Correspondence
Infectious Disease Division, Department of Internal Medicine University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, U.S.A. References Ericsson, H. M., Sherris, J. C. Antibiotic sensitivity testing: report of an international collaborative study. Ada Pathologica et Microbiologica Scandinavica Section B 217 (Suppl.): 1-90 (1971).
Miller, G. H., Arcieri, G., Weinstein, M. J. & Waitz, J. A. Biological activity of netilmicin, a broad-spectrum semisynthetic aminoglycoside antibiotic. Antimicrobial Agents and Chemo-
therapy 10: 827-36 (1976). Steers, E., Foltz, E. L. & Graves, B. S. An inocula replicating apparatus for routine testing of bacterial susceptibility to antibiotics. Antibiotic Chemotherapy 9: 307-11 (1959). Waitz, J. A., Miller, G. H., Moss, E., Jr & Chiu, P. J. S. Chemotherapeutic evaluation of 5-episissomicin (Sch22591), a new semi synthetic aminoglycoside.
Antimicrobial
Chemotherapy 13: 41-8 (1978).
Agents
and
Watanakunakorn, C. Comparative in vitro activity of Sen 20656, netilmicin, gentamicin, and
tobramycin. Antimicrobial Agents and Chemotherapy 10: 382-3 (1976). A comparison of the in vitro activity of rosamkln, erythromycln, spiramycln, penicillin and tetracycline against N. gonorrhoeae, including 0-lactamase producing isolates Sir, The recent emergence of penicillinase-producing isolates of Neisseria gonorrhoeae coupled with their tendency to higher minimum inhibitory concentrations (MICs) for tetracycline and erythromycin (Siegal et al., 1978) has given impetus to the search for new antimicrobials with increased activity against [J-lactamase producing isolates as well as against isolates with reduced sensitivity to penicillin. Rosamicin, a new macrolide antibiotic isolated from Micromonospora rosaria (Wagman et al., 1972) was shown to have increased activity against Gram-negative micro-organisms (Waitz, Drube, Moss & Weinstein, 1972; Crowe & Sanders, 1974), certain anaerobes (Santoro, Kaye & Levison, 1976; Sutter & Fine gold, 1976) and certain coccidial infections (Panitz, 1974) as compared to erythromycin or other macrolide antibiotics. In addition, a recent report, with 50 isolates of N. gonorrhoeae, suggested that rosamicin was very active against this species (Sanders & Sanders, 1977). The present study was undertaken to expand the published data base for N. gonorrhoeae and to compare the activity of rosamicin with penicillin and tetracycline, as well as with the macrolide antibiotics erythromycin and spiramycin. A total of 517 non-penicillinase-producing and 13 peniciUinase-producing N. gonorrhoeae isolates were tested. The penicillinase producing isolates had been sent to the National Neisseria Reference Centre, Laboratory Centre for Disease Control, during the period December 1976 to January 1978. (J-Lactamase positive isolates were tested for the production of penicillinase using the chromogenic cephalosporin nitrocefin (O'Callaghan, Morris Kirby & Shingler, 1972). The other isolates were collected for an antibiotic susceptibility survey in Canada (Dillon, Eidus & Diena, 1978) during the period 1973 to 1974. Prior to testing, all isolates had been stored at -70°C in heart infusion broth (Difco) containing 20% glycerol. In addition, WHO strains HI, V and VII, with different susceptibilities to penicillin, served as control strains
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
enzymes APH (30-1 and n , mediating resistance to neomycin and kanamycin; (2) adcnylating enzyme ANT (2"), mediating resistance to gentamicin and tobramycin; (3) adenylating enzyme ANT (40, mediating resistance to tobramycin and amikacin; (4) acetylating enzyme AAC (20, mediating resistance to gentamicin and tobramycin; (5) acetylating enzyme AAC (3)-I, mediating resistance to gentamicin. 5-episissomicin was not active against resistant strains that possessed the following aminoglycoside inactivating enzymes: (1) acetylating enzyme AAC (3)-II, mediating resistance to gentamicin and tobramycin; and (2) acetylating enzyme AAC (60, mediating resistance to tobramycin and amikacin (Waitz et al., 1978). 5-episissomicin was apparently not highly active against strains that were resistant to all aminoglycosides due to a decreased permeability to aminoglycosides, but 5-episissomicin was among the most active aminoglycosides against this type of resistant strain (Waitz et al., 1978). 5-episissomicin appears to be a promising new semi-synthetic aminocyclitol aminoglycoside and may be valuable when the currently available aminoglycosides lose their activity against a large number of Gram-negative bacilli. Whether 5-episissomicin will be used clinically in the future, will depend on results of extensive toxicologic, pharmacologic and animal studies, and eventually controlled comparative clinical trials. C. WATANAKUNAKORN
477
17.2
22.8
13.5
0.01 0.013 32.3 2.7 3.9 46.8
41.2 20.7 13.3 62.9
0.025 0.05 47.6 56.3 25.7 90.9
0.1 64.4 74.1 66.7 98.1
025 69.8 97.1 91.5 99.8 2.1
0.5 94.8 98.5 98.1 100 83
1.0
25.3
100 98.8 100
2.0
0.03
0.1
7.7 30.8 30-8 38-5 46-2
0003 0.005 0.013 0.025
100
0.25 53.8 38.5
0.5
30.8
76.7 92.3
1.0 100 100
2.0
38.5
4.0
77.0
8.0
Cumulative % inhibition for MIC* of:
7.7
10.0
8.0
66.3 87.8
100
4.0
84.6
16.0
Table 11. MICs of 13 B-lactamase-producingN. gonorrhoeae isolates
*All MICs expressed as pglml except for penicillin and spiramycin which are expressed as units/ml.
