THE JOURNAL OF INFECTIOUS DISEASES. VOL. 136, NO.5. NOVEMBER 1977
© 1977 by the University of Chicago. All rights reserved.
In Vitro Activity of Five Oral Cephalosporins against Anaerobic Pathogenic Bacteria S. Shadomy,
c. G. Mayhall,
From the Division of Infectious Diseases, Department of Medicine, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia
and Elaine Apollo
Cefaclor (3-chloro-7-D-[2-phenyI-glycemanido]-3cepham-4-carboxylic acid) is a semisynthetic broad-spectrum cephalosporin antibiotic active against both gram-negative and gram-positive bacteria [I]. Metabolic studies in animals have shown that this drug is readily absorbed intact from the gastrointestinal tract [2]. Cefatrizine (7-[D-a-amino-a- (hydroxylphenyl)acetamido]-3- (1 H,2,3-triazol-5-yl) thio]methyl]-3-cephem-4-carboxylic acid) is another semisynthetic cephalosporin with a similar spectrum of activity and also is absorbed from the gastrointestinal tract of rodents [3, 4]. The purpose of this study was to compare the in vitro activities of these two new orally absorbed cephalosporins with those of other orally absorbed cephalosporins against clinical isolates of anaerobic pathogenic bacteria. The other oral cephalosporins studied, now in clinical use, included cephalexin, cephaloglycin, and cephadrine. Because of its previously demonstrated activity against certain anaerobes [5], cefoxitin, a parenteral cephamycin antibiotic, was included for comparison.
from human clinical materials and supplied by the Clinical Laboratories, Medical College of Virginia Hospitals (Richmond, Va.). The remaining organisms were obtained from the American Type Culture Collection, Rockville, Md., the Anaerobe Laboratory, Virginia Polytechnic Institute and State University, Blacksburg, Va., and the Wilmington Medical Center, Wilmington, Del. A total of 44 isolates were tested. These included 17 isolates of Bacteroides fragilis, five isolates of Bacteroides species other than B. fragilis, seven isolates of Clostridium species, 11 isolates of Peptococcus species, three isolates of Propionibacterium species, and one isolate of Fusobacterium species. Antibiotics. Cefaclor (compound no. 99638, lot no. SI-100-6C, activity of 961 fLgjmg), cephaloglycin (lot no. 9NK09, activity of 890 fLgjmg), and cephalexin monohydrate (lot no. S1-89-6B, activity of 940 fLg/mg) were obtained from Lilly Research Laboratories, Indianapolis, Ind. Cefatrizine (BL-S640PG, lot no. 75-F396, activity of 868 fLgjmg) was obtained from Bristol Laboratories (Syracuse, N. Y.), and cephadrine monohydrate (batch no. NN083NE, activity of 967 fLgfmg) was obtained from the Squibb Institute for Medical Research, New Brunswick, N.J. Cefoxitin sodium (lot no. C-D938, activity of 949 fLgf mg) was supplied by Merck Sharp and Dohme, West Point, Pa. Solutions of cefatrizine, cephadrine, cephaloglycin, and cefoxitin were prepared in sterile distilled water. Cefaclor was dissolved in 0.1 M Sorenson's buffer, pH 4.5, and cephalex-
Materials and Methods
Bacteria. Most of the isolates of anaerobic bacteria included in this study were recovered Received for publication May 5,1977. These studies were supported in part by a grant from Lilly Research Laboratories. Please address requests for reprints to Dr. S. Shadomy, Box 85, Mev Station, Richmond, Virginia 23298.
697
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
The in vitro inhibitory activities of cefaclor and cefatrizine, two new orally absorbed cephalosporin antibiotics, against 44 isolates of anaerobic pathogenic bacteria were measured using the agar dilution procedure of the World Health OrganizationInternational Collaborative Study. Tests also were performed with cephalexin, cephaloglycin, and cephadrine, as well as with the parenteral cephamycin antibiotic cefoxitin. Cefoxitin was the most active antibiotic and inhibited the majority of isolates at a concentration of ::=:'4 ~/ml. None of the oral cephalosporins was clearly superior against all of the anaerobic isolates; only cephadrine and cefatrizine appeared to have any potential clinical value.
