If your doctor tells you a routine urine test shows leukocytes, a type of white blood cell, hearing that news may be alarming or confusing. Leukocytes in urine may mean you have a high white blood cell count from an infection, or in rare cases, it may be an early sign of cancer.
In most cases, leukocytes in urine don’t indicate a major health issue and might simply mean you need your doctor to prescribe antibiotics or other medicine. But because it may be something more serious, including cancer, it’s critical to have a doctor evaluate the source and recommend next steps.
“An elevated white blood cell count is common and is way more often caused by a reactive process than by cancer,” says Tulio E. Rodriguez, M.D., a hematologist-oncologist and director of the Bone Marrow Transplantation and Cellular Therapy Program at City of Hope® Cancer Center Chicago.
“Infections, inflammation, a physical or emotional stress, smoking, using corticosteroids, pregnancy and even obesity are among the most frequent causes. However, a persistently elevated white blood cell count, without a clear cause, may signal a disease of the blood, including leukemia or myeloproliferative disorders.”
This article discusses the basics of leukocytes in urine, including:
- What is a high white blood cell count?
- When to worry about white blood cells in urine
- When are white blood cells in urine cancer?
- When to call a doctor: What to expect
If you or a loved one is concerned about possible signs or symptoms of cancer and would like an initial consultation or a second opinion, call us 24/7 at 877-460-4673.
What Is a High White Blood Cell Count?
A white blood cell count measures the number of white blood cells (WBCs) in your blood. White blood cells, also called leukocytes, are part of the immune system and increase when you’re injured, have an infection or get sick. A high WBC — defined as having more than 11,000 white blood cells per microliter of blood in adults — may indicate your body is fighting an infection or disease.
The typical range for leukocytes in your urine is 0–5 white blood cells per high power field (WBC/HPF). This means that between 0 and 5 white blood cells are visible in a urine sample when examined under a high-powered microscope.
A WBC is used to help diagnose or monitor disorders or health conditions indicated by elevated white blood cells, including:
- Autoimmune and inflammatory diseases that cause the immune system to attack healthy tissues and may raise WBC
- Bacterial or viral infections
- Cancers such as leukemia and Hodgkin lymphoma
- Allergic reactions
A WBC may also identify disorders related to having a low white blood cell count, including:
- Diseases of the immune system, such as human immunodeficiency virus (HIV)
- Lymphoma, a cancer of the bone marrow
- Diseases of the liver or spleen
While a WBC may indicate the number of your white blood cells is too high or too low, it isn’t used to confirm a diagnosis. Follow-up tests could include a complete blood count (CBC), blood differential, blood smear and/or bone marrow test.
When to Worry about White Blood Cells in Urine
If you have any of the following symptoms, your doctor may recommend a WBC to determine if you have an infection, inflammation, autoimmune disease or cancer:
- Fever or chills
- Body aches or headache
- Vomiting or nausea
- A wound that is red, has pus or won't heal
- Persistent cough
Symptoms may differ, depending on where in the body the inflammation is and the type of disease you may have. That’s why it’s important to consult a doctor, who can help identify, diagnose and treat the underlying cause of a high white blood cell count.
“The concern increases when WBC elevation is persistent, unexplained and associated with other abnormal blood cells, like anemia or low platelets,” says Dr. Rodriguez. “Also [an elevated WBC] in association to enlarged lymph nodes or spleen, is usually a red flag. In those situations, further evaluation by your doctor is recommendable.”
What is Leukocytosis?
You may hear the term leukocytosis, which is the medical phrase for an elevated white blood cell count. It’s diagnosed when WBC exceeds the normal range for adults — generally 4,000 to 11,000 cells per microliter of blood.
High WBC Blood Test
Elevated WBCs may show up on a urine test, but because they may spill over from urine into the blood, your doctor may order both tests if they suspect you have an elevated white blood cell count, as detailed below.
Blood test (complete blood count): This examines the entire bloodstream and may indicate your body is fighting an illness or infection or experiencing systemic stress.
Urine test: This evaluates local inflammation in the kidneys, bladder or urethra.
When Are White Blood Cells in Urine Cancer
High levels of white blood cells in your urine, also known as pyuria, typically result from infections, including urinary tract infections in the bladder and urethra. But other conditions may also cause elevated levels of leukocytes, including:
- Kidney stones, which are accumulations of minerals and salts in your kidneys that may travel down your urinary tract and become stuck
- Blockages in the urinary system from things such as tumors or kidney stones that may cause bacteria to grow, causing an infection
- Cancers of the kidney, bladder, lung and prostate, which may all raise the levels of leukocytes in your urine
- Certain blood diseases, such as sickle cell anemia, which may cause high leukocyte levels
- Sexually transmitted infections (STIs), fungal infections and parasitic infections
White Blood Cells in Urine: Are They Cancer Symptoms?
Although elevated white blood cells may be caused by nonmalignant conditions, they may also result from certain cancers, including:
- Blood cancers (leukemias and lymphomas) that may cause the bone marrow to produce excessive or abnormal WBCs
- Solid tumors (kidney, bladder, prostate and lung), which may secrete substances that trigger the body to produce higher levels of WBCs
When to Call a Doctor: What to Expect
If you experience any of the following symptoms, you should see a doctor to determine if you have a high WBC and what might be causing it:
- Unexplained, persistent fevers or severe night sweats
- Severe fatigue, weakness, or unexplained weight loss
- Easy bruising or frequent bleeding
- Swollen lymph nodes (neck, armpits or groin)
- Abdominal pain or a feeling of fullness (due to an enlarged spleen)
To determine the underlying cause of elevated white blood cells, doctors utilize use what’s called a WBC differential to see which specific cells are elevated and may order further testing, such as a bone marrow biopsy, if cancer is suspected.
To diagnose what is causing leukocytes in your urine, doctors will typically have you submit a urine sample for analysis. According to the National Kidney Foundation, the three main ways doctors may examine your urine are listed below.
Visual exam: Doctors visually assess the color and clearness of your urine to help narrow down potential causes of leukocytes in your urine.
Dipstick test: Doctors immerse a dipstick covered with strips of chemicals into your urine. The color of the strips may change if high levels of leukocytes are detected.
Microscopic exam: Doctors examine a urine sample under a microscope to help determine your WBC.
Additional testing may be recommended for a fuller picture of your health condition, if your doctor suspects that cancer or a blood disorder is causing leukocytes in your urine.
“Doctors determine the cause of an elevated WBC count by evaluating the whole clinical picture and not only the WBC count,” Dr. Rodgrigez says. “They look into symptoms, medical history, medications and perform a thorough physical examination. Usually the blood work is repeated, and the blood is inspected under a microscope. Most of the causes are reactions to other disorders like infections or inflammation. However, very high WBC count or concerning physical findings usually leads to additional blood tests and, in some cases, even a bone marrow biopsy for examination.”
Treatment involves addressing the underlying cause. If cancer is causing elevated leukocytes to appear in your urine, your doctor may help you determine optimal treatment — such as surgery, chemotherapy and radiation therapy.
If you or a loved one is concerned about possible signs or symptoms of cancer and would like an initial consultation or a second opinion, call us 24/7 at 877-460-4673.