Penicillin Tetracycline Erythromycin Rosamicin Spiramycin
Antibiotic
0.2
0003 0.005
Cumulative % inhibition for MIC* of:
99.8
16.0
100
20.0 24.0 32.0
*All MICs expressed as pg/ml except for penicillin and spiramycin which are expressed as unitslml.
Penicillin Tetracycline Erythromycin Rosamicin Spiramycin
Antibiotic
15.4
40.0
20.0
Table I. MICs of 517 isolates of N. gonorrhoeae to rosamicin, erythromycin, spiramycin, penicillin and tetracycline
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
100
>40
24.0
64
100
32.0
Correspondence
were inhibited by this concentration (Table II). Similarly, 62-9 % of the P-lactamase minus strains were inhibited by 0-05(ig /ml rosamicin as compared to 38-5% of the P-lactamase positive isolates. The effect of rosamicin in inhibiting N. gonorrhoeae isolates has been previously investigated with only 50 strains (Sanders & Sanders, 1977). In this study we havetested 530 strains including 13 isolates that are 3lactamase positive. Rosamicin was more active than penicillin, erythromycin, tetracycline or spiramycin in inhibiting these isolates. Pharmacological studies (Waitz et al., 1972) have indicated that rosamicin has similar intraperitoneal, but greater subcutaneous and oral toxicity than erythromycin. However, rosamicin also appears to be better absorbed (Waitz et al., 1972). Recent studies indicate that rosamicin was highly concentrated in human prostatic secretions (Baumueller, 1977) and was present in high concentration in urethral and vaginal secretions of dogs (Hoyme et at., 1977). Because rosamicin is concentrated in vaginal, urethral and prostatic secretions, and in view of its significant activity against isolates of N. gonorrhoeae, further pharmacological studies concerning human toxicity and serum levels are essential. Acknowledgements We wish to thank the Disease Statistics and Operational Planning Section, Laboratory Center for Disease Control, and Mr Y. Mao for their co-operation in computer processing the data. The technical assistance of Mr Peter Lomax is gratefully acknowledged. We also wish to thank Dr B. B. Diena for his critical reading of the manuscript. J. R. DILLON P. D. DUCK L. EIDUS Antimicrobials Section, National Neisseria Reference Centre, Bureau of Bacteriology, Laboratory Centre for Disease Control, Tunney's Pasture, Ottawa, Ontario K1A OL2, Canada References Baumueller, A., Hoyme, U. & Madsen, P. O. Rosamicin—a new drug for the treatment of bacterial prostatitis. Antimicrobial Agents and Chemotherapy 12: 240-2 (1977). Crowe, C. C. & Sanders, Jr, W. E. Rosamitinevaluation in vitro and comparison with erythromycin and lincomycin. Antimicrobial Agents and Chemotherapy 5: 272-5 (1974).
