466
Correspondence
References Centers for Disease Control (1987). Antibiotic-resistant strains of Neisserla gonorrhoeae: policy guidelines for detection, mnnagcment and control. Morbidity Mortality Weekly Report 36, Suppl. 5. 1-18. Centers for Disease Control (1990). Plasmid-mediated antimicrobial resistances in Neisserla gonorrhoeae. United States, 1988 and 1989. Morbidity Mortality Weekly Report 39, 284-93. Fuchs, P. C , Jones, R. N., Barry, A. L. & Thornsberry, C. (1986). Tentative disk diffusion susceptibility interpretive criteria for BMY-28142, a new cephalosporin. Journal of Clinical Microbiology 23, 634-6. Jones, R. N., Fuchs, P. C , Washington, J. A., II, Gavan, T. L., Murray, P. R., Geriach, E H. et al. (1990). Interpretive criteria, quality control guidelines, and drug stability studies for susceptibility testing of cefotaxime, cefoxitin, ceftazidime, and cefuroxime against Neisseria gonorrhoeae. Diagnostic Microbiology and Infectious Disease 13, 499-508. Jones, R. N., Gavan, T. L., Thornsberry, C , Fuchs, P. C , Geriach, E H., Knapp, J. S. et al (1989). Standardization of disk diffusion asd agar dilution susceptibility tests for Neisseria gonorrhoeae: interpretive criteria and quality control guidelines for ceflriaxone, penicillin, spectinomycin, and tetracyctine. Journal of Clinical Microbiology 21, 2756-66.
Kessler, R. E , Bies, M., Buck, R. E., Chishohn, D. R., Pursiano, T. A., Tsai, Y. H. et al. (1985). Comparison of a new cephalosporin, BMY 28142, with other broad-spectrum /Mactam antibiotics. Antimicrobial Agents and Chemotherapy TJ, 207-16. Khan, N. J., Bihi, J. A., Schell, R. F., LeFrock, J. L. & Weber, S. J. (1984). Antimicrobial activities of BMY-28142, cefbuperazone, and cefpiramide compared with those of other cephalospoiins. Antimicrobial Agents and Chemotherapy 26, 585-90. National Committee for Clinical Laboratory Standards (1989). Development of In vitro Susceptibility Testing Criteria and Quality Control Parameters. Tentative Guideline M23-T. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (1990a). Performance Standards for Antimlcrobk Disk Susceptibility Tests. Approved Standard M2-A4. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (19906). Standard Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically. Approved Standard M7-A2. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (1991). Information Supplement, M100-S3. National Committee for Clinical Laboratory Standards, Vulanova, PA. Ringertz, S., Rylander, M. & Kronvall (1991). Disk diffusion method for susceptibility testing of Neisseria gonorrhoeae. Journal of Clinical Microbiology 29, 1604-9.
