Urine Blood (BLD): Causes and Reference Range

What is urine blood (BLD)

Urine Blood (BLD) refers to red blood cells detected during a routine urinalysis. Normally, blood should be absent or present only in negligible amounts in urine. This marker is commonly assessed using a urine dipstick, while urine microscopy provides a more precise evaluation. The presence of blood in urine is called hematuria. It can be visible to the naked eye (macrohematuria) or detectable only by laboratory testing (microhematuria).

Reference ranges

Most laboratories report the result as negative (normal) or positive (requires attention). Quantitatively, a normal result is 0–3 red blood cells per high-power field on microscopy. A dipstick typically shows negative or trace.

Why urine blood levels may rise

A positive result may be associated with:

• Urinary tract infection (UTI) — the most common cause, especially in women.
• Kidney stones — mechanical injury to the urinary tract.
• Prostate disorders — in older men.
• Physical exertion — intense exercise can sometimes cause transient hematuria.
• Menstruation — can produce a false-positive result.
• Medications — anticoagulants.
• Glomerulonephritis — inflammation of the kidney glomeruli.

Rarer causes include bladder or kidney tumors.

Why the result may be falsely positive

Certain situations can produce a false-positive dipstick result:

• Myoglobinuria (following muscle injury)
• Highly concentrated urine
• Certain foods (beetroot)

If the dipstick result is positive, a doctor will typically order urine microscopy for confirmation.

What to do next

1. Do not panic — the most common cause is benign. 2. Repeat the test after 1–2 weeks. 3. Monitor for additional symptoms: pain, fever, or urinary difficulties. 4. See a doctor if the result is repeatedly positive.

Monitoring over time

A single positive finding often requires no further action. However, if red blood cells are detected in urine on multiple consecutive occasions, this is important information for your doctor. On the QbiLabs platform you can track this marker alongside other urinalysis results and kidney function indicators (creatinine, eGFR).

Questions to ask your doctor

• Blood was found in my urine — what additional tests should be considered?
• Could this be related to physical activity or medications?
• Should the test be repeated, and after how long?
• Would urine microscopy confirm the dipstick result?
• When should I be referred to a urologist or nephrologist?

*This is not medical advice. Consult your doctor for any health-related decisions.*