Microscopic Hematuria Evaluation and Referral Guidelines

Definition and Diagnosis

Microscopic hematuria should be defined as >3 RBC/HPF on microscopic evaluation of a urinary specimen, as recommended by the American Academy of Family Physicians 1, 3
A positive dipstick test alone is insufficient for diagnosis and should always be confirmed with microscopic examination due to limited specificity (65-99%) 1
The initial determination should be based on microscopic examination of urinary sediment from a freshly voided, clean-catch, midstream urine specimen, according to the American Academy of Family Physicians 1, 2

Males with ≥3 RBC/HPF on microscopic evaluation of urinary sediment from two of three properly collected specimens should be referred to urology, as recommended by the American Academy of Family Physicians 1, 2
Some organizations now recommend proceeding with evaluation based on a single positive result on microscopic analysis due to the potential intermittent nature of hematuria from cancer, as suggested by the American College of Physicians 4, 5
High-risk patients should be considered for full urologic evaluation after one properly performed urinalysis documenting ≥3 RBC/HPF, according to the American Academy of Family Physicians 1, 2

Age >40 years is a risk factor that lowers the threshold for referral, as recommended by the American Academy of Family Physicians 1, 2
Smoking history is a risk factor that lowers the threshold for referral, according to the American Academy of Family Physicians 1, 2
History of gross hematuria is a risk factor that lowers the threshold for referral, as recommended by the American Urological Association 1, 6
Occupational exposure to chemicals or dyes (benzenes or aromatic amines) is a risk factor that lowers the threshold for referral, according to the American Academy of Family Physicians 1, 2

Patients on anticoagulants should be assessed in the same fashion as patients who are not on these medications, as recommended by the American Urological Association 3
Gross hematuria (visible blood in urine) requires immediate urologic referral regardless of RBC count due to high risk of malignancy (>10%), according to the American Urological Association 6