698
Results and Discussion
Results obtained with the six antibiotics and 43 isolates of anaerobic pathogenic bacteria are presented in table I. In nearly all instances, cefoxi tin was the most active antibiotic in vitro; in the only exception cephadrine was the most active antibiotic against five isolates of Bacteroides melaninogenicus and Bacteroides corrodens. Not shown are data for one isolate of Fusobacterium species that was susceptible to cefoxitin (MIC, 4 JLgjml), cephadrine (MIC, 16 JLgjml), and cefatrizine (MIC, 64 JLgjml) but resistant to cefaclor, cephalexin, and cephaloglycin (MIC, ~128 JLgjml). Cefoxitin was the only antibiotic with clinically significant activity against B. fragilis, with in-
hibition of 82% of isolates tested at a concentration of 16 JLgjml, while cephadrine was the second most active, with inhibition of 77% at 32 /Lgjml, which is probably the maximal chemotherapeutically significant concentration for these compounds and microorganisms as suggested by Sutter and Finegold [7]. Cephaloglycin, cephalexin, cefatrizine, and cefaclor were weakly to poorly active at ~32 /LgjmI. As already noted, cephadrine was the most active antibiotic against five isolates of Bacteroides species other than B. fragilis, with inhibition of 100% of isolates tested at 8 /LgjmI. Both cephalexin and cefoxitin were similarly active at 8 /Lgjml but not at lower concentrations. Cefaclor was only slightly less active with inhibition of 100% at 16 /Lgjml, while cefatrizine and cephaloglycin were the least active. Cefoxitin was by far the most active antibiotic against Clostridium species, with inhibition of all seven isolates tested at 2 /LgjmI. Cefatrizine and cephadrine, the next most active compounds, each were inhibitory for three of the seven isolates at the same concentration. The least most active drug was cephaloglycin, which was subinhibitory at 2 /Lg/ml and inhibitory for only two isolates at 4 /LgjmI. The remaining compounds were inhibitory for all isolates at 16 /Lgj mI. Cefoxitin was the most active antibiotic against II isolates of Peptococcus species, with inhibition of all isolates at 4 /LgjmI. Cefaclor and cefatrizine were the next most active, with inhibition of 50% and 56%, respectively, of isolates tested at 8 /Lgjml. Cephaloglycin was the least most active, with inhibition of only 36% at 16 /Lg/mI. Only three isolates of Propionibacterium species were tested. Thus, it was difficult to evaluate results for this genus. However, all three were highly susceptible to cefacIor, cephalexin, cephadrine, and cefoxitin at concentrations of ~2 /Lgj mI. The same concentration of cefatrizine was inhibitory for only one of the three isolates; 2 JLg of cephaloglycinjml was subinhibitory for all three isolates. The results presented here are in excellent agreement with previously published results of in vitro studies with cephalosporins or related drugs and anaerobic bacteria. Sutter and Fine-
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
in was dissolved in 1.0% Sorenson's buffer, pH 6.0. All solutions were sterilized by filtration. Antimicrobial susceptibility tests. A modification of the agar dilution procedure of the World Health Organization-International Collaborative Study was used [6]. Inocula were prepared from freshly inoculated cultures grown in thioglycollate medium (Baltimore Biological Laboratories [BBL], Baltimore, Md.) supplemented with hemin (5 JLg/ml) and vitamin Ks (0.5 JLgjml). The thioglycollate cultures, with caps loose, were incubated in a GasPak jar (BBL, GasPak 100,@ Anaerobic Systems, Becton-Dickinson Co., Rutherford, N. J.) at 37 C for 3-4 hr. The cultures were adjusted to the turbidity of a no. I McFarland nephalometer standard with fresh brucella broth (BBL) and then inoculated, using a mechanical replicator (Melrose Machine Shop, Woodlyn, Pa.), onto freshly prepared brucella agar plates containing graded concentrations of the test antibiotics and supplemented with 5% laked sheep's blood, vitamin K s (0.5 JLgjml), and added agar (final concentration, 2.5%). Concentrations of drug ranged from 128 to 0.063 JLgjmI. Growth control plates without antibiotic were inoculated both before and after inoculation of each series of drug dilutions. Test cultures were incubated for 48 hr in GasPak jars (BBL) at 37 C. The MIC was defined as the lowest concentration of antibiotic permitting no growth, a barely visible haze, and j or one or two discreet colonies. All tests were done in duplicate.
