Pus Cells in Urine
- Why Do I Have Pus Cells In Urine?
- When to Seek Medical Attention?
- Diagnosis and Treatment
- Who Treats Pus Cells In Urine?
Why Do I Have Pus Cells in Urine?Finding a few pus cells or white blood cells (WBCs) in urine is quite normal. But too many of them may signal a problem somewhere in your urinary tract, the commonest of which is a urinary tract infection (UTI). Your lab will usually report the result as number of cells counted per high power field of the microscope (hpf) or number of WBCs/mL of urine. Usually, 5 to 10 pus cells/hpf or 105 WBCs/mL of urine is considered normal. A high number of pus cells in urine is called pyuria. When a large number of WBCs are present in urine, they may also be detected on a urine dipstick test for leukocyte esterase.
Causes of pus cells in urine:
- Urinary tract infections (UTIs):UTIs are the commonest cause of pus cells in urine. The infection could be anywhere from the kidneys to the urethra, though bladder infection (cystitis) is the commonest. It’s generally an uncomplicated condition that can be promptly resolved with antibiotics.
- People with a UTI: People with a UTI generally also have a large number of bacteria in their urine. In some cases pus cells are found in urine but no bacteria or other infectious organism is found on urine tests. The possible causes of pus cells without bacteria in urine are:
- Uncommon organisms: Some organisms causing infections in the urinary tract do not show up on standard urine culture for indentifying bacteria, for e.g. some sexually-transmitted agents that cause urethral infection. Your doctor may have to order special tests for detecting them. Depending on your medical history and symptoms, some organisms that your doctor may want to test for are N. gonorrheae, Chlamydia, Mycoplasma, Ureaplasma and Trichomonas.
- Tuberculosis: Tuberculosis of the urinary tract can also cause pus cells in urine with negative urine culture. It is a relatively uncommon condition but tests to rule it out may be needed.
- Kidney stones: Stones cause irritation and inflammation in the urinary tract which can lead to pus cells in urine. Kidney stones nearly always also cause the appearance of red blood cells (RBCs) in urine.
- Interstitial cystitis: Interstitial cystitis is a noninfectious condition causing inflammation of the bladder. It is much more common in women than in men. Its symptoms are similar to cystitis but no organism is found on urine culture.
- Prostatitis: Inflammation of the prostate gland in men because of infection or other causes can cause pus cells in urine.
- Cancer: Pus cells in urine are also found in cancers of the kidney or bladder. Cancers often also cause the appearance of blood in urine. The likelihood of cancers increases with age. They are uncommon in people <40 years of age.
- Kidney diseases: Pus cells in urine are found in many noninfectious conditions affecting the kidneys such as glomerulonephritis, interstitial nephritis, lupus nephritis, renal tubular acidosis, renal papillary necrosis, and polycystic kidneys. These diseases produce significant clinical symptoms and many other significant findings on urine test such as protein and blood in urine.
- Renal papillary necrosis: Damage to the kidneys because of diabetes or analgesic abuse can cause pus cells in urine.
- Diseases affecting other organs: At times a serious infection in a organ close to the urinary tract, the appendix for example, can cause pus cells in urine.
- Other causes: Any urinary tract surgery, including prostate surgery, can cause increased pus cells in urine for a long time even in the absence of infection. Stress, dehydration, exercise and certain drugs are also known to cause pus cells in urine.
Diagnosis and TreatmentA urine culture on standard and special media, vaginal or urethral smear examination and some PCR tests will identify any infections in the urinary tract. Some imaging tests such as ultrasound and CT scan are needed if a non-infectious reason is suspected. Treatment will be guided by the diagnosis.
When to Seek Medical Attention?Always talk to your doctor if a significant number of pus cells are present in your urine or your urine dipstick test is positive for leukocyte esterase. You may need to be treated for an infection or investigated further for other possible causes of pyuria.