Piuria: What is it? Causes, Symptoms, Diagnosis, Treatment and Overview

It is a urinary condition characterized by many white blood cells in the urine.

Doctors define a high number as at least ten white blood cells per cubic millimeter (mm3) of centrifuged urine. Pyuria can make your urine look cloudy or like it has pus in it.

Pyuria often occurs in a urinary tract infection (UTI). It can be a sign of complicated UTI or sepsis in rare cases.

A sterile pyuria is a form of pyuria that occurs without a detected presence of bacteria. In these cases, it may be related to undetected bacteria, a virus or other type of germ, or some other underlying medical condition.


A urinary infection usually causes pyuria.

Pyuria can occur as a result of many different conditions. It is most often caused by a UTI, an infection in any area of ​​the urinary system, including the kidneys, ureters, urethra, or bladder.

Sterile pyuria is most often caused by sexually transmitted infections (STIs), such as gonorrhea or viral infections.


Other causes of sterile pyuria include:

  • Interstitial cystitis.
  • Bacteremia with sepsis.
  • Tuberculosis.
  • Urinary tract stones.
  • Kidney disease
  • Prostatitis.
  • Pneumonia.
  • Autoimmune diseases, such as SLE or Kawasaki disease.
  • Parasites
  • Tumors in the urinary tract.
  • Polycystic (kidney disease).

Pyuria can also be a reaction to taking certain types of medications, including:

  • Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and aspirin.
  • Diuretics
  • Penicillin antibiotics.
  • Proton pump inhibitors, such as omeprazole.


Pyuria can cause cloudy urine and urine with pus that other symptoms may not accompany. The change in color or texture is due to an increase in white blood cells.

If there is a urinary tract infection, symptoms can also include:

  • Frequent urges to urinate
  • A burning sensation when urinating.
  • Blood in the urine.
  • Smelly urine.
  • Pelvic pain.
  • Fever.

Other symptoms that can occur if another underlying condition causes pyuria:

  • Fever.
  • Abdominal pain.
  • Abnormal discharge.
  • Difficulty breathing.
  • Nausea or vomiting

Untreated UTIs can cause serious complications, including sepsis.


A doctor will do a urinalysis to diagnose pyuria. This involves taking a urine sample, which is then analyzed based on its appearance, concentration, and content.

Cloudy urine with an abnormal white blood cell count may indicate pyuria.

Urinalysis may also highlight other abnormalities. For example, the presence of nitrite or leukocyte esterase can indicate a UTI, while elevated levels of protein can indicate kidney disease.


Pyuria can be treated with antibiotics.

Treatment for pyuria depends on the underlying cause. Typically, a UTI causes pyuria, and treatment will involve a short course of antibiotics, such as oral trimethoprim-sulfamethoxazole or nitrofurantoin.

Antibiotics can also treat bacterial STIs and tuberculosis. If you do not improve after taking an entire course of antibiotics, there may be a more serious underlying condition.

In some cases, stopping medications that trigger increased white blood cells in the urine can treat pyuria. However, it is essential to consult a doctor before stopping or changing any medication.

During pregnancy

Pyuria and UTIs often occur during pregnancy. This is due to anatomical and hormonal changes during pregnancy that allows bacteria to enter the urinary tract and grow.

Anyone with pyuria during pregnancy should speak with a doctor to determine the underlying cause. An infection or asymptomatic presence of bacteria in the urine during pregnancy can be harmful and cause complications for the baby.


Most cases of pyuria do not pose a severe health risk, but anyone with pyuria should speak with a doctor to help determine the underlying cause.

UTIs are a common cause of pyuria that doctors can treat with a short course of antibiotics. If antibiotics cannot treat symptoms, a person should seek additional medical attention.

If a person experiences pyuria during pregnancy, they should talk to their doctor about the best way to minimize the risk of complications.