Other Streptococcus Species and Enterococcus

Abstract

The genus Streptococcus and Enterococcus are a group consisting of a various Gram-positive cocci that are usually arranged in pairs or chairs. Most species are facultative anaerobes, and some grow only in an atmosphere enriched with carbon dioxide. Some species of the genus Streptococcus are important human pathogens, although most are commensal and belong to the normal microbiota of human skin and mucous membranes. The most important pathogenic species of this genus are S. pyogenes, S. agalactiae and S. pneumoniae. The genus Enterococcus comprises a group of microorganisms of great relevance due to their role as the main causative agents of healthcare-associated infections. Most infections are caused by two species: Enterococcus faecalis and Enterococcus faecium. They can cause infections such as bacteremia, endocarditis, urinary tract infection or skin-related infections. Both species of the genus Enterococcus have intrinsic resistance to some antimicrobials, mainly cephalosporins, aminoglycosides, clindamycin and trimethoprim-sulfamethoxazole. Laboratory diagnosis of both genera is usually performed by microscopy, culture and in some cases molecular techniques.