In-ritro activity of sparfloxadn, pefloxadn, dprofloxadn and temafloxadn against clinical isolates of Acmetobmcter spp. Sir, Over the last ten years, Adnetobacter spp. have become an important cause of hospital acquired infections (Bergogne-Berezin & Jolly-Guillou, 1991). The most frequent infections are outbreaks of respiratory tract infections in ventilated patients, bacteraemia and nosocomial urinary tract infections (Smego, 1985; Vandenbroucke-Grauls et al., 1988). Nosocomial infections with Acinetobacter spp. constitute a difficult therapeutic problem due to a rapid increase in resistance to most newer /J-lactams and aminoglycosides. In 1985-86 a study of the susceptibility of 130 clinical isolates of acinetobacter strains showed very promising results with ciprofloxacin, ofloxacin and pefloxadn (Bergogne-Berezin &
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
liminary guidelines by the Centers for Disease Control (CDC, 1987). Those guidelines were necessary to deal with the documented increase in plasmid-mediated resistances to penicillins and tetracyclines (CDC, 1990). Currently the number of /Mactamase-stable cephalospoiins having NCCLS (1991) interpretive criteria for gonococcal testing includes ceflriaxone, cefotaxime, cefoxitin, ceftazidime, cefuroxime, cefotetan and cefixime. To this list we now add cefepime, a compound with documented high activity against N. gonorrhoeae strains equal to that of other so-called 'third-generation' cephalospoiins (Kessler el al., 1983; Fuchs et al., 1986). Acknowledgements. The following persons contributed significant technical or manuscript processing support to this study: Dr F. Koontz, M. Erwin, M. Barrett, B. Briggs, D. Johnson, and L. Miller. This investigation was made possible by technical grants from G.D. Searle and Co., Lederle Laboratories and Bristol-Myers Squibb. RONALD N. JONES Anti-Infecthes Research Center, Department of Pathology, 5232 RCP, University of Iowa College of Medicine, Iowa City, Iowa 52242 USA
Correspondence (b)
467 CO
^ r
(c)
^
Co
c /
/
.T
_^__
s
^
i
24
^
i
w
1/
1
1
24
24
3 6
Tlmt(h) Figure. Killing curves of Acmtobacter spp. in the presence of pefloxacin (t>)> ciprofloxacin ( Q , temafloxacin (T) and sparfloxacin (S) at one (a), two (b) or four (c) times MIC, compared to control (Co). Table. MICs of fluoroquinolones for Acinetobacter baumanii Compound
Year
Range of MIC« (mg/L)
MIC,,, (mg/L)
MIC, (mg/L)
Geometric mean MlC/(mg/L)
Pefloxacin
1985 1988-89 1990
0-25-16 0125-128 0125- > 128
1-05 141 46-3
6-7 7+6 196
1-6 102 24-3
Ciprofloxacin
1985 1988-89 1990
0016-32 0016-128 003-128
07 7-3 33-7
4-6 6O4 88
O98 5-7 12-5
Ofloxacin
1985 1988-89
006-16 0016-32
3-7 14-6
103 203
Temafloxacin
1988-89 1990
0016-64 003-128
2-8 14-3
41 49
2-8 6-3
Sparfloxacin
1990
003-32
3
7-6
1-6
Joly-Guillou, 1985). A few years later, after the introduction of these new quinolones another investigation was carried out with acinetobacter strains collected in 1988-1989 (Bergogne-Bcrezin & Joly-Guillou, 1989). It was noted that acinetobacter strains had become more resistant to these quinolones. We now report the activity of a new fluorinated quinolone, sparfloxacin, compared with that of
069 3-37
pefloxacin, ciprofloxacin and temafloxacin against acinetobacter strains collected in 1990. Two-fold dilutions of freshly prepared solutions of antimicrobial agents were incorporated into Mueller-Hinton agar to yield final concentrations ranging from 256 to 0-03 mg/L. An inoculum of approximately 106 cfu was applied with a Steers replicator and the plates incubated aerobically at 35°C
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
\
p
s
468
Correspondence
Department of Microbiology, University Hospital Bichat-Claude Bernard, 46 rue Henri-Huchard. 75877-Paris Cedex 18, France
References Bergogne-Berezin, E., Joly-Guillou, M. L. (1985). An underestimated nosocomial pathogen, Acinetobacter calcoaceticus. Journal of Antimicrobial Chemotherapy 16, 535-8. Bergogne-Berfczin, E. & Joly-Guillou, M. L. (1989). Activity of new fluoroquinolona against acinetobacter from nosocomial infection!. Quinolones Bulletin 5, 23-6. Bergogne-Bererin, E. & Joly-Guillou, M. L. (1991). Hospital infection with Acinetobacter spp.: an increasing problem. Journal of Hospital Infection 18,250-5. Smego, R. A. (1985). Endemic nojomial bacteremia. Archives of Internal Medicine 145, 2174-9. Vandenbroucke-Grauls, C. M. J. E., Kerver, A. J. H., Rommet, J. H. Jansen, R., Den Dekker, C. & Verhoef, J. (1988). Endemic Acinetobacter anitratus in a surgical intensive care unit mechanical ventilator! as a reservoir. European Journal of Clinical Microbiology and Infectious Disease 7, 485-9.
