How Is a Urinalysis Done?

The kidneys make urine as they filter wastes from the bloodstream while leaving substances in the blood that the body needs, like protein and glucose. So when a child's urine contains protein and glucose or has other irregularities, it's usually a sign that there's some sort of infection or other health problem.

In most cases, urine is collected in a clean container, then a plastic stick that has patches of chemicals on it (the dipstick) is placed in the urine. The patches change color to indicate certain things, like the presence of white blood cells or glucose.

The doctor or laboratory technologist also usually examines the urine under a microscope to check for other substances that indicate different conditions.

If a urinalysis shows white blood cells and bacteria - which may mean that there's an infection in the kidneys or the bladder - the doctor may decide to send the urine to a lab for a urine culture to identify the bacteria.