Isolated Hematuria

History of present illness includes duration of hematuria and any previous episodes. Urinary obstructive symptoms (eg, incomplete emptying, nocturia, difficulty starting or stopping) and irritative symptoms (eg, irritation, urgency, frequency, dysuria) should be noted. Patients should be asked about the presence of pain and its location and severity and whether they have vigorously exercised.

Review of systems should seek symptoms of possible causes, including joint pain and rashes (connective tissue disorder), and hearing loss or ocular manifestations (hereditary nephritis, also called Alport syndrome). Presence of fever, night sweats, or weight loss should also be noted.

Past medical history should include questions about any recent infections, particularly a sore throat that may indicate a group A beta-hemolytic streptococcal infection. Conditions known to cause urinary tract bleeding (particularly kidney calculi, sickle cell disease or trait, and glomerular disorders) should be sought, along with any history of congenital urinary tract anomalies. Also, conditions that predispose to a glomerular disorder, such as a connective tissue disorder (particularly systemic lupus erythematosus [SLE] and rheumatoid arthritis), endocarditis, shunt infections, and abdominal abscesses

Family history should identify relatives with known polycystic kidney disease, a glomerular disorder, or GU cancer. Patients should be asked about travel to areas where schistosomiasis is endemic, and tuberculosis risk factors should be assessed. Drug history should note use of anticoagulants, antiplatelet drugs (although controlled anticoagulation itself does not cause hematuria), and heavy analgesic use.

Vital signs should be reviewed for fever and hypertension.

The heart should be auscultated for murmurs (suggesting endocarditis).

The abdomen should be palpated for masses; flanks should be percussed for tenderness over the kidneys. In men, a digital rectal examination should be done to check for prostate enlargement, nodules, and tenderness.

The face and extremities should be inspected for edema (suggesting a glomerular disorder), and the skin should be inspected for rashes (suggesting vasculitis, SLE, or immunoglobulin A–associated vasculitis).

The following findings are of particular concern:

• Gross hematuria and concurrent proteinuria

• Persistent microscopic hematuria, especially in older patients

• Age > 50

• Hypertension and edema

• Systemic symptoms (eg, fever, night sweats, weight loss)

Clinical manifestations of the various causes overlap significantly, so urine and often blood tests are required. Depending on results, imaging tests may then be needed. However, some clinical findings provide helpful clues (see table Some Common Causes of Hematuria).

• Blood clots in urine essentially rule out a glomerular disorder. Glomerular disorders are often accompanied by edema, hypertension, or both; symptoms may be preceded by an infection (particularly a group A beta-hemolytic streptococcal infection in children).

• Calculi usually manifest with excruciating, colicky pain. Less severe, more continuous pain is more likely to result from infection, cancer, polycystic kidney disease, glomerulonephritis, and loin pain–hematuria syndrome.

• Urinary irritative symptoms suggest bladder or prostate infection but may accompany certain cancers (mainly bladder and prostate).

• Urinary obstructive symptoms usually suggest prostate disease.

• An abdominal mass suggests polycystic kidney disease or renal cell carcinoma.

• A family history of nephritis, sickle cell disease or trait, or polycystic kidney disease suggests that as a cause.

• Travel to Africa, the Middle East, or India suggests the possibility of schistosomiasis.

• Systemic symptoms (eg, fever, night sweats, weight loss) may indicate cancer or subacute infection (eg, tuberculosis [TB]) or an autoimmune (connective tissue) disorder.

On the other hand, some common findings (eg, prostate enlargement, excessive anticoagulation), although potential causes of hematuria, should not be assumed to be the cause without further evaluation.

Before testing proceeds, true hematuria should be distinguished from red urine by urinalysis. In women with vaginal bleeding, the specimen should be obtained by straight catheterization to avoid contamination by a nonurinary source of blood. Red urine without red blood cells (RBCs) suggests myoglobinuria or hemoglobinuria, porphyria, or ingestion of certain drugs or foods. Generally, the presence of hematuria should be confirmed by testing a 2nd specimen.

Presence of casts, protein, or dysmorphic RBCs (unusually shaped, with spicules, folding, and blebs) indicates a glomerular disorder. White blood cells or bacteria suggest an infectious etiology. However, because urinalysis shows predominantly RBCs in some patients with cystitis, urine culture is usually done. A positive culture result warrants treatment with antibiotics. If hematuria resolves after treatment and no other symptoms are present, no further evaluation is required for patients < 50, especially women.

If patients < 35 (including children) have only microscopic hematuria and no urine findings suggesting a glomerular disorder, no clinical manifestations suggesting a cause, no risk factors for cancer, and an identified benign cause (eg, infection, mild trauma), they can be observed, with urinalysis repeated every 6 to 12 months. If a benign cause is not evident or hematuria is persistent, testing is indicated (1), beginning with ultrasonography or CT with contrast, sometimes followed by cystoscopy.

Patients < 50 with gross hematuria or unexplained systemic symptoms require ultrasonography or CT of the abdomen and pelvis.

If urine or clinical findings suggest a glomerular disorder, renal function is evaluated by measuring blood urea nitrogen, serum creatinine, and electrolytes; doing a urinalysis; and periodically determining the urine protein/creatinine ratio. Further evaluation of a glomerular disorder may require serologic tests, kidney biopsy, or both.

All patients ≥ 35 require cystoscopy, as do patients who are < 35 but have risk factors, such as a family history of cancer, or systemic symptoms (1). Men ≥ 50 require discussion of testing for prostate-specific antigen through shared decision-making; those with elevated levels require further evaluation for prostate cancer.

1. 1. Barocas DA, Boorjian ST, Alvarez RD, et al: Microhematuria: AUA/SUFU guideline. J Urol 204(4):778-786, 2020. doi: 10.1097/JU.0000000000001297