Hematuria

Evaluation of Hematuria

Classification

• Microscopic Hematuria: $\ge 3$ RBCs/hpf on microscopic UA.
• Gross Hematuria: Visually blood-stained urine (pink, red, or tea-colored).
• Glomerular vs. Non-Glomerular (Urological):
  • Glomerular:
    • Dysmorphic RBCs (acanthocytes) & RBC casts.
    • Brown, “cola-colored” urine.
    • Proteinuria >500 mg/day.
    • No blood clots (urinary tract enzymes lyse them, or bleeding is too slow).
  • Non-Glomerular:
    • Isomorphic (normal shape) RBCs, no casts.
    • Bright red/pink urine.
    • Blood clots may be present (highly suggestive of urological origin).
    • Proteinuria <500 mg/day.

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Diagnostic Algorithm

1. Initial Screen: Dipstick positive for blood.
2. Confirmation: Microscopic UA (rules out false positives from myoglobinuria/hemoglobinuria).
3. Evaluate for Benign Causes:
   • UTI, menstruation, vigorous exercise, trauma, recent urological instrumentation.
   • If UTI present -> treat UTI and repeat microscopic UA in 3–6 weeks.
4. Stratify & Workup (No Benign Cause Identified):
   • If Glomerular Features -> order BMP, spot urine protein/Cr ratio, complement levels (C3, C4), ANA, ANCA, anti-GBM. Refer to nephrology for potential renal biopsy.
   • If Non-Glomerular Features -> Risk stratify for malignancy:
     • High Risk (e.g., gross hematuria, age >35 + smoker): CT Urography (CTU) + Cystoscopy.
     • If contrast contraindicated (CKD, contrast allergy): Renal Ultrasound or Non-contrast CT + Cystoscopy (often combined with retrograde pyelogram).