In-vttro activity of twefre antibiotics against clinical isolates of Biloptdla wadswortMa Sir, Bilophila wadsworthia is a newly described Gram-negative anaerobic bacillus which was first discovered in the late 1980s by Bennion et al. (1990) in specimens from gangrenous and perforated appendicitis. They found that this organism was the fourth most common anaerobic isolate from specimens obtained from the above patient group; it was also isolated from normal faecal samples. However, B. wadsworthia is a relatively slow-growing anaerobe that produces small, ill-defined colonies and requires a selective medium for its isolation; hence its only recent discovery. A more detailed study on the characterization of B. wadsworthia was carried out by Baron et al. (1989) who described it as strongly catalascpositive, urcase-positive and able to reduce nitrate; moreover, it was stimulated by bile. Previously, there has only been a brief comment on the antimicrobial susceptibility of B. wadsworthia (Bennion et al., 1990) with a more comprehensive report proposed to be reported elsewhere. This is most probably the first report on strains isolated in the United Kingdom. In this study we examined 42 fresh clinical isolates of B. wadsworthia from randomly collected faeces specimens submitted to the Royal Hallamshire Hospital, Sheffield for the investigation of enteric pathogens. Specimens were plated onto either Bacteroides ureolyticus medium (Lab M, Bury, UK) (Eley, Clarry & Bennett, 1989) or Aeromonas medium (Difco, Surrey, UK) and B. wadsworthia identified as described previously, using biochemical tests, API Rapid ID 32A and gas-liquid chromatography (Baron et al., 1989), with further confirmation by sodium dodecyl sulphate polyacrylamide gel dectrophoresis. For comparison we also tested ATCC strain 49260 and two strains isolated from the VA Wadsworth Medical Center, Los Angeles, USA (the original source). MIC determinations were made by an agar dilution method (Jones et al., 1985) using Brain Heart Infusion (BHI) agar supplemented with yeast extract (5 g/L), and containing doubling dilutions of the different antibiotics. Test organisms were grown anaerobically for four days. Growth was harvested and suspended in supplemented BHI broth (as above) to match Wellcome opacity tube no. 1 at a concentration of 109 cfu/mL and diluted 1 in 100. A multipoint inoculator was used to deliver a 1 /iL inoculum containing
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
for 24 h. Kinetic killing curves were determined for susceptible strains in logarithmic phase culture at a concentration of 10* cfu/mL. Antibiotics were added at concentrations one, two or four times the MIC. Viable counts were performed 0,2, 3, 5,7, and 24 h after addition of the antibiotic. The Table shows the MIC,,,, MIC*, and geometric mean MICs for the 83 strains tested in comparison with our previous results. It can be seen that all current MICs were two to ten times greater than before. Sparfloxadn was the most active fluorinated quinolone against these clinical isolates of Acinetobacter spp. with a MICM of 3 mg/L and a geometric mean MIC of 1-6 mg/L. The proportions of fully susceptible strains were 25%, 30%, 31% and 45% for pefloxacin, ciprofloxatin, temafloxacin and