Initial Workup for Hematuria

Classification and Initial Assessment

The American Academy of Family Physicians recommends that the initial workup for hematuria should include urinalysis with microscopic examination, laboratory tests to assess renal function, and appropriate imaging based on risk stratification, followed by cystoscopy in high-risk patients or those with persistent unexplained hematuria 1, 2
Microscopic hematuria is defined as ≥3 red blood cells per high-power field on microscopic evaluation of urinary sediment from at least two of three properly collected urinalysis specimens, according to the American Academy of Family Physicians 3
The American Academy of Family Physicians suggests that dipstick positive results should always be confirmed with microscopic examination due to limited specificity (65-99%) 3
Initial assessment should rule out benign causes including infection, vigorous exercise, menstruation, sexual activity, trauma, and certain medications, as recommended by the American Academy of Family Physicians 4, 5

The American College of Radiology states that gross hematuria carries a high risk of malignancy (30-40%) and requires urgent urologic referral regardless of other factors, although this specific fact is from Praxis Medical Insights, a similar fact from the American College of Radiology is that male gender is a risk factor for significant urologic disease 2
Risk factors for significant urologic disease include age >40 years, as recommended by the American Academy of Family Physicians 4
Smoking history is a risk factor for significant urologic disease, according to the American College of Radiology 2
Occupational exposure to chemicals or dyes is a risk factor for significant urologic disease, as stated by the American Academy of Family Physicians 4

The American Academy of Family Physicians recommends that complete urinalysis with microscopic examination should assess the number of red blood cells per high-power field, presence of dysmorphic red blood cells or red cell casts, presence and degree of proteinuria, and evidence of urinary tract infection 4
Serum creatinine should be measured to assess renal function, as recommended by the American Academy of Family Physicians 4

Glomerular source indicators include significant proteinuria (>500 mg/24 hours), dysmorphic red blood cells, red cell casts, and elevated serum creatinine, according to the American Academy of Family Physicians and the American College of Radiology 2, 4, 5
Non-glomerular (urologic) source indicators include normal-shaped RBCs, minimal or no proteinuria, and normal serum creatinine, as stated by the American College of Radiology 2, 5

The American College of Radiology recommends that for patients with gross hematuria or microscopic hematuria with risk factors, CT urography is the preferred imaging modality for comprehensive evaluation of the upper urinary tract 2
For children or low-risk patients with microscopic hematuria, renal and bladder ultrasound is the appropriate first-line imaging test, according to the American College of Radiology 7, 8

The American Academy of Family Physicians recommends that cystoscopy is indicated for all patients with gross hematuria, patients ≥40 years with microscopic hematuria, and patients <40 years with risk factors for bladder cancer 1
Flexible cystoscopy is preferred over rigid cystoscopy due to less pain, fewer post-procedure symptoms, and at least equivalent diagnostic accuracy, as stated by the American Academy of Family Physicians 1

Urologic referral is necessary for all patients with gross hematuria, patients with microscopic hematuria and risk factors for malignancy, and patients with persistent unexplained hematuria, according to the American Academy of Family Physicians and the American College of Radiology 1, 2, 4, 6
Nephrology referral is recommended if there is evidence of glomerular disease, as stated by the American Academy of Family Physicians 4, 5

For patients with a negative initial evaluation of asymptomatic microscopic hematuria, repeat urinalysis, urine cytology, and blood pressure determination at 6, 12, 24, and 36 months, as recommended by the American Academy of Family Physicians 1
Additional evaluation including repeat imaging and cystoscopy may be warranted in patients with persistent hematuria, according to the American Academy of Family Physicians 1

Do not attribute hematuria solely to antiplatelet or anticoagulant medications without further investigation, as stated by the American Academy of Family Physicians and the American College of Radiology 1, 2, 6
Do not assume BPH or hypertension is the cause of hematuria without proper evaluation, according to the American Academy of Family Physicians 1, 9
Do not delay urologic referral for patients with gross hematuria while waiting for other test results, as recommended by the American College of Radiology 2, 6
Do not rely solely on dipstick results without microscopic confirmation, according to the American Academy of Family Physicians 3