Evolution of acute infection with atypical bacteria in a prospective cohort of children with community-acquired pneumonia receiving amoxicillin

J Antimicrob Chemother. 2017 Aug 1;72(8):2378-2384. doi: 10.1093/jac/dkx126.


Background: Atypical bacteria are treatable causative agents of community-acquired pneumonia (CAP). However, there is no conclusive evidence that a child with CAP should receive empirical treatment against such agents.

Objectives: We assessed the possibility of association between clinical failure and acute infection by these bacteria among children with CAP treated with amoxicillin.

Patients and methods: Patients aged 2-59 months with non-severe CAP received amoxicillin during prospective follow-up. Acute and convalescent blood samples were collected. Probable acute infection by Mycoplasma pneumoniae (specific IgM antibodies), by Chlamydia pneumoniae or Chlamydia trachomatis (specific IgM antibodies and/or IgG/IgA titre change) was investigated. Outcomes were assessed during follow-up at 2, 5 and 14-28 days. Treatment failure included development of danger signs, persistent fever, tachypnoea or death. ClinicalTrials.gov: NCT01200706.

Results: Of 787 children, 86 (10.9%; 95% CI = 8.9%-13.3%) had acute M. pneumoniae infection. C. pneumoniae acute infection was found in 79 of 733 (10.8%; 95% CI = 8.7%-13.2%) and C. trachomatis was found in 3 of 28 (10.7%; 95% CI = 2.8%-26.5%) <6 months old. Among patients with or without treatment failure at 2 days, acute M. pneumoniae infection (11.7% versus 10.7%; P = 0.7), acute C. pneumoniae infection (8.5% versus 11.3%; P = 0.3) and acute C. trachomatis infection (16.7% versus 9.1%; P = 0.5) were found. No significant differences were found with regard to treatment failure at the 5 day evaluation. Overall, amoxicillin was substituted in 3.5% versus 2.7% among patients with or without acute infection by one of these bacteria ( P = 0.6).

Conclusions: The overall substitution rate of amoxicillin was very low. It is not necessary to give an empirical non-β-lactam antibiotic as a first-line option to treat every child between 2 and 59 months old with non-severe CAP.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoxicillin / administration & dosage*
  • Anti-Bacterial Agents / administration & dosage*
  • Child, Preschool
  • Chlamydia / isolation & purification*
  • Community-Acquired Infections / drug therapy*
  • Community-Acquired Infections / microbiology
  • Female
  • Humans
  • Infant
  • Male
  • Mycoplasma / isolation & purification*
  • Pneumonia, Bacterial / drug therapy*
  • Pneumonia, Bacterial / microbiology
  • Prospective Studies


  • Anti-Bacterial Agents
  • Amoxicillin

Associated data

  • ClinicalTrials.gov/NCT01200706