The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combi... more The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combination with tazobactam (TAZ) were determined against 168 anaerobes. All the strains were inhibited by PIP + TAZ, but certain strains resistant to CTX + TAZ were found among B. fragilis, Eubacterium and Peptostreptococcus. The second investigations included 30 strains of Bacteroides fragilis. Concentrations of 2, 4 and 8 mg/l of TAZ and sulbactam (SUL) were combined with piperacillin or cefotaxime. The two beta-lactamase-inhibitors had similar activities when used at 2 or 4 mg/l, but at 8 mg/l TAZ was more active than SUL. All B. fragilis strains were inhibited by PIP + TAZ or PIP + SUL, whereas resistance was observed with CTX + SUL or CTX + TAZ. On the same strains the activities of 6 beta-lactams (PIP, mezlocillin, ticarcillin (TIC), CTX, ceftriaxone and ceftazidime) were determined in combination with either SUL 4 mg/l or TAZ 8 mg/l. Only PIP or TIC + SUL or TAZ were able to inhibit a...
The in-vitro antibacterial activity of roxithromycin was assessed by an agar dilution method agai... more The in-vitro antibacterial activity of roxithromycin was assessed by an agar dilution method against 900 recent clinical anaerobic isolates by five laboratories in England, France, Germany and Japan. Roxithromycin had similar activity to erythromycin against most anaerobic bacteria, the latter being slightly more active against Gram-negative bacilli. Roxithromycin inhibited 53% of the Bacteroides fragilis group strains; the noticeable exception was Bact. thetaiotaomicron, only 17% of strains of which were inhibited by 4 mg/l roxithromycin. In contrast, all isolates of Bacteroides, other than the Bact. fragilis group, and all Mobiluncus isolates were inhibited by 2 mg/l of roxithromycin or less. This compound was inactive against half the Fusobacterium strains. Roxithromycin and erythromycin inhibited 65 and 72%, respectively, of 436 strains of Gram-negative anaerobes (MIC less than or equal to 4 mg/l). Roxithromycin suppressed 97% of non-sporulating Gram-positive to bacilli, 86% of Peptococcoaceae and 95% of clostridia. Two-thirds of Clostridium difficile strains were susceptible to roxithromycin (MIC less than or equal to 1 mg/l). The activity of roxithromycin against Gram-positive bacilli was identical to that of erythromycin. Overall a concentration of 4 mg/l roxithromycin and erythromycin inhibited 79 and 83%, respectively, of the strains investigated.
The relationship between susceptibility testing by an agar dilution test and a tablet diffusion t... more The relationship between susceptibility testing by an agar dilution test and a tablet diffusion test was studied for 60 anaerobic bacteria (20 B. fragilis, 20 anaerobic cocci, 20 Clostridium species). For cefoxitin, no prediffusion and prediffusion times of one h, three h, 12 h, 24 h and 48 h were examined. For metronidazole, erythromycin, clindamycin, penicillin and imipenem, only 24 h prediffusion and no prediffusion were studied. Measurements were made after incubation for 24 h and 48 h. Prediffusion improved the correlation for all antibiotics tested, and 24 h prediffusion gave the best results. The slope of the regression line increased and the influence of the individual growth parameters on zone size was reduced. Prediction of susceptibility based on three zone size breakpoints to estimate MIC was also better with 24 h prediffusion. However, the variation about the regression line for many of the antibiotics was still extremely high. Measurements after 24 h and 48 h incubation times showed almost identical regression equations, except for erythromycin, where the regression lines differed.
As recommended by the EEC, the in vitro activity of a veterinary quinolone has to be evaluated on... more As recommended by the EEC, the in vitro activity of a veterinary quinolone has to be evaluated on human strains isolated from the gut and especially against anaerobes. Thus, the MICs for Marbofloxacin were determined by the reference agar method (Norma NCCLS M11 A3) using Wilkins Chalgren medium for the 124 anaerobic strains and Mueller Hinton agar for E. coli, Proteus, Enterococcus and Lactobacillus. On the whole aerobes, the activity of Marbofloxacin was equal or slightly greater to that of ofloxacin. The modal MIC was 0.03 mg/l for Enterobacteriaceae, 2 mg/l and 16 mg/l for Enterococcus and Lactobacillus strains, respectively. Considering the anti-anaerobic activity of this new drug, in comparison with that of ofloxacin, MICs for ofloxacin were generally one log2 higher for Gram negative bacilli and two log2 higher for Gram positive bacilli. Modal MICs for marbofloxacin were 0.12 mg/l for Clostridium perfringens, 0.5 mg/l for Bacteroides fragilis, Fusobacterium, Prevotella, and P...
