SUMMARY:

ACOG and AUGS released joint guidance on the screening and management of asymptomatic microscopic hematuria in women.  The data suggests that women at low risk for urinary tract malignancy (bladder, ureter and kidney) do not necessarily need follow up for asymptomatic microscopic hematuria.

Sample Collection

• Positive dipstick does not define asymptomatic microscopic hematuria but should generate a urinalysis and microscopic examination of urinary sediment
• A voided midstream sample is the recommended collection method for diagnosis
• Women have sex-specific risks for contamination (false positives) due to the following conditions
  • Menstruation
  • Urogenital atrophy
  • Pelvic organ prolapse

ACOG & AUGS

• No further evaluation required for low risk women that meet the following criteria (risk of malignancy ≤ 0.5%)
  • Asymptomatic
  • Never-smoking
  • Age 35 to 50
  • ≤ 25 red blood cells per high-power field
• As part of the Choosing Wisely Campaign (2020), AUGS continues to support limiting interventions and states

Asymptomatic hematuria in women is common but less likely to be associated with a urinary tract malignancy compared to men

Data support changing the evaluation requirements for microscopic hematuria in this low-risk group of women

Organizations which do not risk-stratify based on gender may continue to recommend more aggressive diagnostic evaluation in low-risk women

USPSTF

• No recommendation because current evidence is insufficient to assess the balance of benefits and harms of screening for bladder cancer in asymptomatic adults

AUA & SUFU

• AUA and SUFU define microhematuria as follows
  • ≥3 red blood cells per high powered field
  • Properly collected urinary specimen
• Positive dipstick does not define microhematuria but should generate a urinalysis and microscopic examination of urinary sediment
• Urine biomarkers (e.g., NMP22) are not recommended for use in routine evaluation
• Guidelines use a risk stratification algorithm to determine follow-up (low, intermediate or high risk)
  • Low risk: Women age <50 | Men age <40 yrs | Never smoker or <10 pack-years | 3 to 10 RBC/HPF on one UA | No additional risk factors for urothelial cancer1 No prior episodes of microhematuria
  • In the case of low risk microhematuria, the guideline states that 6 month follow up should be discussed with the patient in the context of shared decision making

…clinicians should discuss cystoscopy and imaging with renal ultrasound as options for evaluation, but should also review the option to repeat UA, with a plan to escalate to cystoscopy and imaging if the MH is found to persist

Key Points:

• Hematuria is associated with urinary tract malignancy and early detection of tumors with malignant potential could have an important effect on the mortality rate of bladder cancer (USPSTF)
• Risk factors for bladder cancer include:
  • Smoking
  • Occupational exposure to carcinogens (e.g., rubber, chemical, and leather industries)
  • Male sex
  • Older age
  • White race
  • Infections caused by certain bladder parasites (e.g., Schistosoma haematobium)
  • Family or personal history of bladder cancer
• Asymptomatic microscopic hematuria is common in women (ranges from 2.4% to 31.1%)
  • Less likely to be associated with urinary tract malignancy in women than men
  • ACOG and AUGS recommend that going forward, professional organizations produce sex-specific recommendations
• Harms associated with false positive screening results include
  • Anxiety
  • Unnecessary evaluations (e.g., CT radiation exposure) and treatments
  • Diagnostic-related from cystoscopy and biopsy
  • Overdiagnosis and overtreatment

Learn More – Primary Sources:

ACOG / AUGS Committee Opinion 703: Asymptomatic Microscopic Hematuria in Women

AUGS: Choosing Wisely Campaign

Microhematuria: AUA/SUFU Guideline

USPSTF: Bladder Cancer in Adults: Screening

Related ObG Topics: