title: Azithromycin versus doxycycline for the treatment of genital chlamydia infection: a meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  There has been recent debate questioning the efficacy of azithromycin for the treatment of urogenital chlamydia infection. We conducted a meta-analysis to compare the efficacy of 1 g azithromycin with 100 mg doxycycline twice daily (7 days) for the treatment of urogenital chlamydia infection.
  
  
  METHODS
  Medline, PubMed, Embase, Cochrane Controlled Trials Register, Cochrane reviews, and Cumulative Index to Nursing and Allied Health Literature were searched until 31 December 2013. Randomized controlled trials comparing azithromycin with doxycycline for the treatment of genital chlamydia with evaluation of microbiological cure within 3 months of treatment were included. Sex, diagnostic test, follow-up time, attrition, patient symptomatic status, and microbiological cure were extracted. The primary outcome was the difference in efficacy at final follow-up. Study bias was quantitatively and qualitatively summarized.
  
  
  RESULTS
  Twenty-three studies were included evaluating 1147 and 912 patients for azithromycin and doxycycline, respectively. We found a pooled efficacy difference in favor of doxycycline of 1.5% (95% confidence interval [CI], -.1% to 3.1%; I(2) = 1.9%; P = .435; random effects) to 2.6% (95% CI, .5%-4.7%; fixed effects). Subgroup analyses showed that the fixed effects pooled efficacy difference for symptomatic men was 7.4% (95% CI, 2.0%-12.9%), and the random effects was 5.5% (95% CI, -1.4% to 12.4%).
  
  
  CONCLUSIONS
  There may be a small increased efficacy of up to 3% for doxycycline compared with azithromycin for the treatment of urogenital chlamydia and about 7% increased efficacy for doxycycline for the treatment of symptomatic urethral infection in men. However, the quality of the evidence varies considerably, with few double-blind placebo-controlled trials conducted. Given increasing concern about potential azithromycin failure, further well-designed and statistically powered double-blind, placebo-controlled trials are needed.
authors.affiliation: Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne.
authors.forename: F Y S
authors.initials: FY
authors.lastname: Kong
authors.affiliation: Murdoch Children's Research Institute, Parkville.
authors.forename: S N
authors.initials: SN
authors.lastname: Tabrizi
authors.affiliation: Kirby Institute, University of New South Wales, Sydney.
authors.forename: M
authors.initials: M
authors.lastname: Law
authors.affiliation: Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne Murdoch Children's Research Institute, Parkville.
authors.forename: L A
authors.initials: LA
authors.lastname: Vodstrcil
authors.affiliation: Sexual Health Unit, Melbourne School of Population and Global Health Melbourne, University of Melbourne Melbourne Sexual Health Centre, Melbourne, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Chen
authors.affiliation: Melbourne Sexual Health Centre, Melbourne, Australia.
authors.forename: C K
authors.initials: CK
authors.lastname: Fairley
authors.affiliation: Kirby Institute, University of New South Wales, Sydney.
authors.forename: R
authors.initials: R
authors.lastname: Guy
authors.affiliation: Sexual Health Unit, Melbourne School of Population and Global Health Melbourne, University of Melbourne Melbourne Sexual Health Centre, Melbourne, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Bradshaw
authors.affiliation: Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne.
authors.forename: J S
authors.initials: JS
authors.lastname: Hocking
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017963:Azithromycin / Q000627:therapeutic use*; D002690:Chlamydia Infections / Q000188:drug therapy*; D004318:Doxycycline / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D060737:Reproductive Tract Infections / Q000188:drug therapy*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D017963:Azithromycin; D004318:Doxycycline
keywords: azithromycin; doxycycline; genital chlamydia; meta-analysis; treatment efficacy