What is the initial workup for microscopic hematuria in an adult male?

Initial Workup for Microscopic Hematuria in an Adult Male

For an adult male with microscopic hematuria, confirm the diagnosis with microscopic urinalysis showing ≥3 RBCs per high-power field on at least 2 of 3 properly collected clean-catch midstream specimens, then proceed with risk stratification to determine the extent of urologic evaluation required. 1

Step 1: Confirm True Hematuria

• Do not rely on dipstick testing alone, as it has limited specificity (65-99%) and can produce false positives from myoglobin, hemoglobin, or other substances 1, 2
• Obtain microscopic urinalysis on at least 2 of 3 properly collected clean-catch midstream urine specimens to document ≥3 RBCs/HPF before initiating any further workup 1
• Exclude transient benign causes before proceeding: recent vigorous exercise, sexual activity, viral illness, trauma, or recent urinary tract infection 1, 2

Step 2: Rule Out Infection

• If urinary tract infection is suspected based on symptoms or urinalysis findings, obtain urine culture before starting antibiotics 1, 2
• Treat the infection appropriately and repeat urinalysis 6 weeks after treatment completion to confirm resolution 1
• If hematuria persists after treating infection, proceed with full urologic evaluation—do not assume infection explains the hematuria 1

Step 3: Initial Laboratory Evaluation

Obtain the following tests to distinguish glomerular from non-glomerular sources and assess renal function:

• Complete urinalysis with microscopic examination of sediment for dysmorphic RBCs, red cell casts, white blood cells, and degree of proteinuria 1, 2
• Serum creatinine to assess renal function 1, 2
• Spot urine protein-to-creatinine ratio if dipstick shows proteinuria 1

Indicators of Glomerular Disease (Requires Nephrology Referral)

• Dysmorphic RBCs >80% 1, 2
• Red cell casts (pathognomonic for glomerular disease) 1, 2
• Significant proteinuria (protein-to-creatinine ratio >0.5 g/g or >500 mg/24 hours) 1, 2
• Elevated serum creatinine or declining renal function 1, 2
• Tea-colored or cola-colored urine 2

If glomerular features are present, refer to nephrology in addition to completing urologic evaluation, as malignancy can coexist with medical renal disease 2

Step 4: Risk Stratification for Urologic Malignancy

The American Urological Association stratifies patients based on age, smoking history, degree of hematuria, and other risk factors 1, 2:

High-Risk Features (Requires Cystoscopy + CT Urography)

• Age ≥60 years 1, 2
• Smoking history >30 pack-years 1, 2

• 25 RBCs/HPF on single urinalysis 1, 2

• Any history of gross hematuria 1, 2
• Occupational exposure to chemicals/dyes (benzenes, aromatic amines) 1, 2
• Irritative voiding symptoms without infection 1, 2
• History of pelvic irradiation 1
• Analgesic abuse 1

Intermediate-Risk Features (Cystoscopy + Imaging via Shared Decision-Making)

• Age 40-59 years 1, 2
• Smoking history 10-30 pack-years 1, 2
• 11-25 RBCs/HPF on single urinalysis 1, 2

Low-Risk Features (Repeat UA in 6 Months or Proceed with Evaluation Based on Patient Preference)

• Age <40 years 1, 2
• Never smoker or <10 pack-years 1, 2
• 3-10 RBCs/HPF on single urinalysis 1, 2
• No additional risk factors 1, 2

Step 5: Complete Urologic Evaluation (For Intermediate and High-Risk Patients)

Upper Tract Imaging

• Multiphasic CT urography is the preferred imaging modality for detecting renal cell carcinoma, transitional cell carcinoma, and urolithiasis 1, 2
• CT urography should include unenhanced, nephrographic phase, and excretory phase images 2
• Renal ultrasound alone is insufficient for comprehensive upper tract evaluation 1, 2
• Alternative imaging (MR urography or renal ultrasound with retrograde pyelography) may be used if CT is contraindicated due to renal insufficiency or contrast allergy 2

Lower Tract Evaluation

• Cystoscopy is mandatory for all males ≥40 years with microscopic hematuria and for any patient with high-risk features 1, 2
• Flexible cystoscopy is preferred over rigid cystoscopy due to less pain, fewer post-procedure symptoms, and equivalent or superior diagnostic accuracy 1, 2
• Cystoscopy allows direct visualization of bladder mucosa, urethra, and ureteral orifices 2

Additional Testing for High-Risk Patients

• Voided urine cytology should be obtained in high-risk patients to detect high-grade urothelial carcinomas and carcinoma in situ 1, 2

Step 6: Follow-Up Protocol

If Initial Evaluation is Negative but Hematuria Persists

• Repeat urinalysis at 6,12,24, and 36 months with blood pressure monitoring at each visit 1, 2
• Consider repeat complete evaluation within 3-5 years for persistent hematuria in high-risk patients 1, 2
• After two consecutive negative annual urinalyses, no further testing for asymptomatic microhematuria is necessary 2

Immediate Re-Evaluation is Warranted If:

• Gross hematuria develops 1, 2
• Significant increase in degree of microscopic hematuria 1, 2
• New urologic symptoms appear 1, 2
• Development of hypertension, proteinuria, or evidence of glomerular bleeding 1, 2

Critical Pitfalls to Avoid

• Never attribute hematuria solely to anticoagulation or antiplatelet therapy—these medications may unmask underlying pathology but do not cause hematuria, and evaluation should proceed regardless 1, 2
• Do not ignore any episode of gross hematuria, even if self-limited, as it carries a 30-40% risk of malignancy and requires urgent urologic referral 1, 2
• Do not delay evaluation in patients with high-risk features based on presumed benign causes—cancer-related hematuria can be intermittent 2
• Confirm microscopic hematuria before initiating extensive workup to avoid unnecessary procedures from false-positive dipstick results 1, 2