What Causes High Leukocytes in Urine and How Do Doctors Treat it?

Elevated leukocytes, a form of white blood cell, in urine can signal a urinary tract infection, kidney stones, or other underlying issues. The appropriate management will vary depending on the root cause.

Increased leukocyte counts may be detected on a complete blood count (CBC) or via a urinalysis, which examines a urine specimen.

Generally, a raised white blood cell (WBC) count in the blood indicates inflammation somewhere in the body, while an elevated WBC count in urine points more specifically to the urinary system.

If your urinalysis reveals an elevated leukocyte level, your clinician may order further investigations to pinpoint the cause. Follow up with the healthcare provider who requested the urine test for additional evaluation.

This article explores leukocytes, their role, what it implies if they are high in urine, and when to consult a doctor about your findings.

What are leukocytes?

Leukocytes are white blood cells produced by the body as part of its immune response to infection or other foreign presences.

There are several types of WBCs, including neutrophils and basophils, and each type contributes to immune defenses. When an infection or other unwanted factor occurs in a particular area, WBCs migrate there to address it.

Consequently, elevated leukocyte counts may indicate an infectious process.

A blood test can show high leukocyte levels circulating in the bloodstream, but if the problem involves the urinary tract, tests may reveal increased leukocytes in the urine.

High leukocyte counts in urine may point to an infection in the bladder or urethra, the tube that expels urine from the bladder. They can also reflect a kidney infection, though noninfectious factors like kidney stones can raise leukocyte counts as well.

Why might leukocytes appear in your urine?

Elevated leukocytes in urine can arise from:

• a urinary tract infection (UTI)
• a kidney infection or kidney stones
• an obstruction in the urinary tract or bladder
• a pelvic tumor
• certain medications

Pregnancy increases the risk of UTIs. Prompt treatment during pregnancy is important because UTIs can lead to complications.

Delaying urination for extended periods can also raise the likelihood of a UTI. When urine remains in the bladder too long, bacteria can multiply and result in a bladder infection.

Some conditions prevent the bladder from emptying fully, which increases the risk of UTI because urine stagnates. This can be evaluated by measuring the post-void residual (PVR) volume with ultrasound. In such cases, addressing the infection alone is insufficient — the underlying cause of the elevated PVR must also be treated.

Having high WBCs in urine without bacteria present is called sterile pyuria. It can be caused by several factors, such as tuberculosis (TB), certain sexually transmitted infections (STIs), cystitis, bladder cancer, and autoimmune disorders like systemic lupus erythematosus (SLE).

Certain medications can also elevate leukocyte levels.

Examples include:

• nonsteroidal anti-inflammatory drugs (NSAIDs)
• steroids
• proton-pump inhibitors (PPIs), such as omeprazole, which reduce stomach acid
• some antibiotics

The presence of a tumor or receiving cancer therapy in the pelvic region may also weaken immune defenses, raising susceptibility to infections and increasing leukocyte counts.

What are the symptoms of leukocytes in your urine?

When leukocytes appear in urine, symptoms will reflect the underlying condition that caused their increase.

UTI symptoms

Common signs of a UTI include:

• a frequent need to urinate
• a burning feeling during urination
• cloudy or pinkish urine
• a strong or unpleasant urine odor
• pelvic discomfort

Symptoms of an obstruction

Symptoms of a blockage vary with its location and nature.

Blockages can be in the lower tract, such as the urethra or prostate, leading to urine retention (elevated PVR), which often causes UTIs. Upper tract blockages can occur in the ureters or kidneys and may result from stones, congenital narrowing, or tumors.

Pain is a frequent symptom of obstruction and may affect one or both sides of the abdomen. Kidney stone obstructions can produce severe pain, nausea, and vomiting. If you have signs of an obstruction, seek emergency care.

What tests determine the cause of high urine leukocytes?

Even otherwise healthy people can have elevated leukocytes in blood and urine. Leukocytosis in blood indicates inflammation somewhere in the body, while leukocytosis in urine signifies inflammation in the urinary tract.

• A typical blood range is about 4,000–11,000 WBCs per microliter (µl).
• Leukocyte counts in urine are generally expected to be 10 cells per microliter or less.

If a clinician suspects a UTI or kidney stones, they will likely request a urine sample to test for:

• WBCs
• red blood cells
• bacteria
• other substances

If kidney stones are involved, crystals may appear in the urine, prompting further imaging such as ultrasound or CT scan.

If results show elevated WBCs in urine, inflammation is likely. This may indicate a bacterial infection depending on symptoms and whether bacteria and/or nitrites (a byproduct of certain bacteria) are detected.

A urine culture can confirm a bacterial infection and identify the responsible organism.

A clinician may also order an X-ray or CT to check for stones.

How do doctors treat high leukocyte levels in your urine?

Treatment is determined by the underlying cause of elevated leukocytes.

For a UTI, antibiotics and increased fluid intake are commonly recommended. Home measures can also help relieve bladder infection symptoms.

For upper tract obstructions (in ureters or kidneys), options may include:

• drinking plenty of fluids to help pass small kidney stones
• a shock wave procedure to fragment stones
• surgical removal of a large stone

Lower tract obstructions (bladder or urethra) may require other interventions.

If a tumor is responsible for the blockage, further evaluation and treatment such as surgery, chemotherapy, radiation, or combinations thereof may be necessary.

Optum Now is operated by RVO Health. By clicking on this link, we may receive a commission. Learn more.

How can you prevent high leukocyte levels in your urine?

Measures to reduce urinary tract problems include:

• drinking ample fluids
• wiping from front to back after using the toilet
• cleaning the genital area before and after sex and drying thoroughly
• urinating soon after sexual activity
• changing incontinence pads frequently, if used
• seeking prompt evaluation for changes in urine color, odor, pain during urination, or pelvic discomfort
• finishing prescribed antibiotics as directed, even if symptoms improve, to help prevent recurrence

Some evidence suggests that cranberry juice or cranberry products may help prevent UTIs in certain people. You can also read about natural options in herbs for uti for complementary approaches to UTI prevention.

What’s the outlook for people with high leukocyte levels in their urine?

With timely diagnosis and treatment, UTIs and kidney stones are usually resolvable, though they can recur.

Both benign and malignant tumors can occur, and appropriate testing will guide the necessary therapy.

Cancers are treatable, but the options depend on many factors, including how far the disease has progressed.

Frequently asked questions about high leukocyte levels

Can you have leukocytes in urine but no UTI?

Yes. Sterile pyuria can occur with autoimmune disorders and bladder cancer. Certain drugs, such as NSAIDs, steroids, PPIs, and some antibiotics, can also raise leukocyte levels in urine.

Do leukocytes in urine only mean UTI?

Elevated WBCs in urine can indicate various infections but may also point to obstructions, different health conditions, or the effects of certain medications.

What can cause leukocytes in urine besides UTI?

Other causes include benign or malignant tumors, kidney stones, tuberculosis, some STIs, autoimmune diseases like systemic lupus erythematosus, and certain cancers. Various medications may also elevate leukocyte counts in urine.

Are leukocytes in urine serious?

High leukocyte or WBC levels in urine commonly indicate the body is combating an infection, often a UTI.

However, they can also reflect more serious noninfectious issues such as kidney stones or a pelvic tumor.

Takeaway

Elevated leukocytes or white blood cells in urine commonly suggest an infection, but other causes — including kidney stones or benign or malignant growths — may be responsible.

Seek prompt evaluation for pelvic pain, urinary discomfort, or any changes in urination, since complications can develop if the underlying cause of elevated urinary leukocytes is not treated.