Pneumococcal surface protein A family types of Streptococcus pneumoniae from community-acquired pneumonia patients in Japan.

We assessed pneumococcal surface protein A (PspA) family types of 141 isolates of Streptococcus pneumoniae from community-acquired pneumonia patients in Japan. Families 1 and 2 were expressed in 78 (55.3%) and 58 (41.1%) isolates, respectively. Five isolates were not typed either as family 1 or 2. PspA family types were not associated with age, sex, or pneumonia severity. Penicillin-resistant S. pneumoniae was more likely to belong to family 2 whereas organisms highly resistant to erythromycin and positive for ermB were more prevalent in family 1. The association of PspA type with antimicrobial resistance was possibly affected by prevalent serotypes or resistance clones. It would therefore be necessary to include both family 1 and 2 proteins in a PspA-containing vaccine to cover the major PspA families and to reduce antimicrobial resistance.