Classification of Streptococci

Lancfield Group	Representative	Hemolytic	Typical Infections
A	S. pyogenes	β	Pharyngitis, impetigo, cellulitis, scarlet fever
B	S. agalactiae	β	Neonatal sepsis and meningitis, puerperal infection, urinary tract infection, diabetic ulcer infection, endocarditis
C, G	S. dysgalactiae subsp. equisimilis	β	Cellulitis, bacteremia, endocarditis
D	Enterococci: E. faecalis; E. faecium	Usually nonhemolytic	Urinary tract infection, nosocomial bacteremia, endocarditis
	Nonenterococci: S. bovis	Usually nonhemolytic	Bacteremia, endocarditis
Variable or non goupable	Viridans streptococci: S. sanguis; S. mitis	α	Endocarditis, dental abscess, brain abscess
	Intermedius or milleri group: S. intermedius, S. anginosus, S. constellatus	Variable	Brain abscess, visceral abscess
	Anaerobic streptococci: Peptostreptococcus magnus	Usually nonhemolytic	Sinusitis, pneumonia, empyema, brain abscess, liver abscess