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
for penicillin MICs. These strains were kindly supplied by Dr A. Reyn of the Statens Seruminstitut, Copenhagen. All isolates were subcultured on GC medium base (Difco) containing 1 % v/v of Kellogg's defined supplement (Kellogg, Peacock, Deacon, Brown & Pirkle, 1963). Inoculated plates were incubated for 18 h at 35° in an atmosphere of 5% COi. Agar dilution antibiotic susceptibility testing was carried out using a modified Steer's replicator method (Maier, Warner, Zubryzski & Child, 1977). Antibiotic-containing media were prepared in 400 ml volumes of GC medium base (Difco) to give the following final concentrations: rosamicin (Schering Corporation) 1-0, 0-5, 0-25, 0 1 , 0-05, 0025, 0-010 and 0-005 ng/ml; erythromycin (Sigma) 4-0, 2-0,1-0,0-5,0-25,0-1,0-05 and 0-25 ug/ml; penicillin (Ayerst) 40-0, 20-0, 10-0, 5-0, 2-0, 1-0, 0-5, 0-25, 0-1, 005, 0025 and 0-013 units/ml; spiramycin (Poulence) 640, 32-0, 160, 8-0, 4-0, 20, 1-0 and 0-5 units/ml; and tetracycline HC1 (Bristol Laboratories) 4-0, 2-0, 10, 0-5, 0-25, 0 1 , 0-05, 0-25, 0 1 , 0-05 and 0-025 ug/ml. The minimum inhibitory concentration (MIC) was considered to be that concentration that completely inhibited growth. End points with 1 to 9 colonies were also considered sensitive. The results in Table I, with 517 isolates of N. gonorrhoeae, indicate that rosamicin was considerably more active than penicillin, tetracycline or the macrolide antibiotics erythromycin and spiramycin. Tetracycline and erythromycin concentrations of 0-05 Ug/ml inhibited under 20% of the isolates, while 62-9% and 41-2% of the strains were inhibited by rosamicin and penicillin, respectively. An even greater demarcation in activity is evident at concentrations of 0-1 ug/ml (or units in the case of penicillin). Rosamicin inhibited 90-9 % of the isolates while the other antibiotics inhibited from 25-7% to 56-3% of the strains at this concentration level. Spiramycin was the least active antibiotic, with 66-3% of the isolates inhibited only by 4 units/ml. In examining the MICs of penicillinase producing isolates (Table II), rosamicin, once again, proved to be more efficient than spiramycin, tetracycline or erythromycin in inhibiting the isolates; penicillin is completely ineffective against P-lactamase producing isolates. For example, 91-5% of non-penirillinase producing isolates had erythromycin MICs of 0-5 ug/ml (Table T) while only 38-5% of the penicillin-resistant isolates
479
480
Correspondence Santoro, J , Kaye, D & Levison, M E In vitro activity of josamycin and rosamicin against Bacteroides fragilis compared with clindamycin, erythromycin, and metronidazole. Antimicrobial Agents and Chemotherapy 10: 188-90 (1976). Siegel, M. S., Thornsberry, G, Biddle, J. W., O'Mara, P. R., Perine, P. L. & Wiesner, P. J. Penicillinase-producing Neisseria gonorrhoeae: results of surveillance in the United States. Journal of Infectious Diseases 137: 170-5 (1978). Sutter, V. L. & Finegold, S. M. Rosamicin: in vitro activity against anaerobes and comparison with erythromycin. Antimicrobial Agents and Chemotherapy 9: 350-1 (1976). Wagman, G. H., Waitz, J. A., Marquez, J., Murawski, A., Oden, E. M., Testa, R. T. & Weinstein, M. G. A new Micromonosporaproduced macrolide antibiotic, rosamicin. Journal of Antibiotics IS: 641-6 (1972). Waitz, J. A., Drube, C. G., Moss Jr, E. L. & Weinstein, M. J. Biological studies with rosamicin, a new Micromonospora-produced macrolide antibiotic. Journal of Antibiotics 25: 647-52 (1972).
