Clinical Research Directory

Inclusion: * Females between 18 and 55 years of age * Diagnosis of acute uncomplicated pyelonephritis * Can be discharged home on oral antimicrobial treatment * Ability to provide written informed consent in English or Spanish Exclusion: * Took antibiotics in the prior 48 hours * Insulin-dependent diabetes * End-stage liver disease * If the patient reports a penicillin allergy, and is deemed to be high-risk using the penicillin allergy clinical decision rule (PEN-FAST) * Serious allergy (e.g., angioedema, anaphylaxis) to the study medication or a similarly reported allergy to a cephalosporin * Known or identified hydronephrosis, obstruction, or abscess identified by emergency department ultrasound * Presence of a kidney stone * Pregnancy or lactation * Renal dysfunction (defined as creatinine clearance of less than 30 mL/min) * Renal transplantation * Complicated pyelonephritis (defined anatomical or functional abnormality of the urinary tract that predisposes to infection) * Need for additional antimicrobial therapy for a coexisting infection * Human immunodeficiency virus (HIV) infection, with either a recent (in the past 6 months) acquired immune deficiency syndrome-defining condition or a cluster of differentiation-4 (CD-4+) T lymphocyte count \<200/mm\^3