Group 2 patients will be randomized to either 7 days or 48 hours of oral antibiotics prior to the PCNL with the final day of prophylactic course being 1 day prior to surgery. Antibiotic choice will be determined by the culture sensitivity profile, with nitrofurantoin monohydrate/macrocrystalline 100 mg twice daily being the preferred agent if shown to be effective against the uropathogen(s). If patient has previous allergies to Macrobid and/or sensitivity profile indicates ineffectiveness of Macrobid, then one antibiotic will be provided in the following order: nitrofurantoin > sulfamethoxazole-trimethoprim > doxycycline> ciprofloxacin > keflex > cefpodoxime.