Mycoplasma pneumoniae is a common respiratory pathogen, especially in children, responsible for community-acquired pneumonia. Although, in most cases, infections caused by this bacterium follow a benign self-limited clinical course, cases of severe respiratory infections have been reported. We present two pediatric cases of necrotizing pneumonia due to Mycoplasma pneumoniae. Both patients initially presented with low-grade fever, cough and mild respiratory symptoms, however, imaging techniques showed necrotizing pneumonia. Initially, a typical bacterial pneumonia was suspected, so antibiotic empiric regimen did not included macrolides. When clinical evolution was not adequate, antibiotic treatment was modified in order to provide coverage to unusual pathogens. Both patients finally recovered once Mycoplasma was suspected, and oral macrolides were added to their treatment. Although M. pneumoniae is a rare cause of necrotizing pneumonia, it must be considered, when usual antibiotic empiric therapy is not being successful. Before thinking of uncommon germs, we must remember that: 'The unusual presentation of a common disease is generally more likely than the usual presentation of an uncommon disease'.
Keywords: Mycoplasma pneumoniae; children; community-acquierd pneumonia; necrotizing pneumonia.