sparfloxadn respectively. The Figure shows the killing curves after exposure to antibiotics. A bactericidal effect was obtained within 3 h with sparfloxacin and 5 h with temafloxacin; ciprofloxacin and pefloxacin were bacteriostatic only. This increasing resistance might have resulted from the early introduction and largescale usage of pefloxacin in France. Multiply-resistant acinetobacter strains involved in nosocomial infections should respond to a combination of one of the new fluorinated quinolones with an aminoglycoside. M. L. JOLY-GUILLOU E. BERGOGNE-BEREZIN
Correspondence
References Centers for Disease Control (1987). Antibiotic-resistant strains of Neisserla gonorrhoeae: policy guidelines for detection, mnnagcment and control. Morbidity Mortality Weekly Report 36, Suppl. 5. 1-18. Centers for Disease Control (1990). Plasmid-mediated antimicrobial resistances in Neisserla gonorrhoeae. United States, 1988 and 1989. Morbidity Mortality Weekly Report 39, 284-93. Fuchs, P. C , Jones, R. N., Barry, A. L. & Thornsberry, C. (1986). Tentative disk diffusion susceptibility interpretive criteria for BMY-28142, a new cephalosporin. Journal of Clinical Microbiology 23, 634-6. Jones, R. N., Fuchs, P. C , Washington, J. A., II, Gavan, T. L., Murray, P. R., Geriach, E H. et al. (1990). Interpretive criteria, quality control guidelines, and drug stability studies for susceptibility testing of cefotaxime, cefoxitin, ceftazidime, and cefuroxime against Neisseria gonorrhoeae. Diagnostic Microbiology and Infectious Disease 13, 499-508. Jones, R. N., Gavan, T. L., Thornsberry, C , Fuchs, P. C , Geriach, E H., Knapp, J. S. et al (1989). Standardization of disk diffusion asd agar dilution susceptibility tests for Neisseria gonorrhoeae: interpretive criteria and quality control guidelines for ceflriaxone, penicillin, spectinomycin, and tetracyctine. Journal of Clinical Microbiology 21, 2756-66.
Kessler, R. E , Bies, M., Buck, R. E., Chishohn, D. R., Pursiano, T. A., Tsai, Y. H. et al. (1985). Comparison of a new cephalosporin, BMY 28142, with other broad-spectrum /Mactam antibiotics. Antimicrobial Agents and Chemotherapy TJ, 207-16. Khan, N. J., Bihi, J. A., Schell, R. F., LeFrock, J. L. & Weber, S. J. (1984). Antimicrobial activities of BMY-28142, cefbuperazone, and cefpiramide compared with those of other cephalospoiins. Antimicrobial Agents and Chemotherapy 26, 585-90. National Committee for Clinical Laboratory Standards (1989). Development of In vitro Susceptibility Testing Criteria and Quality Control Parameters. Tentative Guideline M23-T. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (1990a). Performance Standards for Antimlcrobk Disk Susceptibility Tests. Approved Standard M2-A4. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (19906). Standard Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically. Approved Standard M7-A2. National Committee for Clinical Laboratory Standards, Villanova, PA. National Committee for Clinical Laboratory Standards (1991). Information Supplement, M100-S3. National Committee for Clinical Laboratory Standards, Vulanova, PA. Ringertz, S., Rylander, M. & Kronvall (1991). Disk diffusion method for susceptibility testing of Neisseria gonorrhoeae. Journal of Clinical Microbiology 29, 1604-9.
