Streptococci

Please note: This is for information only.

Refer to local guidelines for treatment recommendations


  • Gram-positive cocci, in pairs or chains.

Main pathogens are:

  • Group A streptococcus (S. pyogenes)
  • Group B streptococcus (S. agalactiae)
  • S. pneumoniae (pneumococcus)
  • Viridans streptococci (endocarditis)

Main clinical manifestations:

  • Group A strep.
  • Tonsillitis
  • Wound infection
  • Cellulitis
  • Necrotising fasciitis
  • Puerperal sepsis (now rare)
  • Septicaemia
  • Recent increase in incidence in intravenous drug users.
  • Group B strep.
  • UTI
  • neonatal sepsis
  • endocarditis
  • Increase risk in diabetics.
  • S. pneumoniae
  • pneumonia
  • meningitis
  • bone/joint infections
  • Increased risk in asplenia/myeloma.

Usually sensitive to:

  • Penicillin
  • NOTE: increase in acquired resistance to penicillin (more common in other European countries than in UK).
  • Cephalosporins
  • Macrolides (erythromycin, clarithromycin) (acquired resistance common)
  • Glycopeptides (vancomycin, teicoplanin)

Usually resistant to:

  • Ciprofloxacin
  • Gentamicin (unless in combination with penicillin / glycopeptides)
  • Trimethoprim