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
Dillon, J. R., Eidus, L. & Diena, B. B. CrossCanada susceptibility survey of Neisseria gonorrhoeae isolates to six antimicrobial agents. Canadian Medical Association Journal (1978) in press. Hoyme, U., Baumueller, A. & Madsen, P. O. Rosamicin in urethra! and vaginal secretions and tissues in dogs and rats. Antimicrobial Agents and Chemotherapy 12: 237-9 (1977). Kellogg Jr, D. S., Peacock Jr, W. R., Deacon, W. E., Brown, L. & Pirkle, C. J. Neisseria gonorrhoeae. I. Virulence genetically linked to clonal variation. Journal of Bacteriology 85: 1274-9 (1963). Maier, T. W., Warner, P., Zubryzski, L. & Chila, M. Identification of drug resistance loci in various clinical isolates of Neisseria gonorrhoeae. Antimicrobial Agents and Chemotherapy 12: 444-6 (1977). O'Callaghan, C. H., Morris, A., Kirby, S. M. & Shingler, A. H. Novel method for detection of (3-lactamase by using a chromogenic cephalosporin substrate. Antimicrobial Agents and Chemotherapy 1: 283-8 (1972). Panitz, E. Anticoccidial activity of rosamicin. Journal of Parasitology 60: 530-1 (1974). Sanders, C. C. & Sanders Jr, W. E. In vitro activity of rosamicin against Neisseria and Haemophilus, including penicillinase-producing strains. Antimicrobial Agents and Chemotherapy 12: 293-4 (1977).
Infectious Disease Division, Department of Internal Medicine University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, U.S.A. References Ericsson, H. M., Sherris, J. C. Antibiotic sensitivity testing: report of an international collaborative study. Ada Pathologica et Microbiologica Scandinavica Section B 217 (Suppl.): 1-90 (1971).
Miller, G. H., Arcieri, G., Weinstein, M. J. & Waitz, J. A. Biological activity of netilmicin, a broad-spectrum semisynthetic aminoglycoside antibiotic. Antimicrobial Agents and Chemo-
therapy 10: 827-36 (1976). Steers, E., Foltz, E. L. & Graves, B. S. An inocula replicating apparatus for routine testing of bacterial susceptibility to antibiotics. Antibiotic Chemotherapy 9: 307-11 (1959). Waitz, J. A., Miller, G. H., Moss, E., Jr & Chiu, P. J. S. Chemotherapeutic evaluation of 5-episissomicin (Sch22591), a new semi synthetic aminoglycoside.
Antimicrobial
Chemotherapy 13: 41-8 (1978).
Agents
and
Watanakunakorn, C. Comparative in vitro activity of Sen 20656, netilmicin, gentamicin, and
tobramycin. Antimicrobial Agents and Chemotherapy 10: 382-3 (1976). A comparison of the in vitro activity of rosamkln, erythromycln, spiramycln, penicillin and tetracycline against N. gonorrhoeae, including 0-lactamase producing isolates Sir, The recent emergence of penicillinase-producing isolates of Neisseria gonorrhoeae coupled with their tendency to higher minimum inhibitory concentrations (MICs) for tetracycline and erythromycin (Siegal et al., 1978) has given impetus to the search for new antimicrobials with increased activity against [J-lactamase producing isolates as well as against isolates with reduced sensitivity to penicillin. Rosamicin, a new macrolide antibiotic isolated from Micromonospora rosaria (Wagman et al., 1972) was shown to have increased activity against Gram-negative micro-organisms (Waitz, Drube, Moss & Weinstein, 1972; Crowe & Sanders, 1974), certain anaerobes (Santoro, Kaye & Levison, 1976; Sutter & Fine gold, 1976) and certain coccidial infections (Panitz, 1974) as compared to erythromycin or other macrolide antibiotics. In addition, a recent report, with 50 isolates of N. gonorrhoeae, suggested that rosamicin was very active against this species (Sanders & Sanders, 1977). The present study was undertaken to expand the published data base for N. gonorrhoeae and to compare the activity of rosamicin with penicillin and tetracycline, as well as with the macrolide antibiotics erythromycin and spiramycin. A total of 517 non-penicillinase-producing and 13 peniciUinase-producing N. gonorrhoeae isolates were tested. The penicillinase producing isolates had been sent to the National Neisseria Reference Centre, Laboratory Centre for Disease Control, during the period December 1976 to January 1978. (J-Lactamase positive isolates were tested for the production of penicillinase using the chromogenic cephalosporin nitrocefin (O'Callaghan, Morris Kirby & Shingler, 1972). The other isolates were collected for an antibiotic susceptibility survey in Canada (Dillon, Eidus & Diena, 1978) during the period 1973 to 1974. Prior to testing, all isolates had been stored at -70°C in heart infusion broth (Difco) containing 20% glycerol. In addition, WHO strains HI, V and VII, with different susceptibilities to penicillin, served as control strains
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
