Patients will be identified based on clinic visits or hospital admission. All patients will be counseled on standard treatment options—extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS). The discussion regarding treatment options and subsequent care will not deviate from routine care. Patients consenting for percutaneous nephrolithotomy (PCNL) will be considered for enrollment into the study and will be enrolled to have data collected prospectively. Patients will be consented prior to prescription of antibiotics and to the surgery for collection of demographic, disease, perioperative, and postoperative data. Abdominal pelvic computed tomography (CT), if not already obtained, will be used to delineate pre-operative stone size and for preoperative planning. If the patient does not consent to the study, the use of antibiotics will be based on routine clinical practice of the treating urologist. Both prophylaxis with preoperative antibiotics and no prophylaxis (i.e. periprocedural only) are considered standard of care.