title: Erysipelas caused by group A streptococcus activates the contact system and induces the release of heparin-binding protein.
abstract: Bacterial skin infections, such as erysipelas or cellulitis, are characterized by fever and a painful erythematous rash. Despite the high prevalence of these infections, little is known about the underlying pathogenic mechanisms. This is partly due to the fact that a bacterial diagnosis is often difficult to attain. To gain insight into the pathogenesis of erysipelas, we investigated the samples obtained from infected and noninfected areas of skin from 12 patients with erysipelas. Bacterial cultures, detection of specific streptococcal antibodies in convalescent sera, and immunohistochemical analyses of biopsies indicated group A streptococcal etiology in 11 of the 12 patients. Also, electron micrographs of erythematous skin confirmed the presence of group A streptococcal cells and showed a limited solubilization of the surface-attached M protein. Degradation of high-molecular-weight kininogen and upregulation of the bradykinin-1 receptor in inflamed tissues indicated activation of the contact system in 11 patients. Analyses of release of the vasoactive heparin-binding protein (HBP) showed increased levels in the infected as compared with the noninfected areas. The results suggest that group A streptococci induce contact activation and HBP release during skin infection, which likely contribute to the symptoms seen in erysipelas: fever, pain, erythema, and edema.
authors.affiliation: Division of Infection Medicine, Department of Clinical Sciences, Lund University Hospital, Lund, Sweden.
authors.forename: Adam
authors.initials: A
authors.lastname: Linder
authors.forename: Linda
authors.initials: L
authors.lastname: Johansson
authors.forename: Pontus
authors.initials: P
authors.lastname: Thulin
authors.forename: Erika
authors.initials: E
authors.lastname: Hertzén
authors.forename: Matthias
authors.initials: M
authors.lastname: Mörgelin
authors.forename: Bertil
authors.initials: B
authors.lastname: Christensson
authors.forename: Lars
authors.initials: L
authors.lastname: Björck
authors.forename: Anna
authors.initials: A
authors.lastname: Norrby-Teglund
authors.forename: Per
authors.initials: P
authors.lastname: Akesson
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000276:immunology / Q000378:metabolism; D023181:Antimicrobial Cationic Peptides / Q000276:immunology / Q000378:metabolism*; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001706:Biopsy; D001798:Blood Proteins / Q000276:immunology / Q000378:metabolism*; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism*; D004886:Erysipelas / Q000276:immunology* / Q000382:microbiology* / Q000473:pathology; D006801:Humans; D019679:Kininogen, High-Molecular-Weight / Q000378:metabolism; D008854:Microscopy, Electron; D008875:Middle Aged; D043783:Receptor, Bradykinin B1 / Q000378:metabolism; D012867:Skin / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D013290:Streptococcal Infections / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D013297:Streptococcus pyogenes / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: C062991:AZU1 protein, human; D000942:Antigens, Bacterial; D023181:Antimicrobial Cationic Peptides; D001425:Bacterial Outer Membrane Proteins; D001798:Blood Proteins; D002352:Carrier Proteins; D019679:Kininogen, High-Molecular-Weight; D043783:Receptor, Bradykinin B1; C014689:streptococcal M protein