The test is due to her having symptoms, it is one of those things that isn't done as routine as it would be pointless. My vets only do annual urine tests on older cats and that is only cos kidney issues and diabetes can show in them.
HArna, it depends on the cat, I have had 3 cats with UTI's and all have been different - only one has been the 'typical' trying to wee and only doing small amounts and having blood in it, Pebbles only indication was the strong smell, and Tom sprayed (while his was stress related, he did have crystals). Some cats have it once and then never ever have an issue with it - it never returned in either of the girls, although they did both only live another 18 months. Tom's was stress, and has never returned after leaving here