Shadomy, Mayhall, and Apollo
Comparison of Five Oral Cephalosporins
699
Table 1. In vitro inhibitory activities of five oral cephalosporins and cefoxitin against 43 isolates of anaerobic pathogenic bacteria as determined by the agar dilution test.
Species (no. of isolates tested), antibiotic
Cumulative percentages of isolates inhibited at indicated concentration (~g/ml) of antibiotic *
0.25 0.5
2
81.7 78.5 42.6 30.7
4
8
20 20
3.03
20
20 20 20 20
20 20 20 20 20
20 20 20 20 20 20
2.97
12
29 18
41
47
100 100 100 100 100
6 6
18 12
24 18
6
6
12
77
40 20 20 60 20 40
60 60 60 80 20 80
80 60 60 80 40 80
80 80 100
14
29
43
43 71 86 86 29
4.88
3.62 8.72 0.61
29
57
4.29
20
30
40
22
33
27 20
36
9
9
18
27
43
18 20 18
18
1.0 5.04
0.79
~128
6
5.94
2.79 7.51 7.46 19.3 0.64
64
82
41 77 6 94
100
100 80
80
100
60 100
60
100
86 100 86 86 71
100 100 100 100
50 56 36 40 36
70 100 46 40 36
6
9.4
1.00 6.06 1.74
32
6
113
1.52 4.60
16
0.40
67 33 100
5.04 0.31
67 100
86
6
100
100
44 36
18 91
33 36 30 27 91
36 100
100 33 67
33
67
100
30
71
88
30
67
100 73 100 36
100
64
100
100 100
*Percentages were rounded to the nearest whole number. tIncluding two isolates of Bacteroides corrodens and three of Bacteroides melaninogenicus, tSome data were excluded because of contamination.
gold [7] reported results similar to ours for cefoxitin, as did Talley et al. [8] for both cefoxitin and cephalexin. All of these data clearly indicate probable clinical efficacy for cefoxitin in the treatment of serious anaerobic infections. However, a similar prediction for probable clinical efficacy is difficult to make for any of the oral cephalosporins evaluated in this study. If one accepts the suggestion of Sutter and Finegold that 32 p.g/ml represents the upper limit of clinically significant concentrations, then, clearly, none of
the oral cephalosporins with the possible exception of cephadrine has a potential role in treatment of serious, life-threatening infections caused by B. fragilis, although both cephalexin and cephadrine might be efficaceous in treatment of other less severe infections with Bacteroides. Similarly, with the possible exception of cefatrizine, none of the oral cephalosporins appears to have any potential value for treatment of infections caused by Peptococcus species. In contrast, both cefatrizine and cephadrine and, possibly,
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
Bae teroides fragilis (17) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Bacteroides species (5)t Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Clostridium species (7) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Pep tocoeeus species (11) t Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Propionibacterium species (3) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin
Geometric mean MIC ~0.06 0.13
700
cefaclor and cephalexin may have a potential role in treatment of less serious skin and soft tissue infections caused by Clostridium species.
Shadomy, Mayhall, and Apollo
4.
5. References
6.
7.
8.
