From the Guidelines
The evaluation of hematuria without kidney stones requires a systematic approach to identify the underlying cause, with initial assessment including a complete history and physical examination, laboratory tests, and imaging studies, as recommended by the most recent guidelines 1. The approach should start with a thorough history and physical examination, followed by laboratory tests including urinalysis with microscopy, urine culture, complete blood count, and renal function tests.
- Imaging studies are essential, starting with renal ultrasound and potentially advancing to CT urography if needed, as suggested by the American College of Radiology 1.
- Cystoscopy is recommended for all patients over 35 years with microscopic hematuria and for any patient with gross hematuria to evaluate the bladder and urethra for lesions, according to the American Urological Association guidelines.
- Risk factors for malignancy such as smoking history, chemical exposures, and age over 50 should prompt more aggressive evaluation, as highlighted by the American College of Physicians 1.
- If initial workup is negative but hematuria persists, referral to a urologist is warranted for further specialized assessment.
- For patients with infection-related hematuria, appropriate antibiotics should be prescribed based on culture results, typically for 7-14 days.
- Patients with glomerular causes of hematuria may require nephrology consultation.
- Follow-up urinalysis should be performed 4-6 weeks after treatment to confirm resolution. This comprehensive approach is necessary because hematuria can signal serious conditions including malignancy, infection, or glomerular disease, and early diagnosis improves outcomes, as emphasized by the latest updates to microhematuria guidelines 1.
From the Research
Evaluation Approach
The evaluation of a patient with hematuria and no evidence of kidney stones involves a thorough history and physical examination, measurement of inflammatory parameters and renal function tests, and ultrasonography of the kidneys and bladder 2. A risk-adapted diagnostic strategy for the evaluation of asymptomatic microhematuria (aMH) is presented, which includes urethrocystoscopy, urine cytology, and, when indicated, CT urography for patients with non-glomerular aMH who have risk factors such as smoking, advanced age, and male sex.
Diagnostic Tools
- Ultrasonography: to evaluate the kidneys and bladder 2
- CT urography: a comprehensive contrast material-enhanced multi-detector row computed tomography (CT) protocol that combines unenhanced, nephrographic-phase, and excretory-phase imaging 3, 4
- Urine microscopy: to detect erythrocytes and differentiate glomerular from non-glomerular hematuria 2, 5
- Urine cytology: to detect urothelial disease 2, 3
Management Approach
The management of hematuria involves resolving or preventing the underlying disorder, as there is no specific treatment to resolve or prevent hematuria 5. Persistent microscopic hematuria indicates the presence of a renal disease that warrants close monitoring and evaluation. Prompt referral to a pediatric nephrologist is indicated in situations when hematuria does not resolve within 2 weeks of onset of glomerulonephritis, there is a need for a renal biopsy, in the presence of persistent microscopic hematuria, and need for specific urine biochemistry testing or imaging studies 5.
Risk Factors and Prognosis
Patients with non-glomerular aMH who have risk factors such as smoking, advanced age, and male sex are more likely to have relevant underlying conditions and should therefore undergo augmented, risk-adapted diagnostic evaluation 2. Young persons with persistent isolated microscopic hematuria have an increased risk for end-stage kidney disease, mainly secondary to primary glomerular diseases such as IgA nephropathy, thin basement membrane disease, and Alport syndrome 6.