enzymes APH (30-1 and n , mediating resistance to neomycin and kanamycin; (2) adcnylating enzyme ANT (2"), mediating resistance to gentamicin and tobramycin; (3) adenylating enzyme ANT (40, mediating resistance to tobramycin and amikacin; (4) acetylating enzyme AAC (20, mediating resistance to gentamicin and tobramycin; (5) acetylating enzyme AAC (3)-I, mediating resistance to gentamicin. 5-episissomicin was not active against resistant strains that possessed the following aminoglycoside inactivating enzymes: (1) acetylating enzyme AAC (3)-II, mediating resistance to gentamicin and tobramycin; and (2) acetylating enzyme AAC (60, mediating resistance to tobramycin and amikacin (Waitz et al., 1978). 5-episissomicin was apparently not highly active against strains that were resistant to all aminoglycosides due to a decreased permeability to aminoglycosides, but 5-episissomicin was among the most active aminoglycosides against this type of resistant strain (Waitz et al., 1978). 5-episissomicin appears to be a promising new semi-synthetic aminocyclitol aminoglycoside and may be valuable when the currently available aminoglycosides lose their activity against a large number of Gram-negative bacilli. Whether 5-episissomicin will be used clinically in the future, will depend on results of extensive toxicologic, pharmacologic and animal studies, and eventually controlled comparative clinical trials. C. WATANAKUNAKORN
477
17.2
22.8
13.5
0.01 0.013 32.3 2.7 3.9 46.8
41.2 20.7 13.3 62.9
0.025 0.05 47.6 56.3 25.7 90.9
0.1 64.4 74.1 66.7 98.1
025 69.8 97.1 91.5 99.8 2.1
0.5 94.8 98.5 98.1 100 83
1.0
25.3
100 98.8 100
2.0
0.03
0.1
7.7 30.8 30-8 38-5 46-2
0003 0.005 0.013 0.025
100
0.25 53.8 38.5
0.5
30.8
76.7 92.3
1.0 100 100
2.0
38.5
4.0
77.0
8.0
Cumulative % inhibition for MIC* of:
7.7
10.0
8.0
66.3 87.8
100
4.0
84.6
16.0
Table 11. MICs of 13 B-lactamase-producingN. gonorrhoeae isolates
*All MICs expressed as pglml except for penicillin and spiramycin which are expressed as units/ml.
Penicillin Tetracycline Erythromycin Rosamicin Spiramycin
Antibiotic
0.2
0003 0.005
Cumulative % inhibition for MIC* of:
99.8
16.0
100
20.0 24.0 32.0
*All MICs expressed as pg/ml except for penicillin and spiramycin which are expressed as unitslml.
Penicillin Tetracycline Erythromycin Rosamicin Spiramycin
Antibiotic
15.4
40.0
20.0
Table I. MICs of 517 isolates of N. gonorrhoeae to rosamicin, erythromycin, spiramycin, penicillin and tetracycline
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
100
>40
24.0
64
100
32.0
Correspondence
were inhibited by this concentration (Table II). Similarly, 62-9 % of the P-lactamase minus strains were inhibited by 0-05(ig /ml rosamicin as compared to 38-5% of the P-lactamase positive isolates. The effect of rosamicin in inhibiting N. gonorrhoeae isolates has been previously investigated with only 50 strains (Sanders & Sanders, 1977). In this study we havetested 530 strains including 13 isolates that are 3lactamase positive. Rosamicin was more active than penicillin, erythromycin, tetracycline or spiramycin in inhibiting these isolates. Pharmacological studies (Waitz et al., 1972) have indicated that rosamicin has similar intraperitoneal, but greater subcutaneous and oral toxicity than erythromycin. However, rosamicin also appears to be better absorbed (Waitz et al., 1972). Recent studies indicate that rosamicin was highly concentrated in human prostatic secretions (Baumueller, 1977) and was present in high concentration in urethral and vaginal secretions of dogs (Hoyme et at., 1977). Because rosamicin is concentrated in vaginal, urethral and prostatic secretions, and in view of its significant activity against isolates of N. gonorrhoeae, further pharmacological studies concerning human toxicity and serum levels are essential. Acknowledgements We wish to thank the Disease Statistics and Operational Planning Section, Laboratory Center for Disease Control, and Mr Y. Mao for their co-operation in computer processing the data. The technical assistance of Mr Peter Lomax is gratefully acknowledged. We also wish to thank Dr B. B. Diena for his critical reading of the manuscript. J. R. DILLON P. D. DUCK L. EIDUS Antimicrobials Section, National Neisseria Reference Centre, Bureau of Bacteriology, Laboratory Centre for Disease Control, Tunney's Pasture, Ottawa, Ontario K1A OL2, Canada References Baumueller, A., Hoyme, U. & Madsen, P. O. Rosamicin—a new drug for the treatment of bacterial prostatitis. Antimicrobial Agents and Chemotherapy 12: 240-2 (1977). Crowe, C. C. & Sanders, Jr, W. E. Rosamitinevaluation in vitro and comparison with erythromycin and lincomycin. Antimicrobial Agents and Chemotherapy 5: 272-5 (1974).