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
1. Bill, N. J., Washington, J. A. II. Comparison of in vitro activity of cephalexin, cephadrine and cefaclor. Antimicrob. Agents Chemother. 11:470-474,1977. 2. Sullivan, H. R., Due, S. L., Kau, D. L. K., Quay, J. F., Miller, W. Metabolism of [14C] cefaclor, a cephalosporin antibiotic, in three species of laboratory animals. Antimicrob. Agents Chemother. 10:630-638, 1976. 3. Actor, P., Uri, J. V., PhiJIips, L., Sachs, C. S., Guarini, J. R., Zajac, I., Berges, D. A., Dunn, G. L., Hoover, J. R. E., Weisbach, J. A. Laboratory studies with cefatrizine (SK&F 6077]): a new broad-spectrum
orally-active cephalosporin. J. Antibiot. 28:594-601, 1975. Leitner, F., Buck, R. E., Misiek, M., Pursiano, T. A., Price. K. E. BL-S640, a cephalosporin with a broad spectrum of antibacterial activity: properties in vitro. Antimicrob. Agents Chemother. 7:298-305, 1975. Hamilton-MiJler, J. M. T., Kerry, D. W., Brumfitt, W. An in vitro comparison of cefoxitin, a semi-synthetic cephamycin, with cephalothin. J. Antibiot. 27:42-48, 1974. Ericsson, H. M., Sherris, J. C. Antibiotic sensitivity testing. Report of an international collaborative study. Acta Pathol. Microbiol. Scand [B] Suppl. 217:1-90, 1971. Sutter, V. L., Finegold, S. M. Susceptibility of anaerobic bacteria to carbenicillin, cefoxitin and related drugs. J. Infect. Dis. 131:417-422, 1975. Talley, F. P., Jacobus, N. V., Bartlett, J. G., Gorbach, S. L. Susceptibility of anaerobes to cefoxitin and other cephalosporins. Antimicrob. Agents Chemother. 7: 128-132, 1975.
© 1977 by the University of Chicago. All rights reserved.
In Vitro Activity of Five Oral Cephalosporins against Anaerobic Pathogenic Bacteria S. Shadomy,
c. G. Mayhall,
From the Division of Infectious Diseases, Department of Medicine, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia
and Elaine Apollo
Cefaclor (3-chloro-7-D-[2-phenyI-glycemanido]-3cepham-4-carboxylic acid) is a semisynthetic broad-spectrum cephalosporin antibiotic active against both gram-negative and gram-positive bacteria [I]. Metabolic studies in animals have shown that this drug is readily absorbed intact from the gastrointestinal tract [2]. Cefatrizine (7-[D-a-amino-a- (hydroxylphenyl)acetamido]-3- (1 H,2,3-triazol-5-yl) thio]methyl]-3-cephem-4-carboxylic acid) is another semisynthetic cephalosporin with a similar spectrum of activity and also is absorbed from the gastrointestinal tract of rodents [3, 4]. The purpose of this study was to compare the in vitro activities of these two new orally absorbed cephalosporins with those of other orally absorbed cephalosporins against clinical isolates of anaerobic pathogenic bacteria. The other oral cephalosporins studied, now in clinical use, included cephalexin, cephaloglycin, and cephadrine. Because of its previously demonstrated activity against certain anaerobes [5], cefoxitin, a parenteral cephamycin antibiotic, was included for comparison.
