Penicillin resistant pneumococcus and risk of treatment failure in pneumonia
- Maria Regina Alves Cardoso (rcardoso{at}usp.br)
- Fernando Ferrero (ferrero{at}intramed.net.ar)
- Eitan N Berezin (eberezi{at}zipmail.com.br)
- Jesus Feris-Iglesia (infectologia{at}codetel.net.do)
Abstract
Objective: To determine whether the presence of in-vitro penicillin resistant Streptococcus pneumoniae increases the risk of clinical failure in children hospitalized with severe pneumonia and treated with penicillin/ampicillin.
Design: Multicentre, prospective, observational study.
Setting: 12 tertiary-care centres in three countries in Latin America.
Patients: 240 children aged 3–59 months, hospitalized with severe pneumonia and known in-vitro susceptibility of S. pneumoniae.
Intervention: Patients were treated with IV penicillin/ampicillin, after collection of blood and, when possible, pleural fluid for culture. Minimal Inhibitory Concentration (MIC) test was used to determine penicillin susceptibility of the pneumococcal strains isolated. Children were continuously monitored until discharge.
Main outcome measures: The primary outcome was treatment failure (clinical criteria).
Results: Overall treatment failure was 21%. After allowing for different potential confounders, there was no evidence of association between treatment failure and in-vitro resistance of S. pneumoniae to penicillin according to the CLSI/NCCLS interpretative standards (adjRR=1.03; 95%CI: 0.49 – 1.90 for resistant S. pneumoniae).
Conclusions: IV penicillin/ampicillin remains the drug of choice for treating penicillin resistant pneumococcal pneumonia in areas where the MIC does not exceed 2μg/mL.
