What is the appropriate workup and management for asymptomatic microscopic hematuria (blood in urine)?

From the Guidelines

All patients with microscopically confirmed hematuria in the absence of a demonstrable benign cause should undergo cystoscopy and imaging, as recommended by the American College of Physicians 1. The initial evaluation of microscopic hematuria should include a comprehensive history, physical examination, and repeat urinalysis to confirm persistence. The definition of microscopic hematuria is three or more red blood cells per high-power field on microscopic evaluation of urinary sediment from two of three properly collected urinalysis specimens, as defined by the American Urological Association 1. Key considerations in the workup of microscopic hematuria include:

• Cystoscopy for patients over 35 years old or those with risk factors for bladder cancer, such as smoking history, chemical exposures, or prior pelvic radiation 1
• Upper tract imaging with CT urography for patients with persistent microscopic hematuria without an obvious benign cause 1
• Laboratory tests, including serum creatinine, estimated glomerular filtration rate, and urine culture, to evaluate for potential underlying conditions such as glomerulonephritis or urinary tract infection 1
• Nephrology consultation for patients with suspected glomerular disease, based on proteinuria, dysmorphic RBCs, or RBC casts 1 The management of microscopic hematuria depends on the underlying cause, with urologic conditions potentially requiring surgical intervention and glomerular causes potentially requiring immunosuppressive therapy. Patients with negative evaluations should have repeat urinalysis at 6,12, and 24 months, with reconsideration of the complete workup if hematuria persists, as the condition can be the first sign of serious conditions including malignancy, urolithiasis, or glomerulonephritis, though in approximately 70% of cases no specific cause is identified after complete evaluation 1.

From the Research

Microscopic Hematuria Workup

• The initial evaluation of microscopic hematuria should include renal ultrasound (US) and cystoscopy, along with urinalysis, urine culture, and cytology 2
• Patients with proteinuria, red cell casts, and elevated serum creatinine levels should be referred promptly to a nephrology subspecialist 3
• Microscopic hematuria with signs of urinary tract infection should resolve with appropriate treatment of the underlying infection 3

Management of Persistent Microscopic Hematuria

• Patients with persistent microhematuria after 3 months without definite etiology of the bleeding may still benefit from intravenous urography (IVU) 2
• The combination of cytology plus intravenous urography, computed tomography, or ultrasonography can be used to evaluate patients with asymptomatic microscopic hematuria or with hematuria persisting after treatment of urinary tract infection 3
• When urine cytology results are abnormal, cystoscopy should be performed to complete the investigation 3

Diagnostic Findings

• Abnormalities found in patients with persistent microhematuria may include renal stones, ureteral stones, ureteral tumors, and tumors of the renal pelvis 2
• The use of IVU in patients with resolved microhematuria is not necessary, as studies have shown that these patients have normal IVU results 2