from human clinical materials and supplied by the Clinical Laboratories, Medical College of Virginia Hospitals (Richmond, Va.). The remaining organisms were obtained from the American Type Culture Collection, Rockville, Md., the Anaerobe Laboratory, Virginia Polytechnic Institute and State University, Blacksburg, Va., and the Wilmington Medical Center, Wilmington, Del. A total of 44 isolates were tested. These included 17 isolates of Bacteroides fragilis, five isolates of Bacteroides species other than B. fragilis, seven isolates of Clostridium species, 11 isolates of Peptococcus species, three isolates of Propionibacterium species, and one isolate of Fusobacterium species. Antibiotics. Cefaclor (compound no. 99638, lot no. SI-100-6C, activity of 961 fLgjmg), cephaloglycin (lot no. 9NK09, activity of 890 fLgjmg), and cephalexin monohydrate (lot no. S1-89-6B, activity of 940 fLg/mg) were obtained from Lilly Research Laboratories, Indianapolis, Ind. Cefatrizine (BL-S640PG, lot no. 75-F396, activity of 868 fLgjmg) was obtained from Bristol Laboratories (Syracuse, N. Y.), and cephadrine monohydrate (batch no. NN083NE, activity of 967 fLgfmg) was obtained from the Squibb Institute for Medical Research, New Brunswick, N.J. Cefoxitin sodium (lot no. C-D938, activity of 949 fLgf mg) was supplied by Merck Sharp and Dohme, West Point, Pa. Solutions of cefatrizine, cephadrine, cephaloglycin, and cefoxitin were prepared in sterile distilled water. Cefaclor was dissolved in 0.1 M Sorenson's buffer, pH 4.5, and cephalex-
Materials and Methods
Bacteria. Most of the isolates of anaerobic bacteria included in this study were recovered Received for publication May 5,1977. These studies were supported in part by a grant from Lilly Research Laboratories. Please address requests for reprints to Dr. S. Shadomy, Box 85, Mev Station, Richmond, Virginia 23298.
697
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
The in vitro inhibitory activities of cefaclor and cefatrizine, two new orally absorbed cephalosporin antibiotics, against 44 isolates of anaerobic pathogenic bacteria were measured using the agar dilution procedure of the World Health OrganizationInternational Collaborative Study. Tests also were performed with cephalexin, cephaloglycin, and cephadrine, as well as with the parenteral cephamycin antibiotic cefoxitin. Cefoxitin was the most active antibiotic and inhibited the majority of isolates at a concentration of ::=:'4 ~/ml. None of the oral cephalosporins was clearly superior against all of the anaerobic isolates; only cephadrine and cefatrizine appeared to have any potential clinical value.
698
Results and Discussion
Results obtained with the six antibiotics and 43 isolates of anaerobic pathogenic bacteria are presented in table I. In nearly all instances, cefoxi tin was the most active antibiotic in vitro; in the only exception cephadrine was the most active antibiotic against five isolates of Bacteroides melaninogenicus and Bacteroides corrodens. Not shown are data for one isolate of Fusobacterium species that was susceptible to cefoxitin (MIC, 4 JLgjml), cephadrine (MIC, 16 JLgjml), and cefatrizine (MIC, 64 JLgjml) but resistant to cefaclor, cephalexin, and cephaloglycin (MIC, ~128 JLgjml). Cefoxitin was the only antibiotic with clinically significant activity against B. fragilis, with in-
hibition of 82% of isolates tested at a concentration of 16 JLgjml, while cephadrine was the second most active, with inhibition of 77% at 32 /Lgjml, which is probably the maximal chemotherapeutically significant concentration for these compounds and microorganisms as suggested by Sutter and Finegold [7]. Cephaloglycin, cephalexin, cefatrizine, and cefaclor were weakly to poorly active at ~32 /LgjmI. As already noted, cephadrine was the most active antibiotic against five isolates of Bacteroides species other than B. fragilis, with inhibition of 100% of isolates tested at 8 /LgjmI. Both cephalexin and cefoxitin were similarly active at 8 /Lgjml but not at lower concentrations. Cefaclor was only slightly less active with inhibition of 100% at 16 /Lgjml, while cefatrizine and cephaloglycin were the least active. Cefoxitin was by far the most