They check for everything...
Urinalysis in Dogs - Page 1 A urinalysis helps to evaluate the function of the kidneys and the quality of the urine produced. A urinalysis usually consists of three parts; examining the physical sample, a dipstick analysis to evaluate the presence of certain substances and microscopic examination of the sediment. A urinalysis can evaluate for pyuria (white blood cells in the urine), hematuria (blood in the urine), crystalluria (crystals in the urine), the presence of abnormal amounts of glucose, ketones and protein, and urine concentration.
With recurring UTIs you may want to ask your vet about running a Bile Acid Test, to test liver function, and specific bloodwork to check her kidney function.