[Community-acquired pneumonia in children: etiology and treatment].

Due to their very different etiological agents, community-acquired pneumoniae in children frequently require empiric antibiotic therapy in emergency. Streptococcus pneumoniae represents between 15 to 30% of the etiologies and has unspecific diagnostic procedures; as a matter of fact radiological lobar consolidation is seen in less than half of cases, and laboratory data, except for high procalcitonin level, are poorly reliable. Pneumonia due to Mycoplasma pneumoniae is frequent after 2 years of age, reaching 40 to 60% of causes in ambulatory teenagers; it must be treated with macrolides as sequellae are possible. The exact number of viral pneumonia is difficult to establish because of the lack of reliable diagnostic methods. If bacterial superinfections are probably overestimated during acute phase, viral infections may lead to bacterial pneumonia 2 to 4 weeks after the initial episode. Empiric antibiotic treatment must take into account pneumococci and their penicillin-resistant strains. Amoxicillin is the antibiotic of choice, having a higher efficacy on resistant pneumococci than oral cephalosporins. In case of clinical failure of amoxicillin, mycoplasma infection must be considered and patient must receive macrolides. Future epidemiology will be affected by anti-pneumococcal immunisation but difficulties in diagnosis and empiric antibiotic treatment will probably remain. Studies in immunised children are needed to evaluate the importance of pneumococcal infections due to serotypes not included in the vaccine.