or those with risk factors, as recommended by the most recent guidelines 1.
Initial Evaluation
The initial evaluation of microhematuria should include:
- A thorough history and physical examination to identify potential causes of microhematuria
- A repeat urinalysis to confirm persistence of microhematuria
- Urine culture to rule out infection
- Comprehensive metabolic panel and renal function tests to assess for underlying kidney disease
Imaging Studies
Imaging studies are essential in the evaluation of microhematuria, with a CT urogram being the preferred modality, as it can detect urinary tract stones, renal masses, and urothelial lesions 1.
Cystoscopy
For men over 35 years old or those with risk factors such as smoking history, cystoscopy is recommended to directly visualize the bladder and urethra for potential tumors or other abnormalities, with a sensitivity ranging from 87% to 100% and specificity ranging from 64% to 100% 1.
Additional Tests
Additional tests may include:
- Urine cytology to detect malignant cells
- Measurement of urine protein and creatinine ratio to assess for glomerular disease
Follow-up
If all tests are negative, follow-up urinalysis should be performed at 6,12, and 24 months, with consideration for nephrology referral if proteinuria or declining renal function is present, as the incidence of malignancies after an initial negative work-up is low, but not negligible 1.
From the Research
Diagnostic Evaluation of Isolated Microscopic Hematuria in Males
- The diagnostic evaluation of isolated microscopic hematuria (microhematuria) in males involves a thorough history and physical examination, measurement of inflammatory parameters and renal function tests, and ultrasonography of the kidneys and bladder 2.
- Patients with non-glomerular asymptomatic microhematuria (aMH) who have risk factors such as smoking, advanced age, and male sex are more likely to have relevant underlying conditions and should therefore undergo augmented, risk-adapted diagnostic evaluation with urethrocystoscopy, urine cytology, and, when indicated, CT urography 2.
- The basic diagnostic evaluation for microhematuria includes laboratory tests to rule out intrinsic renal disease, imaging of the urinary tract, and referral to nephrology and urology subspecialists 3.
Role of Cytologic Analysis and Follow-up
- Cytologic analysis of voided urine has been found to have limited sensitivity, cost-effectiveness, and ease of administration, and is not recommended as a replacement for more invasive diagnostics in the evaluation of microscopic hematuria 4.
- Patients with a negative work-up for asymptomatic microhematuria have a low chance of subsequently developing bladder cancer, and the recommended follow-up for these patients may require reconsideration 5.
- Repeat urinary cytologies, urinalyses, and office visits for several years may not be necessary for patients with a negative evaluation, as the risk of developing bladder cancer is low 5.
Risk Factors and Underlying Conditions
- Risk factors such as smoking, advanced age, and male sex increase the likelihood of relevant underlying conditions in patients with non-glomerular aMH 2.
- Patients with isolated glomerular hematuria are at elevated risk for renal disease and should undergo follow-up checks at six-month intervals 2.
- Newly-discovered proteinuria on follow-up should be clarified by a nephrologist, as proteinuria could be a sign of significant glomerular disease 6.