title: Are first-generation cephalosporins obsolete? A retrospective, non-inferiority, cohort study comparing empirical therapy with cefazolin versus ceftriaxone for acute pyelonephritis in hospitalized patients.
abstract: Literature is lacking regarding the utilization of first-generation cephalosporins for the treatment of acute pyelonephritis. The aim of this study was to determine whether cefazolin is non-inferior to ceftriaxone for the empirical treatment of acute pyelonephritis in hospitalized patients. The primary outcome included a composite of symptomatic resolution plus either defervescence at 72 h or normalization of serum white blood cell count at 72 h (non-inferiority margin 15%). Secondary outcomes included length of stay and 30 day readmission. A subgroup analysis of the composite outcome was also conducted for imaging-confirmed pyelonephritis.
  
  
  
  This was a retrospective, non-inferiority, multicentre, cohort study comparing cefazolin versus ceftriaxone for the empirical treatment of acute pyelonephritis in hospitalized patients.
  
  
  
  Overall, 184 patients received one of the two treatments between July 2009 and March 2015. The composite outcome was achieved in 80/92 (87.0%) in the cefazolin group versus 79/92 (85.9%) in the ceftriaxone group (absolute difference 1.1%, 95% CI -11.1% to 8.9%, P = 0.83), meeting the pre-defined criteria for non-inferiority. The composite outcome for patients with imaging-confirmed pyelonephritis was achieved in 46/56 (82.1%) versus 42/50 (84.0%) for the cefazolin group and the ceftriaxone group, respectively (absolute difference 1.9%, 95% CI -12.8% to 16.5%, P = 0.80). Additionally, there were no statistically significant differences in length of stay or 30 day readmission for cystitis or pyelonephritis.
  
  
  
  Cefazolin was non-inferior to ceftriaxone with regard to clinical response for the treatment of hospitalized patients with acute pyelonephritis in this study. No difference was observed for length of stay or 30 day readmission.
authors.affiliation: Department of Pharmacy, Baptist Memorial Hospital Memphis, 6019 Walnut Grove Rd, Memphis, TN 38120, USA athena.hobbs@bmhcc.org.
authors.forename: Athena L V
authors.initials: AL
authors.lastname: Hobbs
authors.affiliation: Cardinal Health, Innovative Delivery Solutions, 1330 Enclave Pkwy, Houston, TX 77077, USA.
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Shea
authors.affiliation: Department of Pharmacy, Seton Healthcare Family, 601 E 15th St, Austin, TX 78701, USA.
authors.forename: Mitchell J
authors.initials: MJ
authors.lastname: Daley
authors.affiliation: Department of Medicine, The University of Texas at Austin Dell Medical School, 601 E 15th St, Austin, TX 78701, USA.
authors.forename: R Gordon
authors.initials: RG
authors.lastname: Huth
authors.affiliation: Department of Pharmacy, Seton Healthcare Family, 601 E 15th St, Austin, TX 78701, USA.
authors.forename: Theresa C
authors.initials: TC
authors.lastname: Jaso
authors.affiliation: Austin ID Consultants, 1301 W 38th St, Austin, TX 78705, USA.
authors.forename: Jack
authors.initials: J
authors.lastname: Bissett
authors.affiliation: Department of Medicine, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Vagish
authors.initials: V
authors.lastname: Hemmige
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002437:Cefazolin / Q000627:therapeutic use*; D002443:Ceftriaxone / Q000627:therapeutic use*; D002511:Cephalosporins / Q000627:therapeutic use*; D015331:Cohort Studies; D036262:Empirical Research; D004926:Escherichia coli / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000652:urine; D005260:Female; D006760:Hospitalization; D006801:Humans; D007902:Length of Stay; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission; D011704:Pyelonephritis / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000382:microbiology; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D002443:Ceftriaxone; D002437:Cefazolin