Antibiotic susceptibility testing of anaerobes by a same methodology allows the authors to draw u... more Antibiotic susceptibility testing of anaerobes by a same methodology allows the authors to draw up suggestions about the evolution of antibiotic resistance within the B. fragilis group. Cefoxitin resistance rates were stable until 1985 and were slowly increasing later. Until 1985 piperacillin was able to inhibit all tested strains. In 1987 the two groups noticed an increasing resistance to piperacillin (4 to 9%). During the 1970's clindamycin resistance was a minor event (less than 1%) then the resistance rate increased rapidly to 10% in 1980. MICs determinations from 1981 to 1985 demonstrated well that clindamycin resistance was stable at this 10% rate. Since 1987 the clindamycin resistance was again increasing and reached respectively 14 to 19% for the two groups of investigators. Metronidazole has kept a good activity against Bacteroides fragilis group strains but some strains with reduced susceptibility (MIC 2 to 8 mg/l) have been described since 1983. Three strains with MIC...
Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-f... more Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-fold dilution in Wilkins - Chalgren agar following the reference method proposed by Sutter et al. No resistance was observed with thienamycin, which is especially active against the Bacteroides fragilis group (MIC 50 = 0.125 mg/l). Among the beta-lactams investigated, cefoxitin and moxalactam proved more active than ceftizoxime and ceftriaxone, while cefotiam exhibited poor activity. While most Fusobacteria were susceptible to studied beta-lactams, some Fusobacterium varium demonstrated resistance to cephalosporins and cephamycins .
The in vitro activity of a new cephalosporin (CPX) was assessed against 260 strains of anaerobic ... more The in vitro activity of a new cephalosporin (CPX) was assessed against 260 strains of anaerobic bacteria. A comparison was done with two other oral cephalosporins cefaclor (CFA) and cefuroxime (CXM). MICs were determined by an agar-dilution method on wilkins chalgren agar. The three antibiotics had little activity against Bacteroïdes fragilis group. Cefpodoxime was more active than the two other cephalosporins against Fusobacterium and Bacteroïdes spp. At 4 mg/l concentration the percentages of susceptibility were respectively CFA 8% CXM 11% for all the Gram negative bacilli. Inversely, a better activity was detected against Gram positive anaerobes; the three cephalosporins inhibiting respectively CFA 65% CXM 75% CFX 46% of 94 tested strains. All Veillonella spp. and Propionibacteria were inhibited by cefpodoxime 4 mg/l. The activity of the three cephalosporins were similar weak against Gram negative anaerobes but greater against Gram positive strict anaerobes.
The aim of this work was to assess the commensal flora in the adult middle meatus. Thus, 139 samp... more The aim of this work was to assess the commensal flora in the adult middle meatus. Thus, 139 samples were taken from subjects of both sexes, over 16 years of age, seen in the community or hospitalized for less than 72 hours for non-rhinological conditions. They had had no nasal or sinus conditions in the previous three months. One hundred and thirteen samples contained at least one aerobic or anaerobic bacterium. Fifty-nine samples yielded a single organism in culture. A maximum of five organisms were isolated from a given patient. These results show that the adult middle meatus contains a mixed commensal flora and should prove useful in interpreting endonasal swab cultures during acute and chronic sinus infection.
The need for predicting bacteriological and clinical antibiotic activity appeared early after dev... more The need for predicting bacteriological and clinical antibiotic activity appeared early after development of the first antibiotics. Antimicrobial efficacy is significant among many therapeutic management factors, including surgery, drug interactions and non-antibiotic therapies. Clinical efficacy is not only related to antimicrobial efficacy, but also to host characteristics and causative organism attributes. Because all these factors interact to achieve success or failure in the management of a given infected patient, to model an n-factor in vivo system from n'-factors in vitro may be difficult.
Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-f... more Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-fold dilution in Wilkins - Chalgren agar following the reference method proposed by Sutter et al. No resistance was observed with thienamycin, which is especially active against the Bacteroides fragilis group (MIC 50 = 0.125 mg/l). Among the beta-lactams investigated, cefoxitin and moxalactam proved more active than ceftizoxime and ceftriaxone, while cefotiam exhibited poor activity. While most Fusobacteria were susceptible to studied beta-lactams, some Fusobacterium varium demonstrated resistance to cephalosporins and cephamycins .
El papel de los anaerobios estrictos y principalmente el de la Prevotella y de las Porphyromonas ... more El papel de los anaerobios estrictos y principalmente el de la Prevotella y de las Porphyromonas esta perfectamente establecido en el curso de las patologias periodontales destructivas. La aparicion durante los tratamientos de cepas resistentes a la tetraciclina, la accion insuficiente del metronidazol y de la clindamicina sobre las cepas que acompanan a los anaerobios (Eikenella, Actinobacilus), hacen que se vuelva hacia diversas asociaciones de antibioticos. Las penicilinas son activas si no las destruyen las B lactamasas producidas por numerosas especies bacterianas. Los inhibidores de B lactamasa asociados a las penicilinas hacen que esto tenga un gran interes. Asi el acido clavulanico al bloquear las B lactamasas de los anaerobios y de cepas de Eikenella, devuelve a la amoxicilina su actividad inicial. Ademas, la accion intrinseca de los inhibidores sobre los anaerobios hace que la accion sea sinergica incluso sobre especies no productoras de B lactamasa. Finalmente contribuyen...
Garlic, onion and shallot were tested for antimicrobial activity against pathogenic aerobic and a... more Garlic, onion and shallot were tested for antimicrobial activity against pathogenic aerobic and anaerobic bacteria. The MIC of aqueous and petroleum ether extracts were determined. Garlic showed the greater activity; the combination garlic-antibiotic is synergistic against Acinetobacter calcoaceticus and leads to indifference against anaerobic bacteria. The active constituent is not probably allicin alone.
The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combi... more The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combination with tazobactam (TAZ) were determined against 168 anaerobes. All the strains were inhibited by PIP + TAZ, but certain strains resistant to CTX + TAZ were found among B. fragilis, Eubacterium and Peptostreptococcus. The second investigations included 30 strains of Bacteroides fragilis. Concentrations of 2, 4 and 8 mg/l of TAZ and sulbactam (SUL) were combined with piperacillin or cefotaxime. The two beta-lactamase-inhibitors had similar activities when used at 2 or 4 mg/l, but at 8 mg/l TAZ was more active than SUL. All B. fragilis strains were inhibited by PIP + TAZ or PIP + SUL, whereas resistance was observed with CTX + SUL or CTX + TAZ. On the same strains the activities of 6 beta-lactams (PIP, mezlocillin, ticarcillin (TIC), CTX, ceftriaxone and ceftazidime) were determined in combination with either SUL 4 mg/l or TAZ 8 mg/l. Only PIP or TIC + SUL or TAZ were able to inhibit a...
The in-vitro antibacterial activity of roxithromycin was assessed by an agar dilution method agai... more The in-vitro antibacterial activity of roxithromycin was assessed by an agar dilution method against 900 recent clinical anaerobic isolates by five laboratories in England, France, Germany and Japan. Roxithromycin had similar activity to erythromycin against most anaerobic bacteria, the latter being slightly more active against Gram-negative bacilli. Roxithromycin inhibited 53% of the Bacteroides fragilis group strains; the noticeable exception was Bact. thetaiotaomicron, only 17% of strains of which were inhibited by 4 mg/l roxithromycin. In contrast, all isolates of Bacteroides, other than the Bact. fragilis group, and all Mobiluncus isolates were inhibited by 2 mg/l of roxithromycin or less. This compound was inactive against half the Fusobacterium strains. Roxithromycin and erythromycin inhibited 65 and 72%, respectively, of 436 strains of Gram-negative anaerobes (MIC less than or equal to 4 mg/l). Roxithromycin suppressed 97% of non-sporulating Gram-positive to bacilli, 86% of Peptococcoaceae and 95% of clostridia. Two-thirds of Clostridium difficile strains were susceptible to roxithromycin (MIC less than or equal to 1 mg/l). The activity of roxithromycin against Gram-positive bacilli was identical to that of erythromycin. Overall a concentration of 4 mg/l roxithromycin and erythromycin inhibited 79 and 83%, respectively, of the strains investigated.
