[Erysipelas: microbiological and pathogenic data].

Streptococcus pyogenes is considered as the primary cause of erysipelas and the virulence factors of this species are reviewed. The role of Staphylococcus aureus alone or associated with Streptococcus pyogenes remains unclear. Other etiologies are infrequent. Several techniques were used to detect bacteria (direct examination, culture, antigen or genome assay) in local samples (needle aspiration, swab.), in others sites (throat, blood cultures), or specific antibodies. The performance of the various diagnosis methods is evaluated. Despite the combination of 2 or more methods, the etiology remains unknown in almost 20 p. 100 of the cases.