From the Guidelines
Red flags for hematuria include gross hematuria, hematuria with pain, age over 35 years, smoking history, occupational exposure to chemicals, history of pelvic irradiation, and recent urologic procedures, which warrant urgent evaluation due to the association with urological malignancies. These factors are identified as high-risk characteristics that necessitate prompt referral to urology for further investigation, including cystoscopy and upper tract imaging 1. The presence of these red flags indicates a potential for serious underlying conditions, such as bladder or kidney cancer, where early detection significantly improves outcomes.
Key red flags for hematuria are:
- Gross hematuria (visible blood in urine)
- Hematuria with pain
- Age over 35 years
- Smoking history
- Occupational exposure to chemicals or dyes
- History of pelvic irradiation
- Recent urologic procedures
- Persistent hematuria despite treatment of initial causes
- Hematuria with clots
- Hematuria with constitutional symptoms (weight loss, fatigue)
- Hematuria in the setting of anticoagulant therapy or bleeding disorders
When these red flags are present, prompt referral to urology is recommended with consideration of cystoscopy and upper tract imaging 1. Even microscopic hematuria should not be dismissed, especially when persistent or accompanied by these red flags, as it may be the earliest sign of serious urological disease 1. The evaluation of hematuria should be pursued even if the patient is receiving antiplatelet or anticoagulant therapy 1.
It is essential to consider the patient's overall clinical presentation and risk factors when evaluating hematuria, rather than relying solely on the presence or absence of blood in the urine. By prioritizing the evaluation of high-risk patients and promptly referring them to urology, clinicians can improve outcomes and reduce the morbidity and mortality associated with urological malignancies.
From the Research
Hematuria Red Flags
- Hematuria is a common condition that can be classified as either gross or microscopic, and it warrants a thorough history and physical to determine potential causes and assess risk factors for malignancy 2
- Red flags for hematuria include painless gross hematuria (PGH) and asymptomatic microhematuria (AMH), which can indicate a higher risk of urologic malignancy 3
- Patients with PGH are more likely to undergo urologic referral and cystoscopy, and have a higher rate of bladder neoplasms detection compared to those with AMH 3
- The presence of red flags, such as hematuria, can indicate a possible serious underlying condition, and evaluation of these red flags is crucial in primary care to minimize the risk of missing serious diseases 4
- Chronic kidney disease (CKD) is also a risk factor for kidney or urothelial malignancy, and patients with CKD should be considered for evaluation for the presence and etiology of hematuria 5
Evaluation of Hematuria
- A focused history and physical, including laboratory studies and diagnostic imaging, is essential in evaluating patients with hematuria 6
- The cause of hematuria can originate in the genitourinary tract, and patients can be discharged with close outpatient follow-up if they remain stable 6
- However, delays in evaluation for hematuria can occur, and many of these delays are preventable with interventions such as EHR-based tracking systems or reformed scheduling practices 3
Risk Factors for Malignancy
- The risk of malignancy with gross hematuria is greater than 10%, and prompt urologic referral is recommended 2
- CKD is associated with a higher risk of kidney cancer and urothelial carcinoma, and patients with CKD should be considered for evaluation for the presence and etiology of hematuria 5
- The presence of red flags, such as PGH or AMH, can indicate a higher risk of urologic malignancy, and patients with these red flags should be evaluated promptly 3