PDF《Prevalence of b-lactamase-》

Oral Microbiol Immunol 1999: 14: 352C357 Copyright C Munksgaard

1999 Printed in Denmark .

All rights reserved ISSN 0902-0055 T. Fosse1 , I. Madinier1,2 , C. Hitzig3 , Y. Charbit3 Prevalence of b-lactamase-

1 Laboratoire de Bacte ?riologie, Ho ?pital l'

Archet 2, CHU de Nice,

2 Faculte ? de Chirurgie- Dentaire,

3 De ?partement de Parodontologie, producing strains among

149 Faculte ? de Chirurgie-Dentaire, Universite ? de Nice Sophia Antipolis, France anaerobic gram-negative rods isolated from periodontal pockets Fosse T, Madinier I, Hitzig C, Charbit Y. Prevalence of b-lactamase-producing strains among

149 anaerobic gram-negative rods isolated from periodontal pockets. Oral Microbiol Immunol 1999: 14: 352C357. C Munksgaard, 1999. In a prospective study,

47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of b-lactamase-producing strains among oral anaerobic gram-negative rods. Predominant anaerobes were identi?ed from two of the deepest periodontal pockets. b-Lactamase-positive strains ful?lled to at least two of three criteria: positive nitroce?n test, penicillin Etest minimal inhibitory concentration?1 mg/ml, and disk diffusion synergy between amoxycillin and clavulanic acid?10 mm. At least one b-lactamase- producing strain was found in 53.2% of patients and 39.4% of the periodontal pockets investigated. Prominent b-lactamase-positive species were Prevotella buccae and Prevotella intermedia (respectively

16 of 38: 42% and

18 of 52: 35% positive strains), followed by Prevotella bivia, Prevotella disiens, Prevotella Key words: anaerobes;

b-lactamase;

oral;

denticola and Fusobacterium nucleatum (respectively

1 of 6: 17%,

1 of 10: 10%,

1 Prevotella;

resistance of 10: 10%, and

1 of 13: 8% positive strains). No b-lactamase producer could be T. Fosse, Laboratoire de Bacte ?riologie, evidenced in Porphyromonas gingivalis (10 strains tested). All the b-lactamase- Ho ?pital l'

Archet 2, CHU de Nice, BP 79, positive strains with the nitroce?n test had penicillin minimal inhibitory

06202 Nice Cedex 3, France concentrations?1 mg/ml with the Etest, and a strong synergy between amoxicillin and clavulanic acid was always observed. Accepted for publication February 23,

1999 Gram-negative anaerobic rods are major components of the normal oral ?ora, but under certain conditions, in- cluding destruction of tissues, poor cir- culation or impaired host defense, they may be responsible of local or dissemi- nated infections (29, 34, 48). In local oral infections (periodontal diseases, gingivitis, pericoronitis, endodontitis, peri-implantitis and post-extraction in- fections) as well as in systemic infec- tions such as pulmonary infections, brain abcess or mediastinitis, oral an- aerobes are frequently associated in po- lybacterial suppurative processes (32, 37). Odontogenic local infections re- quire surgical treatment and, if necess- ary, a probabilistic antibiotherapy effec- tive on mostly recognized oral patho- gens (21, 50). Anaerobes are naturally resistant to aminoglycosides and older ?uoroquinolones, and they are increas- ingly resistant to antibiotics as their use have become more widespread, especi- ally to b-lactam compounds (2, 11, 12, 41). b-Lactamases are the major cause of bacterial resistance to b-lactam anti- biotics and have been the subject of ex- tensive microbiological, biochemical and genetic investigations. b-Lactam- ases are found in most bacterial species and may have evolved primarily to pro- tect soil bacteria from production of b-lactams by other microorganisms (fungi, actinomycetes and other bac- teria) (8, 9). A structural classi?cation of the b-lactamases has been proposed to differentiate enzymes with a serine residue in the active site (serine b-lac- tamases) from enzymes with zinc-con- taining active site (metallo-b-lactamas- es) (1). A more complex functional classi?cation has been proposed, based upon substrate pro?le and upon ability to be inhibited by active site-directed suicide inhibitors (clavulanic acid, tazo- bactam and sulbactam) or by protein- modifying agents such as EDTA or p- chloromercurybenzoate (pCMB) (8, 9). b-Lactamase inhibitors are second line drugs recently developed in order to in- activate b-lactamases (53). Special attention has been paid to the clinically important Bacteroides, Prevotella and b-Lactamases in oral anaerobes