A sample of fresh urine taken at the clinic is dropped onto a plate for immediate analysis under a microscope.

White blood cells and epithelial cells are counted as markers of an infection.

When infection occurs in the urinary tract, the immune system tries to remove infected cells by shedding the cells in the bladder lining (the epithelium) to be excreted during urination – these are known as epithelial cells.

A high white blood cell count usually indicates that the body is fighting an infection. White blood cells rush in to help destroy the harmful substance and prevent the infection developing further as part of the immune system response to pathogenic bacteria.

The need for immediate analysis of a urine sample is because white blood cells degrade very quickly. Studies have shown this occurs in as little as four hours unless collected in an appropriate sample bottle containing a boric acid preservative.  A sample sent for analysis at the laboratory may not identify sufficient or any white blood cells if there is a delay in the delivery and analysis within a four hour period or urine collection does not involve a sample container that utilises boric acid to help preservation.