23-02: Hematuria

An upper tract source (kidneys and ureters) can be identified in 10% of patients with gross or microscopic hematuria. For upper tract sources, stone disease accounts for 40%, medical kidney disease (medullary sponge kidney, glomerulonephritis, papillary necrosis) for 20%, renal cell carcinoma for 10%, and urothelial cell carcinoma of the ureter or renal pelvis for 5%. Medication ingestion and associated medical problems may provide diagnostic clues. Analgesic use (papillary necrosis), cyclophosphamide (chemical cystitis), antibiotics (interstitial nephritis), diabetes mellitus, sickle cell trait or disease (papillary necrosis), a history of stone disease, or malignancy should all be investigated. The lower tract source of gross hematuria (in the absence of infection) is most commonly from bleeding prostatic varices or urothelial carcinoma of the bladder. Microscopic hematuria in the male is most commonly from benign prostatic hyperplasia (13%), kidney stones (6%), or urethral stricture (1.4%). The presence of hematuria in patients receiving antiplatelet or anticoagulation therapy cannot be presumed to be due to the medication; a complete evaluation is warranted consisting of upper tract imaging, cystoscopy, and urine cytology (see Chapter 39 for Bladder Cancer, Cancers of the Ureter & Renal Pelvis, Renal Cell Carcinoma, and Other Primary Tumors of the Kidney).

A. Symptoms and Signs

If gross hematuria occurs, a description of the timing (initial, terminal, total) may provide a clue to the localization of disease. Associated symptoms (ie, renal colic, irritative voiding symptoms, or constitutional symptoms) should be investigated. Physical examination should look for signs of systemic disease (fever, rash, lymphadenopathy, abdominal or pelvic masses) as well as signs of medical kidney disease (hypertension, volume overload). Urologic evaluation may demonstrate an enlarged prostate, flank mass, or urethral disease.

B. Laboratory Findings

Initial laboratory investigations include a urinalysis and urine culture. Microhematuria is defined as three or more red blood cells per high-power field on a microscopic evaluation of the urine. A positive dipstick reading for heme merits microscopic examination to confirm or refute the diagnosis of hematuria but is not enough to warrant workup on its own. If urinalysis and culture is suggestive of a urinary tract infection, follow-up urinalysis after treatment of the infection is important to ensure resolution of the hematuria. An estimate of kidney function should be obtained since renal insufficiency may influence the methods of further evaluation and management (eg, ability to obtain contrast imaging) of patients with hematuria. Urine cytology and other urinary-based markers are not routinely recommended in the evaluation of asymptomatic microscopic hematuria.

C. Imaging

The upper tract should be imaged using a CT-intravenous pyelogram (CT-IVP), which is an abdominal and pelvic CT scan without contrast, with contrast, and with excretory delayed imaging. These phases are necessary to identify neoplasms of the kidney or ureter as well as benign conditions such as urolithiasis, obstructive uropathy, papillary necrosis, medullary sponge kidney, or polycystic kidney disease. For patients with relative or absolute contraindications that preclude a CT-IVP (such as kidney dysfunction, intravenous contrast allergy, or pregnancy), a magnetic resonance urogram without and with contrast can be performed. The role of ultrasonographic evaluation of the urinary tract for hematuria is unclear. Although it may provide adequate information for the kidney, its sensitivity in detecting ureteral disease is lower.

D. Cystoscopy

Cystoscopy is necessary to assess for bladder or urethral neoplasm, benign prostatic hyperplasia, and radiation or chemical cystitis; it is indicated for patients with gross hematuria and those over age 35 years with asymptomatic microscopic hematuria.

In patients with negative hematuria evaluations, it is typically recommended that a urinalysis with microscopy be repeated at 6–12 months. If two consecutive annual urinalyses are negative for hematuria (one per year for 2 years), then no further urinalyses are required. If microscopic hematuria persists on annual urinalyses, then repeat evaluation with cystoscopy and upper tract imaging should be considered within 3–5 years. Recurrent gross hematuria may require repeat evaluation with cystoscopy and upper tract imaging 1 year after initial negative evaluation. Urinary cytology may be obtained by the urologist after initial negative evaluation or in persons with risk factors (irritative voiding symptoms, tobacco use, chemical exposures).

In the absence of a clear benign etiology (such as an infection, menstruation, vigorous exercise, acute stone event, medical renal disease, viral illness, trauma, or recent urologic procedure), hematuria (either gross or microscopic) requires evaluation.