In-ritro activity of sparfloxadn, pefloxadn, dprofloxadn and temafloxadn against clinical isolates of Acmetobmcter spp. Sir, Over the last ten years, Adnetobacter spp. have become an important cause of hospital acquired infections (Bergogne-Berezin & Jolly-Guillou, 1991). The most frequent infections are outbreaks of respiratory tract infections in ventilated patients, bacteraemia and nosocomial urinary tract infections (Smego, 1985; Vandenbroucke-Grauls et al., 1988). Nosocomial infections with Acinetobacter spp. constitute a difficult therapeutic problem due to a rapid increase in resistance to most newer /J-lactams and aminoglycosides. In 1985-86 a study of the susceptibility of 130 clinical isolates of acinetobacter strains showed very promising results with ciprofloxacin, ofloxacin and pefloxadn (Bergogne-Berezin &
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
liminary guidelines by the Centers for Disease Control (CDC, 1987). Those guidelines were necessary to deal with the documented increase in plasmid-mediated resistances to penicillins and tetracyclines (CDC, 1990). Currently the number of /Mactamase-stable cephalospoiins having NCCLS (1991) interpretive criteria for gonococcal testing includes ceflriaxone, cefotaxime, cefoxitin, ceftazidime, cefuroxime, cefotetan and cefixime. To this list we now add cefepime, a compound with documented high activity against N. gonorrhoeae strains equal to that of other so-called 'third-generation' cephalospoiins (Kessler el al., 1983; Fuchs et al., 1986). Acknowledgements. The following persons contributed significant technical or manuscript processing support to this study: Dr F. Koontz, M. Erwin, M. Barrett, B. Briggs, D. Johnson, and L. Miller. This investigation was made possible by technical grants from G.D. Searle and Co., Lederle Laboratories and Bristol-Myers Squibb. RONALD N. JONES Anti-Infecthes Research Center, Department of Pathology, 5232 RCP, University of Iowa College of Medicine, Iowa City, Iowa 52242 USA
Correspondence (b)
467 CO
^ r
(c)
^
Co
c /
/
.T
_^__
s
^
i
24
^
i
w
1/
1
1
24
24
3 6
Tlmt(h) Figure. Killing curves of Acmtobacter spp. in the presence of pefloxacin (t>)> ciprofloxacin ( Q , temafloxacin (T) and sparfloxacin (S) at one (a), two (b) or four (c) times MIC, compared to control (Co). Table. MICs of fluoroquinolones for Acinetobacter baumanii Compound
Year
Range of MIC« (mg/L)
MIC,,, (mg/L)
MIC, (mg/L)
Geometric mean MlC/(mg/L)
Pefloxacin
1985 1988-89 1990
0-25-16 0125-128 0125- > 128
1-05 141 46-3
6-7 7+6 196
1-6 102 24-3
Ciprofloxacin
1985 1988-89 1990
0016-32 0016-128 003-128
07 7-3 33-7
4-6 6O4 88
O98 5-7 12-5
Ofloxacin
1985 1988-89
006-16 0016-32
3-7 14-6
103 203
Temafloxacin
1988-89 1990
0016-64 003-128
2-8 14-3
41 49
2-8 6-3
Sparfloxacin
1990
003-32
3
7-6
1-6
Joly-Guillou, 1985). A few years later, after the introduction of these new quinolones another investigation was carried out with acinetobacter strains collected in 1988-1989 (Bergogne-Bcrezin & Joly-Guillou, 1989). It was noted that acinetobacter strains had become more resistant to these quinolones. We now report the activity of a new fluorinated quinolone, sparfloxacin, compared with that of
069 3-37
pefloxacin, ciprofloxacin and temafloxacin against acinetobacter strains collected in 1990. Two-fold dilutions of freshly prepared solutions of antimicrobial agents were incorporated into Mueller-Hinton agar to yield final concentrations ranging from 256 to 0-03 mg/L. An inoculum of approximately 106 cfu was applied with a Steers replicator and the plates incubated aerobically at 35°C
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
\
p
s
468
Correspondence
Department of Microbiology, University Hospital Bichat-Claude Bernard, 46 rue Henri-Huchard. 75877-Paris Cedex 18, France
References Bergogne-Berezin, E., Joly-Guillou, M. L. (1985). An underestimated nosocomial pathogen, Acinetobacter calcoaceticus. Journal of Antimicrobial Chemotherapy 16, 535-8. Bergogne-Berfczin, E. & Joly-Guillou, M. L. (1989). Activity of new fluoroquinolona against acinetobacter from nosocomial infection!. Quinolones Bulletin 5, 23-6. Bergogne-Bererin, E. & Joly-Guillou, M. L. (1991). Hospital infection with Acinetobacter spp.: an increasing problem. Journal of Hospital Infection 18,250-5. Smego, R. A. (1985). Endemic nojomial bacteremia. Archives of Internal Medicine 145, 2174-9. Vandenbroucke-Grauls, C. M. J. E., Kerver, A. J. H., Rommet, J. H. Jansen, R., Den Dekker, C. & Verhoef, J. (1988). Endemic Acinetobacter anitratus in a surgical intensive care unit mechanical ventilator! as a reservoir. European Journal of Clinical Microbiology and Infectious Disease 7, 485-9.
