title: beta-Lactamase producing bacteria in adult periodontitis.
abstract: In 23 untreated adult periodontitis patients, the occurrence of beta-lactamase producing periodontal bacteria was determined. In addition to non-selective isolation media, selective isolation and growth of beta-lactamase positive subgingival bacterial species was carried out on blood agar plates supplemented with amoxicillin and plates with amoxicillin+clavulanic acid. Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Peptostreptococcus micros, Fusobacterium nucleatum, Bacteroides forsythus and Campylobacter rectus isolates from the non-selective medium were tested for beta-lactamase activity by a nitrocefin disk method (DrySlide) and by a laboratory chromogenic nitrocefin-based test. Isolates from the amoxicillin plates that were absent on the amoxicillin/clavulanic acid plates were identified and tested for beta-lactamase production. Based on the non-selective plates, six of 23 P. intermedia isolates, 2 of 19 B. forsythus isolates and 3 of 23 F. nucleatum isolates were beta-lactamase positive. The beta-lactamase positive species Prevotella loescheii, Prevotella buccae, Prevotella buccalis and Actinomyces spp were recovered from the selective amoxicillin plates. beta-Lactamase positive subgingival species were recovered from 17 of 23 patients (74%) but usually comprised low proportions of the subgingival microbiota (range < 0.01-15%). Comparison of the DrySlide test and the nitrocefin-based laboratory test revealed full agreement of test results. beta-Lactamase activity in whole subgingival plaque was detected in 12 patient samples (52%). It was concluded that beta-lactamase activity in subgingival bacteria in adult periodontitis is a common feature. However, since the majority of the samples showed only low-level enzymatic activity, the clinical relevance of this observation with regard to therapy with unprotected enzyme-susceptible beta-lactams is uncertain, though failure on the other hand, is difficult to rule out when a mechanism of resistance is present. The majority of beta-lactamase positive strains was found among species of the Prevotella genus.
authors.affiliation: Academic Centre for Dentistry Amsterdam, The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: van Winkelhoff
authors.forename: E G
authors.initials: EG
authors.lastname: Winkel
authors.forename: D
authors.initials: D
authors.lastname: Barendregt
authors.forename: N
authors.initials: N
authors.lastname: Dellemijn-Kippuw
authors.forename: A
authors.initials: A
authors.lastname: Stijne
authors.forename: U
authors.initials: U
authors.lastname: van der Velden
mesh_terms: D000190:Actinomyces / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D000658:Amoxicillin / Q000378:metabolism; D019980:Amoxicillin-Potassium Clavulanate Combination; D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000627:therapeutic use; D001419:Bacteria / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D001439:Bacteroides / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D002167:Campylobacter / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D002511:Cephalosporins; D002863:Chromogenic Compounds; D002969:Clavulanic Acids / Q000378:metabolism; D003470:Culture Media; D003773:Dental Plaque / Q000201:enzymology / Q000382:microbiology; D016967:Fusobacterium nucleatum / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D005881:Gingiva / Q000382:microbiology; D006801:Humans; D007202:Indicators and Reagents; D010406:Penicillins / Q000378:metabolism; D010462:Peptostreptococcus / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D010518:Periodontitis / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D018720:Prevotella / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D018713:Prevotella intermedia / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D002863:Chromogenic Compounds; D002969:Clavulanic Acids; D003470:Culture Media; D007202:Indicators and Reagents; D010406:Penicillins; D019980:Amoxicillin-Potassium Clavulanate Combination; D000658:Amoxicillin; D001618:beta-Lactamases; C021720:nitrocefin