title: beta-Lactamase activity in sputum and indirect pathogenicity.
abstract: beta-Lactamase activity of sputum of 39 patients with respiratory infections and that of bacterial isolates from their sputum were determined by nitrocefin method. Forty-six microbial strains (16 different species) were recovered from 39 sputum samples. The beta-lactamase activity was negative only in nine of the 46 strains. beta-lactamase-positive strains were recovered from 35 of 39 sputum samples. Of these 35 sputum samples, the beta-lactamase activity was positive in 23 and negative in 12. beta-lactamase-negative strains were recovered from 4 of 39 sputum samples, and the beta-lactamase activity was negative in all of these four sputum samples. Both beta-lactamase producing and non-producing strains were recovered in 5 of 6 sputum samples from which two to three microbes were isolated. The ratio of beta-lactamase-positive sputum sample was higher in patients who had received antibiotics than in those who had received no antibiotics. This difference was statistically significant (P < 0.025). It is possible that non-causative beta-lactamase-positive organisms enhance the pathogenicity of causative organisms that are beta-lactamase-negative.
authors.affiliation: Department of Internal Medicine, Tohoku University, Sendai, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Watanabe
authors.forename: K
authors.initials: K
authors.lastname: Oizumi
authors.forename: M
authors.initials: M
authors.lastname: Motomiya
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D012141:Respiratory Tract Infections / Q000382:microbiology; D013183:Sputum / Q000201:enzymology* / Q000382:microbiology; D001618:beta-Lactamases / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases