A urinalysis is a laboratory test done to detect problems with the body that can appear in your urine.
Several illnesses and disorders affect how the body removes waste and toxins. The system that takes care of that is broadly called the excretory system, and includes lungs, kidneys, urinary tract, skin, and bladder. Problems with any of these parts of the body can affect the appearance, concentration, and content of urine
Usually the test involve using a reagent impregnated strips that react in the presence of urine constituents to produce a colored end product.