ESSENTIALS OF DIAGNOSIS
Both gross and microscopic hematuria require evaluation.
The upper urinary tract should be imaged, and cystoscopy should be performed if there is hematuria in the absence of an identifiable benign cause.
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 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 Chapters 39-18, 39-19, 39-20 and 39-21 for Bladder Cancer, Cancers of the Ureter & Renal Pelvis, Renal Cell Carcinoma, and Other Primary Tumors of the Kidney).
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, constitutional symptoms) should be investigated. Physical examination should emphasize 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.
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. If hematuria is present, proteinuria, dysmorphic red blood cells, and urinary casts suggest renal origin. Irritative voiding symptoms, bacteriuria, and a positive urine culture suggest urinary tract infection, but follow-up urinalysis is important after treatment to ensure resolution of the hematuria. An estimate of kidney function should be obtained, since intrinsic kidney disease has implications for further evaluation and management of patients with hematuria. Urine cytology and other urinary-based markers are not routinely recommended in the evaluation of asymptomatic microscopic hematuria.
The upper tract should be imaged using a CT-intravenous pyelogram (CT-IVP), which is an ...