How is the condition diagnosed?

After doing a physical examination on the child and listening to the history of symptoms, the healthcare provider will order tests on the child's urine. Different methods are used to collect the urine, depending on the child's age. Urine must be collected in as sterile, or bacteria-free, a manner as possible.

Children who are toilet-trained are asked to urinate into a sterile container after cleaning themselves. In younger children, it may be necessary to pass a small tube, or catheter, into the urethra to get a sterile urine sample. Sometimes, a needle is inserted directly into the bladder through the skin of the lower abdomen to get a sample. On occasion, a collection bag is used in children who are not yet toilet-trained. The collection bag is placed over the genital area until the child urinates.

A urinalysis is first done on the urine. This test checks for abnormal blood cells and for bacteria in the urine. After a urinalysis, a urine culture may also be done. This test can identify the specific type of bacteria causing the infection. The urine is left on a special dish to allow the bacteria to multiply. The larger number of bacteria makes it easier to identify them. Different antibiotics can be used on the bacteria to figure out which one works best. This helps the healthcare provider choose the best medication to treat that particular infection.