White blood cells, also called leukocytes, are an important part of the immune system. They respond to infections, destroy invaders, and in general help make sure any displeasure our bodies suffer is eliminated. Like all cells, leukocytes eventually die and are filtered out of the body. When you urinate, you are expelling a small number of dead leukocytes.The key word here is “small.”
Under certain conditions, leukocytes are expelled in larger quantities—sometimes enough to be visible as cloudy urine. This never happens without an underlying cause, so it’s important to pay attention to the signals your body sends you.
Leukocyte levels are determined by a urinalysis, where you pee in a cup and the result is analyzed. There are a few different forms of testing that can be done on your sample. Microscopic examination, visual inspection, and chemical analysis with a dip stick to test for certain reactions are all used to identify various contents of the urine.
The results of the test, combined with any other symptoms you are experiencing, will assist the doctor in forming their full diagnoses. A number of different conditions can result in excess leukocyte levels in urine, each with differing characteristics and causes.
Kidney Infection
When the kidney becomes infected by bacteria, a condition called pyelonephritis can occur. This results in white blood cells and bacteria ending up in the urine along with flank pain, nausea, vomiting, fever, and malaise. Women, those with compromised immune systems, or those who use catheters are at a higher risk of kidney infection. A urinalysis would show leukocytes, bacteria, and nitrites (the result of bacteria processing nitrates), along with possibly hemoglobin, depending on severity.
Urinary Blockage
When an obstruction occurs along the urinary tract, whether from a foreign object, trauma, or something like a kidney or bladder stone, the result is a urinary blockage. The obstruction impedes the flow of urine and agitates the surrounding tissue. White blood cells will respond to the irritation and subsequently end up in the urine that manages to get passed, along with blood.
Symptoms of a urinary blockage include difficulty urinating and intense flank pain. Some causes of urinary blockages affect men or women unevenly, but overall they experience comparable levels. A urinalysis during a urinary blockage is likely to show leukocytes and hemoglobin. Since there is not a bacterial infection (though one can develop from a blockage), nitrites are not normally found.
Pregnancy
Pregnancy causes a plethora of changes in the body. One of these changes is the potential proliferation of bacteria in the urinary tract, called asymptomatic bacteriuria, which occurs in around two percent to 10% of pregnancies. As the name implies, asymptomatic bacteriuria has no symptoms. However, a urinalysis would reveal nitrites, bacteria, and leukocytes. This is the main reason pregnant women regularly have their urine tested, since the condition can’t be detected otherwise.
During pregnancy, the rate of vaginal secretions increases to keep the area clean. These secretions can become mixed with urine and be another source of leukocytes.
Urinary Tract Infection (UTI)
When bacteria enter the urethra, they can reach the bladder and result in an infection. Since their urethras are shorter, women are more prone to UTIs than men. Symptoms of a UTI include an increased need to urinate, bladder spasms, and pain above the groin area. A urinalysis would reveal leukocytes, nitrites, and bacteria.
UTIs can come from many sources. Wearing dirty underwear, sexual intercourse, improper wiping, and more can all increase the risk of bacteria entering the urethra. Additionally, some other urinary conditions can lead to a UTI. For instance, stagnant urine retained by an obstruction or the bacteria proliferation from pregnancy can sometimes result in a UTI if not addressed quickly enough.
Interstitial Cystitis
This is a chronic condition also known as Painful Bladder Syndrome. The exact cause is unknown, but is believed to be related to the composition of the bladder’s lining or the signals it sends and receives from the brain. In cases of interstitial cystitis, the bladder becomes inflamed and causes pelvic pain between the anus and scrotum or vagina, frequent urination in small amounts, and pain or discomfort that increases as the bladder fills.
More women experience the condition than men and the symptoms tend to vary in intensity over time, in general resembling those of a UTI. However, a urinalysis would only show leukocytes that have responded to the inflammation and no traces of bacteria.
Treating Leukocytes in Urine
Reducing leukocyte levels in your urine mainly involves addressing whatever is getting the white blood cells busy in the first place. For pyelonephritis, UTIs, and pregnancy, antibiotics and being sure to stay hydrated are the main options. Urinary blockages can be relieved by passing the offending object, having kidney or bladder stones broken up by sound waves and then passing them, or surgery. Interstitial cystitis is more complicated, but usually involves either surgery or medication to help protect the bladder’s mucous lining.
By paying attention to what you feel, see, and smell coming from your body, you can stay on top of any urinary problems and get them treated before any major issues develop.
Related Reading:
Sources for Today’s Article:
“Interstitial Cystitis,” Mayo Clinic web site, January 2, 2014; http://www.mayoclinic.org/diseases-conditions/interstitial-cystitis/basics/symptoms/con-20022439.
Khara, K., “Leukocytes in Urine,” Buzzle web site, last updated May 28, 2013; http://www.buzzle.com/articles/leukocytes-in-urine.html, last accessed September 22, 2015.
“Cloudy urine: Causes, symptoms, and treatments,” Belmarrahealth.com; http://www.belmarrahealth.com/cloudy-urine-causes-symptoms-and-treatments/, last accessed July 15, 2016.
Perkins, S., “Causes of White Blood Cells in Urine,” Livestrong.com, April 13, 2015; http://www.livestrong.com/article/81433-causes-white-blood-cells-urine/.