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

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.