There are a few incorrect assumptions here that are common when people are learning about TCM. First there is most often a great difference in the physical organs in western terms and their corresponding systems in TCM terms. So a bacterial infection in the kidneys (i.e. pyelonephritis) is not necessarily related at all to the “kidney” system in Chinese Medicine (which long story short is more closely related to our hormones, adrenals, thyroid and other miscellaneous functions, than it is to any of the physical functions of the kidneys in western terms).
To start with that, I would suggest reading:
Bacterial infections are often, but not always, damp heat which may arise from a multitude of factors. As a practitioner your job is to figure out the deeper causal patterns, not mapping a issue/symptom to a diagnosis that seems to fit - see “Treating the cause vs. the symptoms” for more on that.
To get you in the ballpark our UTI Treatment Section has most of the common formulas that would potentially be used (chosen by arriving at the correct underlying TCM diagnosis) - Ba Zheng Wan and/or San Jin Wan being quite commonly used (they generally outperform antibiotics, but can be used with them as well).