Pyuria is a urinary condition related to white blood cells that is diagnosed with a urine test. It can have many causes, and the treatment depends on the cause.

Your doctor will diagnose pyuria if you have at least 10 white blood cells in each cubic millimeter of urine. This often indicates infection.

In sterile pyuria, however, persistent white cell counts appear during testing without bacterial infection.

Learn more about pyuria and how you can treat and prevent it.

A urinary tract infection (UTI) is the most common cause of pyuria.

Other causes of pyuria may include:

The long-term use of the following drugs can also cause pyuria:

  • antibiotics with penicillin
  • aspirin
  • diuretics
  • olsalazine
  • nitrofurantoin
  • non-steroidal noninflammatory drugs, such as ibuprofen (Advil, Motrin)
  • proton pump inhibitors

Symptoms of a UTI may include:

  • frequent urination
  • blood in the urine
  • cloudy urine
  • burning sensations during urination

Pyuria not caused by a UTI can share similar symptoms. You may notice:

  • bladder pain
  • nausea or vomiting, which may be a sign of kidney problems
  • cloudy urine
  • discharge
  • abdominal pain
  • fever and chills

Some cases of pyuria don’t cause symptoms. It’s important to have an annual urine test to detect possible issues.

Women are at a greater risk for pyuria than men. Pyuria is also more common in older adults. Sterile pyuria is more common in older women. This is associated with a natural drop in estrogenization levels. Menopause is another factor that can increase risk for pyuria in women because of the higher risk for UTIs in menopause.

Being sexually active may also increase your risk for getting pyuria. That’s because certain STDs, such as chlamydia, can cause pyuria. Sexual activity may also increase your risk for UTI.

Your doctor will diagnose pyuria with a urine sample called a urinalysis. A lab technician will look for the presence of bacteria, blood, and white blood cells. While white blood cells are present in all pyuria cases, not all samples will show bacteria or blood. The amount of these elements will help your doctor determine the precise cause of pyuria.

A UTI is diagnosed if there are nitrites or leukocytes present in the urine. If these elements aren’t found during a urinalysis, then your doctor will likely look for other signs of pyuria, such as white blood cell counts.

What you should know about leukocytes in urine »

Treatment for pyuria depends on its cause. A UTI is typically treated with a round of antibiotics. These are taken orally for up to two weeks. Antifungal medications may be used to treat pyuria caused by a fungus.

Pyuria that doesn’t respond to antibiotics may have another underlying cause. For example, Kawasaki disease is treated with immunoglobulins.

Frequent cases of pyuria related to medications may clear up by stopping certain prescription drugs. Your doctor may offer another brand or type in its place.

Left untreated, pyuria can lead to further health complications. Since most cases are caused by some form of an infection, this can spread throughout the body. Untreated infections can lead to blood poisoning and organ failure. Permanent kidney damage is a concern with untreated UTIs. Severe cases of pyuria, left untreated, could be fatal.

Sometimes getting an incorrect diagnosis can also complicate treatment. In some cases, treating pyuria with an antibiotic may make the condition worse. This is perhaps because many symptoms of pyuria are actually attributed to inflammation and not bacterial infection.

If you’re pregnant, a routine uranalysis may show pyuria. While this can be alarming, pyuria is actually common during pregnancy. It can happen because of excess vaginal discharge. If your test reveals pyuria, your doctor will need to determine the cause to recommend the best course of treatment. While vaginal discharge may contaminate urinalysis results, it’s important to make sure you don’t have a UTI or another type of infection.

Usually pyuria isn’t a cause for concern in pregnant women. If misdiagnosed or left untreated, though, it could put you and your baby at risk for further health complications. Severe pyuria associated with an untreated UTI may lead to premature birth or a low birth weight in full-term babies.

Read more: UTI during pregnancy »

The outlook for pyuria largely depends on the cause as well as how early it’s treated. For most people, it can clear up with prompt treatment. If you have frequent UTIs or other chronic or ongoing conditions, you might get recurring cases of pyuria.

The best approach is to be aware of your symptoms and see a doctor if something doesn’t look or feel right. It’s also important for older people who may be more prone to the onset and subsequent complications of pyuria to get prompt treatment. Your doctor may refer you to a urologist for a more accurate diagnosis and treatment.