The relationship between susceptibility testing by an agar dilution test and a tablet diffusion t... more The relationship between susceptibility testing by an agar dilution test and a tablet diffusion test was studied for 60 anaerobic bacteria (20 B. fragilis, 20 anaerobic cocci, 20 Clostridium species). For cefoxitin, no prediffusion and prediffusion times of one h, three h, 12 h, 24 h and 48 h were examined. For metronidazole, erythromycin, clindamycin, penicillin and imipenem, only 24 h prediffusion and no prediffusion were studied. Measurements were made after incubation for 24 h and 48 h. Prediffusion improved the correlation for all antibiotics tested, and 24 h prediffusion gave the best results. The slope of the regression line increased and the influence of the individual growth parameters on zone size was reduced. Prediction of susceptibility based on three zone size breakpoints to estimate MIC was also better with 24 h prediffusion. However, the variation about the regression line for many of the antibiotics was still extremely high. Measurements after 24 h and 48 h incubation times showed almost identical regression equations, except for erythromycin, where the regression lines differed.
As recommended by the EEC, the in vitro activity of a veterinary quinolone has to be evaluated on... more As recommended by the EEC, the in vitro activity of a veterinary quinolone has to be evaluated on human strains isolated from the gut and especially against anaerobes. Thus, the MICs for Marbofloxacin were determined by the reference agar method (Norma NCCLS M11 A3) using Wilkins Chalgren medium for the 124 anaerobic strains and Mueller Hinton agar for E. coli, Proteus, Enterococcus and Lactobacillus. On the whole aerobes, the activity of Marbofloxacin was equal or slightly greater to that of ofloxacin. The modal MIC was 0.03 mg/l for Enterobacteriaceae, 2 mg/l and 16 mg/l for Enterococcus and Lactobacillus strains, respectively. Considering the anti-anaerobic activity of this new drug, in comparison with that of ofloxacin, MICs for ofloxacin were generally one log2 higher for Gram negative bacilli and two log2 higher for Gram positive bacilli. Modal MICs for marbofloxacin were 0.12 mg/l for Clostridium perfringens, 0.5 mg/l for Bacteroides fragilis, Fusobacterium, Prevotella, and P...
Antibiotic susceptibility testing of anaerobes by a same methodology allows the authors to draw u... more Antibiotic susceptibility testing of anaerobes by a same methodology allows the authors to draw up suggestions about the evolution of antibiotic resistance within the B. fragilis group. Cefoxitin resistance rates were stable until 1985 and were slowly increasing later. Until 1985 piperacillin was able to inhibit all tested strains. In 1987 the two groups noticed an increasing resistance to piperacillin (4 to 9%). During the 1970's clindamycin resistance was a minor event (less than 1%) then the resistance rate increased rapidly to 10% in 1980. MICs determinations from 1981 to 1985 demonstrated well that clindamycin resistance was stable at this 10% rate. Since 1987 the clindamycin resistance was again increasing and reached respectively 14 to 19% for the two groups of investigators. Metronidazole has kept a good activity against Bacteroides fragilis group strains but some strains with reduced susceptibility (MIC 2 to 8 mg/l) have been described since 1983. Three strains with MIC...
Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-f... more Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-fold dilution in Wilkins - Chalgren agar following the reference method proposed by Sutter et al. No resistance was observed with thienamycin, which is especially active against the Bacteroides fragilis group (MIC 50 = 0.125 mg/l). Among the beta-lactams investigated, cefoxitin and moxalactam proved more active than ceftizoxime and ceftriaxone, while cefotiam exhibited poor activity. While most Fusobacteria were susceptible to studied beta-lactams, some Fusobacterium varium demonstrated resistance to cephalosporins and cephamycins .
