title: Repeated bacteraemia caused by Streptococcus mutans in a patient with Sjogren's syndrome.
abstract: Streptococcus mutans, considered to be a pathogen for dental caries, is known to cause bacteraemia and infective endocarditis. Herein, an unusual case of repeated bacteraemia caused by S. mutans identified in a 71-year-old male is described. The patient visited Itami City Hospital with the major complaint of a fever, and a subsequent clinical examination led to a diagnosis of possible infective endocarditis without specific vegetation formation around the heart valve. A bacteriological examination of blood taken at the first visit showed the presence of S. mutans. Antimicrobial treatment was provided, which successfully eliminated the pathogenic bacteria from the blood. However, the patient returned and was hospitalized twice more with a recurrent fever, and S. mutans was again detected. Analyses of the biological properties of the S. mutans isolates showed that they possessed cariogenic properties and had a low susceptibility to phagocytosis by human polymorphonuclear leukocytes. Since the patient had Sjögren's syndrome, in which a reduction of saliva secretion is a characteristic feature, a great number of dental caries lesions were identified. The findings indicated that S. mutans present in those dental caries lesions caused repeated bacteraemia in this case.
authors.affiliation: Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Nomura
authors.affiliation: Department of Dentistry and Oral Surgery, Itami City Hospital, Itami, Hyogo 664-8540, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hamada
authors.affiliation: Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakano
authors.affiliation: Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Nemoto
authors.affiliation: Department of Dentistry and Oral Surgery, Itami City Hospital, Itami, Hyogo 664-8540, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Fujimoto
authors.affiliation: Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ooshima
mesh_terms: D000368:Aged; D016470:Bacteremia / Q000382:microbiology* / Q000517:prevention & control; D003731:Dental Caries / Q000150:complications / Q000382:microbiology*; D006801:Humans; D008297:Male; D012008:Recurrence; D012859:Sjogren's Syndrome / Q000150:complications*; D013290:Streptococcal Infections / Q000150:complications / Q000382:microbiology* / Q000517:prevention & control; D013295:Streptococcus mutans / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*