title: [Pathogenesis of beta-lactam-resistant Haemophilus influenzae isolated from sputum].
abstract: Haemophlus influenzae persists in the respiratory tract and sometimes causes respiratory tract infections. To evaluate the pathogenesis of beta-lactam-resistant Haemophilus influenzae, we classified 193 Haemophilus influenzae strains isolated from sputum of patients with respiratory tract disease in 24 beta-lactamase positive (BLP) strains, 65 beta-lactamase negative ampicillin resistant (BLNAR) strains and 104 beta-lactamase negative ampicillin sensitive (BLNAS) strains and reviewed the pathogenesis of the strains. The pathogenesis of the strains was evaluated as definite pathogen, presumptive pathogen, colonization and contamination. It was judged to be the definite pathogen that many bacteria isolated from high quality sputum of the patients with respiratory tract infections. Presumptive pathogen was considered to be the bacteria provided from the patient with respiratory infections when the quality of the sputum or quantity of bacteria did not satisfy superscription basis. We considered the bacteria to be colonization or contamination isolated from patients without infections. The breakdown of definite pathogen/presumptive pathogen/colonization/contamination in each by groups was BLP (8/4/8/4), BLNAR (26/14/15/10), BLNAS (36/20/31/17). The ratio of definite or presumptive pathogen was 50% in BLP, 62% in BLNAR and 54% in BLNAS and the significant difference was not recognized in these. Pathogenesis of beta-lactam-resistant Haemophilus influenzae is estimated to be equal with beta-lactam-sensitive Haemophilus influenzae.
authors.affiliation: Department of Respiratory Disease, Kanagawa Cardiovascular and Respiratory Diseases Center.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Watanuki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Odagiri
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Ogura
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Tomioka
mesh_terms: D000328:Adult; D000368:Aged; D000668:Ampicillin Resistance; D005260:Female; D006193:Haemophilus influenzae / Q000201:enzymology / Q000302:isolation & purification* / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012141:Respiratory Tract Infections / Q000382:microbiology*; D013183:Sputum / Q000382:microbiology*; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D001618:beta-Lactamases