When a patient with sickle cell trait (SCT) presents with hematuria — visible (gross) or microscopic — the most important thing to remember is what not to do: do not attribute the bleeding to SCT until everything else has been ruled out.
That sounds obvious. In practice, it gets skipped, and the cost of skipping it can be enormous. Hematuria in SCT can occur because of papillary necrosis or microvascular changes in the renal medulla, but it can also herald renal medullary carcinoma (RMC) — a rare, aggressive cancer that occurs almost exclusively in patients with sickle hemoglobin (most often SCT) and that gets confused for benign trait-related bleeding. RMC's prognosis is dramatically better with early detection.
The workup. Treat hematuria in an SCT patient the same as in any patient — comprehensively.
- History and physical: trauma, infection, exercise pattern, hydration, family history of urologic malignancy, flank pain, weight loss.
- Urinalysis with microscopy to confirm red cells (and check for casts, crystals, infection).
- Urine culture if pyuria is present.
- Imaging: CT urogram or MRI for any patient with gross hematuria, persistent microscopic hematuria, flank pain, or risk factors. Don't skip imaging just because the patient has SCT.
- Cystoscopy when indicated by age, smoking history, or red flags.
- Referral to nephrology and/or urology for any unclear case.
Common alternative causes you should walk through systematically: intrinsic glomerular disease, urinary tract infection, nephrolithiasis, trauma, and malignancy.
Treatment when SCT is the cause. Most SCT-related hematuria responds to conservative measures — increased oral hydration, rest, activity restriction, and management of any underlying triggers. Refractory bleeding needs urology.
The teachable moment. Patients with SCT — especially young Black patients — have been historically underserved on this exact issue. A thorough workup and a conversation about RMC isn't fearmongering; it's standard of care. Then send them home with hydration counseling and a follow-up plan.
When in doubt, image. When still in doubt, refer.
— Dr. Rob
📄 Resource: CDC Sickle Cell Trait and Hematuria: Information for Healthcare Providers.