The in vitro activity of a new cephalosporin (CPX) was assessed against 260 strains of anaerobic ... more The in vitro activity of a new cephalosporin (CPX) was assessed against 260 strains of anaerobic bacteria. A comparison was done with two other oral cephalosporins cefaclor (CFA) and cefuroxime (CXM). MICs were determined by an agar-dilution method on wilkins chalgren agar. The three antibiotics had little activity against Bacteroïdes fragilis group. Cefpodoxime was more active than the two other cephalosporins against Fusobacterium and Bacteroïdes spp. At 4 mg/l concentration the percentages of susceptibility were respectively CFA 8% CXM 11% for all the Gram negative bacilli. Inversely, a better activity was detected against Gram positive anaerobes; the three cephalosporins inhibiting respectively CFA 65% CXM 75% CFX 46% of 94 tested strains. All Veillonella spp. and Propionibacteria were inhibited by cefpodoxime 4 mg/l. The activity of the three cephalosporins were similar weak against Gram negative anaerobes but greater against Gram positive strict anaerobes.
The aim of this work was to assess the commensal flora in the adult middle meatus. Thus, 139 samp... more The aim of this work was to assess the commensal flora in the adult middle meatus. Thus, 139 samples were taken from subjects of both sexes, over 16 years of age, seen in the community or hospitalized for less than 72 hours for non-rhinological conditions. They had had no nasal or sinus conditions in the previous three months. One hundred and thirteen samples contained at least one aerobic or anaerobic bacterium. Fifty-nine samples yielded a single organism in culture. A maximum of five organisms were isolated from a given patient. These results show that the adult middle meatus contains a mixed commensal flora and should prove useful in interpreting endonasal swab cultures during acute and chronic sinus infection.
The need for predicting bacteriological and clinical antibiotic activity appeared early after dev... more The need for predicting bacteriological and clinical antibiotic activity appeared early after development of the first antibiotics. Antimicrobial efficacy is significant among many therapeutic management factors, including surgery, drug interactions and non-antibiotic therapies. Clinical efficacy is not only related to antimicrobial efficacy, but also to host characteristics and causative organism attributes. Because all these factors interact to achieve success or failure in the management of a given infected patient, to model an n-factor in vivo system from n'-factors in vitro may be difficult.
Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-f... more Minimal inhibitory concentrations of 105 anaerobic Gram negative bacilli were determined by two-fold dilution in Wilkins - Chalgren agar following the reference method proposed by Sutter et al. No resistance was observed with thienamycin, which is especially active against the Bacteroides fragilis group (MIC 50 = 0.125 mg/l). Among the beta-lactams investigated, cefoxitin and moxalactam proved more active than ceftizoxime and ceftriaxone, while cefotiam exhibited poor activity. While most Fusobacteria were susceptible to studied beta-lactams, some Fusobacterium varium demonstrated resistance to cephalosporins and cephamycins .
El papel de los anaerobios estrictos y principalmente el de la Prevotella y de las Porphyromonas ... more El papel de los anaerobios estrictos y principalmente el de la Prevotella y de las Porphyromonas esta perfectamente establecido en el curso de las patologias periodontales destructivas. La aparicion durante los tratamientos de cepas resistentes a la tetraciclina, la accion insuficiente del metronidazol y de la clindamicina sobre las cepas que acompanan a los anaerobios (Eikenella, Actinobacilus), hacen que se vuelva hacia diversas asociaciones de antibioticos. Las penicilinas son activas si no las destruyen las B lactamasas producidas por numerosas especies bacterianas. Los inhibidores de B lactamasa asociados a las penicilinas hacen que esto tenga un gran interes. Asi el acido clavulanico al bloquear las B lactamasas de los anaerobios y de cepas de Eikenella, devuelve a la amoxicilina su actividad inicial. Ademas, la accion intrinseca de los inhibidores sobre los anaerobios hace que la accion sea sinergica incluso sobre especies no productoras de B lactamasa. Finalmente contribuyen...
Garlic, onion and shallot were tested for antimicrobial activity against pathogenic aerobic and a... more Garlic, onion and shallot were tested for antimicrobial activity against pathogenic aerobic and anaerobic bacteria. The MIC of aqueous and petroleum ether extracts were determined. Garlic showed the greater activity; the combination garlic-antibiotic is synergistic against Acinetobacter calcoaceticus and leads to indifference against anaerobic bacteria. The active constituent is not probably allicin alone.
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