In-vttro activity of twefre antibiotics against clinical isolates of Biloptdla wadswortMa Sir, Bilophila wadsworthia is a newly described Gram-negative anaerobic bacillus which was first discovered in the late 1980s by Bennion et al. (1990) in specimens from gangrenous and perforated appendicitis. They found that this organism was the fourth most common anaerobic isolate from specimens obtained from the above patient group; it was also isolated from normal faecal samples. However, B. wadsworthia is a relatively slow-growing anaerobe that produces small, ill-defined colonies and requires a selective medium for its isolation; hence its only recent discovery. A more detailed study on the characterization of B. wadsworthia was carried out by Baron et al. (1989) who described it as strongly catalascpositive, urcase-positive and able to reduce nitrate; moreover, it was stimulated by bile. Previously, there has only been a brief comment on the antimicrobial susceptibility of B. wadsworthia (Bennion et al., 1990) with a more comprehensive report proposed to be reported elsewhere. This is most probably the first report on strains isolated in the United Kingdom. In this study we examined 42 fresh clinical isolates of B. wadsworthia from randomly collected faeces specimens submitted to the Royal Hallamshire Hospital, Sheffield for the investigation of enteric pathogens. Specimens were plated onto either Bacteroides ureolyticus medium (Lab M, Bury, UK) (Eley, Clarry & Bennett, 1989) or Aeromonas medium (Difco, Surrey, UK) and B. wadsworthia identified as described previously, using biochemical tests, API Rapid ID 32A and gas-liquid chromatography (Baron et al., 1989), with further confirmation by sodium dodecyl sulphate polyacrylamide gel dectrophoresis. For comparison we also tested ATCC strain 49260 and two strains isolated from the VA Wadsworth Medical Center, Los Angeles, USA (the original source). MIC determinations were made by an agar dilution method (Jones et al., 1985) using Brain Heart Infusion (BHI) agar supplemented with yeast extract (5 g/L), and containing doubling dilutions of the different antibiotics. Test organisms were grown anaerobically for four days. Growth was harvested and suspended in supplemented BHI broth (as above) to match Wellcome opacity tube no. 1 at a concentration of 109 cfu/mL and diluted 1 in 100. A multipoint inoculator was used to deliver a 1 /iL inoculum containing
Downloaded from http://jac.oxfordjournals.org/ at University of California, Santa Cruz on April 4, 2015
for 24 h. Kinetic killing curves were determined for susceptible strains in logarithmic phase culture at a concentration of 10* cfu/mL. Antibiotics were added at concentrations one, two or four times the MIC. Viable counts were performed 0,2, 3, 5,7, and 24 h after addition of the antibiotic. The Table shows the MIC,,,, MIC*, and geometric mean MICs for the 83 strains tested in comparison with our previous results. It can be seen that all current MICs were two to ten times greater than before. Sparfloxadn was the most active fluorinated quinolone against these clinical isolates of Acinetobacter spp. with a MICM of 3 mg/L and a geometric mean MIC of 1-6 mg/L. The proportions of fully susceptible strains were 25%, 30%, 31% and 45% for pefloxacin, ciprofloxatin, temafloxacin and sparfloxadn respectively. The Figure shows the killing curves after exposure to antibiotics. A bactericidal effect was obtained within 3 h with sparfloxacin and 5 h with temafloxacin; ciprofloxacin and pefloxacin were bacteriostatic only. This increasing resistance might have resulted from the early introduction and largescale usage of pefloxacin in France. Multiply-resistant acinetobacter strains involved in nosocomial infections should respond to a combination of one of the new fluorinated quinolones with an aminoglycoside. M. L. JOLY-GUILLOU E. BERGOGNE-BEREZIN