active antibiotic against Clostridium species, with inhibition of all seven isolates tested at 2 /LgjmI. Cefatrizine and cephadrine, the next most active compounds, each were inhibitory for three of the seven isolates at the same concentration. The least most active drug was cephaloglycin, which was subinhibitory at 2 /Lg/ml and inhibitory for only two isolates at 4 /LgjmI. The remaining compounds were inhibitory for all isolates at 16 /Lgj mI. Cefoxitin was the most active antibiotic against II isolates of Peptococcus species, with inhibition of all isolates at 4 /LgjmI. Cefaclor and cefatrizine were the next most active, with inhibition of 50% and 56%, respectively, of isolates tested at 8 /Lgjml. Cephaloglycin was the least most active, with inhibition of only 36% at 16 /Lg/mI. Only three isolates of Propionibacterium species were tested. Thus, it was difficult to evaluate results for this genus. However, all three were highly susceptible to cefacIor, cephalexin, cephadrine, and cefoxitin at concentrations of ~2 /Lgj mI. The same concentration of cefatrizine was inhibitory for only one of the three isolates; 2 JLg of cephaloglycinjml was subinhibitory for all three isolates. The results presented here are in excellent agreement with previously published results of in vitro studies with cephalosporins or related drugs and anaerobic bacteria. Sutter and Fine-
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
in was dissolved in 1.0% Sorenson's buffer, pH 6.0. All solutions were sterilized by filtration. Antimicrobial susceptibility tests. A modification of the agar dilution procedure of the World Health Organization-International Collaborative Study was used [6]. Inocula were prepared from freshly inoculated cultures grown in thioglycollate medium (Baltimore Biological Laboratories [BBL], Baltimore, Md.) supplemented with hemin (5 JLg/ml) and vitamin Ks (0.5 JLgjml). The thioglycollate cultures, with caps loose, were incubated in a GasPak jar (BBL, GasPak 100,@ Anaerobic Systems, Becton-Dickinson Co., Rutherford, N. J.) at 37 C for 3-4 hr. The cultures were adjusted to the turbidity of a no. I McFarland nephalometer standard with fresh brucella broth (BBL) and then inoculated, using a mechanical replicator (Melrose Machine Shop, Woodlyn, Pa.), onto freshly prepared brucella agar plates containing graded concentrations of the test antibiotics and supplemented with 5% laked sheep's blood, vitamin K s (0.5 JLgjml), and added agar (final concentration, 2.5%). Concentrations of drug ranged from 128 to 0.063 JLgjmI. Growth control plates without antibiotic were inoculated both before and after inoculation of each series of drug dilutions. Test cultures were incubated for 48 hr in GasPak jars (BBL) at 37 C. The MIC was defined as the lowest concentration of antibiotic permitting no growth, a barely visible haze, and j or one or two discreet colonies. All tests were done in duplicate.
Shadomy, Mayhall, and Apollo
Comparison of Five Oral Cephalosporins
699
Table 1. In vitro inhibitory activities of five oral cephalosporins and cefoxitin against 43 isolates of anaerobic pathogenic bacteria as determined by the agar dilution test.
Species (no. of isolates tested), antibiotic
Cumulative percentages of isolates inhibited at indicated concentration (~g/ml) of antibiotic *
0.25 0.5
2
81.7 78.5 42.6 30.7
4
8
20 20
3.03
20
20 20 20 20
20 20 20 20 20
20 20 20 20 20 20
2.97
12
29 18
41
47
100 100 100 100 100
6 6
18 12
24 18
6
6
12
77
40 20 20 60 20 40
60 60 60 80 20 80
80 60 60 80 40 80
80 80 100
14
29
43
43 71 86 86 29
4.88
3.62 8.72 0.61
29
57
4.29
20
30
40
22
33
27 20
36
9
9
18
27
43
18 20 18
18
1.0 5.04
0.79
~128
6
5.94
2.79 7.51 7.46 19.3 0.64
64
82
41 77 6 94
100
100 80
80
100
60 100
60
100
86 100 86 86 71
100 100 100 100
50 56 36 40 36
70 100 46 40 36
6
9.4
1.00 6.06 1.74
32
6
113
1.52 4.60
16
0.40
67 33 100
5.04 0.31
67 100
86
6
100
100
44 36
18 91
33 36 30 27 91
36 100
100 33 67
33
67
100
30
71
88
30
67
100 73 100 36
100
64
100
100 100
*Percentages were rounded to the nearest whole number. tIncluding two isolates of Bacteroides corrodens and three of Bacteroides melaninogenicus, tSome data were excluded because of contamination.
