Author: Alicia Oberle, MD Educational Pearls:   Recent study has shown risk factors for return included patients at high risk for resistance (nursing home, obstructive uropathy), patient where diagnogsis of pyelonephritis was missed, but the biggest risk factor was the existence of bug-drug mismatches. Cephalexin (Keflex) was associated with highest rate of return, while nitrofurantoin (Macrobid) was associated with lowest return rate. Recommendation is to continue to detect between pyelonephritis and cystitis, broaden coverage for patients with complications, and utilize your facilities antibiogram.   References: Jorgensen S, et al. ( 2018). Risk factors for early return visits to the emergency department in patients with urinary tract infection. American Journal of Emergency Medicine. 36(1):12-17