title: Acute abdomen due to group A streptococcus bacteremia caused by an isolate with a mutation in the csrS gene.
abstract: Streptococcus pyogenes (group A streptococcus) is an aerobic gram-positive coccus that causes infections ranging from non-invasive pharyngitis to severely invasive necrotizing fasciitis. Mutations in csrS/csrR and rgg, negative regulator genes of group A streptococcus, are crucial factors in the pathogenesis of streptococcal toxic shock syndrome, which is a severe, invasive infection characterized by sudden onset of shock and multiorgan failure, resulting in a high mortality rate. Here we present a case of group A streptococcal bacteremia in a 28-year-old Japanese woman with no relevant previous medical history. The patient developed progressive abdominal symptoms that may have been due to spontaneous bacterial peritonitis, followed by a state of shock, which did not fulfill the proposed criteria for streptococcal toxic shock. The isolate was found to harbor a mutation in the negative regulator csrS gene, whereas the csrR and rgg genes were intact. It was noteworthy that this strain carrying a csrS mutation had caused group A streptococcal bacteremia characterized by acute abdomen as the presenting symptom in a young individual who had been previously healthy. This case indicates that group A streptococcus with csrS mutations has potential virulence factors that are associated with the onset of group A streptococcal bacteremia that does not meet the diagnostic criteria for streptococcal toxic shock syndrome.
authors.affiliation: Department of Internal Medicine, Uwajima City Hospital, 1-1 Goten-machi, Uwajima City, Ehime 798-8510, Japan. Electronic address: kaneko@uwajima-mh.jp.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kaneko
authors.affiliation: Department of Internal Medicine, Uwajima City Hospital, 1-1 Goten-machi, Uwajima City, Ehime 798-8510, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Maruta
authors.affiliation: Department of Internal Medicine, Uwajima City Hospital, 1-1 Goten-machi, Uwajima City, Ehime 798-8510, Japan.
authors.forename: Hisaharu
authors.initials: H
authors.lastname: Shikata
authors.affiliation: Department of Internal Medicine, Uwajima City Hospital, 1-1 Goten-machi, Uwajima City, Ehime 798-8510, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hanayama
authors.affiliation: Department of Bacteriology 1, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-Ku, Tokyo 162-8640, Japan.
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Ikebe
mesh_terms: D000006:Abdomen, Acute / Q000150:complications / Q000382:microbiology*; D000328:Adult; D016470:Bacteremia / Q000150:complications / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D006801:Humans; D009154:Mutation / Q000235:genetics*; D011494:Protein Kinases / Q000235:genetics*; D013290:Streptococcal Infections / Q000150:complications / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D011494:Protein Kinases; C432144:CsrS protein, bacteria
keywords: Acute abdomen; Group A streptococcus bacteremia; Streptococcal toxic shock syndrome; csrS gene mutation