gold [7] reported results similar to ours for cefoxitin, as did Talley et al. [8] for both cefoxitin and cephalexin. All of these data clearly indicate probable clinical efficacy for cefoxitin in the treatment of serious anaerobic infections. However, a similar prediction for probable clinical efficacy is difficult to make for any of the oral cephalosporins evaluated in this study. If one accepts the suggestion of Sutter and Finegold that 32 p.g/ml represents the upper limit of clinically significant concentrations, then, clearly, none of
the oral cephalosporins with the possible exception of cephadrine has a potential role in treatment of serious, life-threatening infections caused by B. fragilis, although both cephalexin and cephadrine might be efficaceous in treatment of other less severe infections with Bacteroides. Similarly, with the possible exception of cefatrizine, none of the oral cephalosporins appears to have any potential value for treatment of infections caused by Peptococcus species. In contrast, both cefatrizine and cephadrine and, possibly,
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
Bae teroides fragilis (17) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Bacteroides species (5)t Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Clostridium species (7) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Pep tocoeeus species (11) t Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin Propionibacterium species (3) Cefaclor Cefatrizine Cephalexin Cephadrine Cephaloglycin Cefoxitin
Geometric mean MIC ~0.06 0.13
700
cefaclor and cephalexin may have a potential role in treatment of less serious skin and soft tissue infections caused by Clostridium species.
Shadomy, Mayhall, and Apollo
4.
5. References
6.
7.
8.
Downloaded from http://jid.oxfordjournals.org/ at Indiana University Library on July 15, 2015
1. Bill, N. J., Washington, J. A. II. Comparison of in vitro activity of cephalexin, cephadrine and cefaclor. Antimicrob. Agents Chemother. 11:470-474,1977. 2. Sullivan, H. R., Due, S. L., Kau, D. L. K., Quay, J. F., Miller, W. Metabolism of [14C] cefaclor, a cephalosporin antibiotic, in three species of laboratory animals. Antimicrob. Agents Chemother. 10:630-638, 1976. 3. Actor, P., Uri, J. V., PhiJIips, L., Sachs, C. S., Guarini, J. R., Zajac, I., Berges, D. A., Dunn, G. L., Hoover, J. R. E., Weisbach, J. A. Laboratory studies with cefatrizine (SK&F 6077]): a new broad-spectrum
orally-active cephalosporin. J. Antibiot. 28:594-601, 1975. Leitner, F., Buck, R. E., Misiek, M., Pursiano, T. A., Price. K. E. BL-S640, a cephalosporin with a broad spectrum of antibacterial activity: properties in vitro. Antimicrob. Agents Chemother. 7:298-305, 1975. Hamilton-MiJler, J. M. T., Kerry, D. W., Brumfitt, W. An in vitro comparison of cefoxitin, a semi-synthetic cephamycin, with cephalothin. J. Antibiot. 27:42-48, 1974. Ericsson, H. M., Sherris, J. C. Antibiotic sensitivity testing. Report of an international collaborative study. Acta Pathol. Microbiol. Scand [B] Suppl. 217:1-90, 1971. Sutter, V. L., Finegold, S. M. Susceptibility of anaerobic bacteria to carbenicillin, cefoxitin and related drugs. J. Infect. Dis. 131:417-422, 1975. Talley, F. P., Jacobus, N. V., Bartlett, J. G., Gorbach, S. L. Susceptibility of anaerobes to cefoxitin and other cephalosporins. Antimicrob. Agents Chemother. 7: 128-132, 1975.
