Knowing what bacteria are causing the infection can help your doctor choose the best treatment. Teaching your child good bathroom habits can help prevent UTIs. They happen when bacteria germs get into the bladder or kidneys. I bought it for my husband and he loves it too The sample may be used for a urinalysis a test that microscopically checks the urine for germs or pus or a urine culture which attempts to grow and identify bacteria in a laboratory. How does my doctor find out my child has a UTI?