What are the next steps for a patient with a urine dip showing a small amount of non-hemolyzed blood, indicating hematuria?

Confirm True Hematuria with Microscopic Urinalysis Before Any Workup

A urine dipstick showing "small amount non-hemolyzed blood" requires microscopic confirmation with ≥3 RBCs per high-power field on at least two of three properly collected clean-catch midstream specimens before initiating any further evaluation. 1, 2

Why Dipstick Alone Is Insufficient

• Dipstick testing has limited specificity (65-99%) and measures peroxidase activity, which produces false positives from myoglobinuria, hemoglobinuria, povidone iodine, dehydration, and certain medications. 1, 2
• The American College of Physicians explicitly states that "a dipstick reading suggestive of hematuria should not lead to imaging or further investigation without confirmation of three or greater red blood cells per high power field." 1
• Relying on dipstick alone without microscopic confirmation is a common pitfall that leads to unnecessary workup, patient anxiety, invasive testing, radiation exposure, and costs. 2

Immediate Next Steps

1. Obtain Microscopic Urinalysis

• Request microscopic examination of a properly collected clean-catch midstream urine specimen to quantify RBCs per high-power field. 1, 2
• Microscopic hematuria is defined as ≥3 RBCs/HPF, and this threshold must be met on at least 2 of 3 specimens before proceeding with extensive urologic workup. 1, 3
• High-risk patients (age >35-40 years, smoking history, occupational chemical exposure, history of gross hematuria, or irritative voiding symptoms) may warrant full evaluation after a single properly performed urinalysis showing ≥3 RBCs/HPF. 1, 2

2. Examine Urinary Sediment for Key Features

• Assess for dysmorphic RBCs (>80% suggests glomerular origin), red cell casts (pathognomonic for glomerular disease), white blood cells, bacteria, crystals, and degree of proteinuria. 1, 3
• Document the percentage of dysmorphic RBCs to differentiate between glomerular and non-glomerular sources. 1

3. Exclude Transient Benign Causes

• Recent vigorous exercise, sexual activity, menstruation, viral illness, or minor trauma can cause self-limited hematuria. 1
• If history suggests transient causes, repeat urinalysis 48 hours after cessation of the activity—no further evaluation is needed if hematuria resolves. 1
• In women, perform urethral and vaginal examination to exclude local contamination, and obtain catheterized specimen if clean-catch is unreliable. 1

If Microscopic Hematuria Is Confirmed (≥3 RBCs/HPF)

Risk Stratification for Malignancy

• High-risk features include: males ≥60 years, females ≥60 years, smoking history >30 pack-years, >25 RBCs/HPF, any history of gross hematuria, occupational exposure to benzenes/aromatic amines, or irritative voiding symptoms without infection. 1, 4
• Intermediate-risk features include: males 40-59 years, females <60 years, smoking history 10-30 pack-years, or 11-25 RBCs/HPF. 1
• Low-risk features include: males <40 years, never smoker or <10 pack-years, and 3-10 RBCs/HPF. 1

Complete Urologic Evaluation for High-Risk Patients

• Multiphasic CT urography is the preferred imaging modality for detecting renal cell carcinoma, transitional cell carcinoma, and urolithiasis—includes unenhanced, nephrographic, and excretory phases. 1, 4, 3
• Cystoscopy is mandatory for all patients with gross hematuria and for microscopic hematuria patients with high-risk features—flexible cystoscopy is preferred over rigid due to less pain and equivalent diagnostic accuracy. 1, 4, 3
• Serum creatinine should be measured to assess renal function and identify potential medical renal disease. 1, 4
• Urine culture should be obtained if infection is suspected (preferably before antibiotics), but infection does not explain hematuria without follow-up confirmation after treatment. 1, 4

Nephrology Referral Indications

• Refer to nephrology if significant proteinuria (protein-to-creatinine ratio >0.5 g/g), dysmorphic RBCs >80%, red cell casts, elevated creatinine, or hypertension with hematuria are present—these suggest glomerular disease. 1, 3
• The presence of glomerular features does NOT eliminate the need for urologic evaluation, as malignancy can coexist with medical renal disease. 1

Critical Pitfalls to Avoid

• Never ignore gross hematuria, even if self-limited—it carries a 30-40% malignancy risk and mandates urgent urologic referral. 1, 4
• Do not attribute hematuria to anticoagulation or antiplatelet therapy—these medications may unmask underlying pathology but do not cause hematuria themselves, and evaluation should proceed regardless. 1, 4, 3
• Do not rely solely on dipstick results without microscopic confirmation—this is the most common error in hematuria evaluation. 1, 2
• Do not delay referral based on medication history—if microscopic hematuria is confirmed in high-risk patients, proceed with full evaluation. 2

Follow-Up Protocol for Negative Initial Evaluation

• If initial workup is negative but hematuria persists, repeat urinalysis, voided urine cytology (in high-risk patients), and blood pressure monitoring at 6,12,24, and 36 months. 1, 4
• After two consecutive negative annual urinalyses, no further testing for asymptomatic microhematuria is necessary. 1
• Immediate re-evaluation is warranted if gross hematuria develops, significant increase in microscopic hematuria occurs, new urologic symptoms appear, or development of hypertension, proteinuria, or evidence of glomerular bleeding. 1, 4