Pus cells in urine: normal range and what a high count means

Pus cells in urine are white blood cells seen under the microscope in a urine sample. Reports may list them as pus cells, WBC or leukocytes, usually as a number per high-power field. A few are expected. A higher count, called pyuria, means there is inflammation somewhere in the urinary tract, most often from an infection.

What the test measures

For the microscope count, about 10 mL of urine is spun in a centrifuge, most of the liquid is poured off, and a drop of the sediment is examined on a slide, at low and then high magnification. A high-power field (HPF) is the area seen at 400 times magnification, and the result is the number of white cells in a typical field. Most of them are neutrophils, which are larger than red cells and have a visible nucleus.

Some laboratories count cells on automated analysers and report white cells per microlitre (µL) of urine instead. The two units are not the same, so check which one your report uses before comparing it with a range.

Normal range

Report	Usual finding in healthy urine
Men, white cells per HPF	Fewer than 2
Women, white cells per HPF	Fewer than 5
Automated count, white cells per µL	Within the laboratory's own range

More than 5 white cells per HPF is consistent with a urinary tract infection (UTI) in someone who has symptoms. For automated counts, UK guidance takes more than 10 white cells per µL (10,000 per mL) to represent inflammation in the urinary tract, including the urethra. Ranges vary by laboratory, method and how the sample was prepared, so the range printed on your own report is the one to read against.

What a high count usually points to

The commonest reason is a UTI, in the bladder or, less often, the kidney. Other causes include:

• Inflammation of the urethra, including sexually transmitted infections such as chlamydia and gonorrhoea.
• Kidney stones, where white cells often come with red cells, crystals and pain.
• Contamination from the skin or vagina during collection. Large squamous epithelial cells in the same sample, more than 5 per HPF, point this way.
• Bacteria living in the urine without causing infection, which is common in older adults, who can show white cells as well.
• Less common causes, including tuberculosis, inflammation within the kidney, recent hard exercise, and medicines such as corticosteroids and cyclophosphamide.

When white cells are present but a urine culture grows no bacteria, doctors call it sterile pyuria. UK guidance suggests considering chlamydia, especially at ages 16 to 24, other vaginal infections, organisms that do not grow on routine culture, including tuberculosis, and kidney causes.

What a doctor typically looks at next:

• Your symptoms, and the rest of the urinalysis, especially Nitrite, Leukocyte Esterase and Bacteria.
• A urine culture, to see whether bacteria grow and which ones.
• A fresh, carefully collected sample if contamination is likely.
• White cell casts, cylinders of cells formed in the kidney's tubules, which point the inflammation towards the kidney itself.
• When a sexually transmitted infection is possible, a separate test. An early-morning sample collected without cleansing detects these infections better than the midstream sample used for a UTI.

What a low count means

A low count, or none at all, is the usual finding. No white cells at all makes a UTI much less likely. A count can also be falsely low if the sample waited too long before it was examined, because white cell counts are not stable in standing urine: in a 2026 study of stored samples, they became unreliable within 4 hours.

What moves it

• Collection. Vaginal secretions and skin contamination add white cells that did not come from the urinary tract. For women, holding the labia apart while collecting may help.
• Time before testing. A sample should be examined within two hours or kept cold, as counts become unreliable with time.
• Exercise and medicines. Hard exercise, corticosteroids and cyclophosphamide are among the listed causes of white cells without infection.
• Infection elsewhere nearby. Infections of the urethra or vagina can add white cells to a urine sample.

Preparing for the test

A urine test needs no fasting, but if blood tests that need fasting are taken at the same visit, follow the instructions for those. Collect a midstream "clean catch": wash your hands, clean the genital area, pass a little urine into the toilet, then collect the middle of the stream. Hand the sample over promptly so it can be examined fresh.

Tell the person taking the sample if you have your period or any discharge, about any urinary symptoms, if you have taken antibiotics recently, and about every medicine you take. Do not stop any medicine before a test unless your doctor tells you to.

How Clare's panel handles it

Clare's panel includes a urinalysis, and in it Urine WBC is measured by the lab: white cells counted under the microscope in the urine sediment. The same sample gives Leukocyte Esterase, the chemical test for the enzyme these cells release, and Epithelial Cells, which help judge whether the sample was contaminated.

Related tests

A white cell count in urine is read with Leukocyte Esterase and Nitrite from the dipstick, and with Bacteria and Epithelial Cells from the same microscope slide. Read together, they help separate infection from contamination. For how the rest of a full panel works, see Comprehensive blood test in Dubai: what to expect.

Why the result means more over time

A raised count with no symptoms can come from contamination during collection, and a carefully collected repeat can settle that. A count that stays raised while cultures grow nothing is the pattern that leads doctors to look further, and it shows up over several tests rather than one. When Clare opens, each urine result will sit in one health account with its date, so a passing finding and a persistent one look different at a glance.

Clare is opening with a waitlist at clare.health.