Pulmonary Disease Associated With Nonencapsulated Streptococcus pneumoniae.

We discuss 3 patients presenting with pneumonia associated with nonencapsulated Streptococcus pneumoniae (NESp), an emerging pathogen commonly causing upper respiratory infections. Clinical isolates obtained from these patients were characterized to evaluate their respective antibiotic resistance and virulence mechanisms. We demonstrate that NESp resistant to classical drug treatments are isolated during pneumonia.