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
for penicillin MICs. These strains were kindly supplied by Dr A. Reyn of the Statens Seruminstitut, Copenhagen. All isolates were subcultured on GC medium base (Difco) containing 1 % v/v of Kellogg's defined supplement (Kellogg, Peacock, Deacon, Brown & Pirkle, 1963). Inoculated plates were incubated for 18 h at 35° in an atmosphere of 5% COi. Agar dilution antibiotic susceptibility testing was carried out using a modified Steer's replicator method (Maier, Warner, Zubryzski & Child, 1977). Antibiotic-containing media were prepared in 400 ml volumes of GC medium base (Difco) to give the following final concentrations: rosamicin (Schering Corporation) 1-0, 0-5, 0-25, 0 1 , 0-05, 0025, 0-010 and 0-005 ng/ml; erythromycin (Sigma) 4-0, 2-0,1-0,0-5,0-25,0-1,0-05 and 0-25 ug/ml; penicillin (Ayerst) 40-0, 20-0, 10-0, 5-0, 2-0, 1-0, 0-5, 0-25, 0-1, 005, 0025 and 0-013 units/ml; spiramycin (Poulence) 640, 32-0, 160, 8-0, 4-0, 20, 1-0 and 0-5 units/ml; and tetracycline HC1 (Bristol Laboratories) 4-0, 2-0, 10, 0-5, 0-25, 0 1 , 0-05, 0-25, 0 1 , 0-05 and 0-025 ug/ml. The minimum inhibitory concentration (MIC) was considered to be that concentration that completely inhibited growth. End points with 1 to 9 colonies were also considered sensitive. The results in Table I, with 517 isolates of N. gonorrhoeae, indicate that rosamicin was considerably more active than penicillin, tetracycline or the macrolide antibiotics erythromycin and spiramycin. Tetracycline and erythromycin concentrations of 0-05 Ug/ml inhibited under 20% of the isolates, while 62-9% and 41-2% of the strains were inhibited by rosamicin and penicillin, respectively. An even greater demarcation in activity is evident at concentrations of 0-1 ug/ml (or units in the case of penicillin). Rosamicin inhibited 90-9 % of the isolates while the other antibiotics inhibited from 25-7% to 56-3% of the strains at this concentration level. Spiramycin was the least active antibiotic, with 66-3% of the isolates inhibited only by 4 units/ml. In examining the MICs of penicillinase producing isolates (Table II), rosamicin, once again, proved to be more efficient than spiramycin, tetracycline or erythromycin in inhibiting the isolates; penicillin is completely ineffective against P-lactamase producing isolates. For example, 91-5% of non-penirillinase producing isolates had erythromycin MICs of 0-5 ug/ml (Table T) while only 38-5% of the penicillin-resistant isolates
479
480
Correspondence Santoro, J , Kaye, D & Levison, M E In vitro activity of josamycin and rosamicin against Bacteroides fragilis compared with clindamycin, erythromycin, and metronidazole. Antimicrobial Agents and Chemotherapy 10: 188-90 (1976). Siegel, M. S., Thornsberry, G, Biddle, J. W., O'Mara, P. R., Perine, P. L. & Wiesner, P. J. Penicillinase-producing Neisseria gonorrhoeae: results of surveillance in the United States. Journal of Infectious Diseases 137: 170-5 (1978). Sutter, V. L. & Finegold, S. M. Rosamicin: in vitro activity against anaerobes and comparison with erythromycin. Antimicrobial Agents and Chemotherapy 9: 350-1 (1976). Wagman, G. H., Waitz, J. A., Marquez, J., Murawski, A., Oden, E. M., Testa, R. T. & Weinstein, M. G. A new Micromonosporaproduced macrolide antibiotic, rosamicin. Journal of Antibiotics IS: 641-6 (1972). Waitz, J. A., Drube, C. G., Moss Jr, E. L. & Weinstein, M. J. Biological studies with rosamicin, a new Micromonospora-produced macrolide antibiotic. Journal of Antibiotics 25: 647-52 (1972).
Downloaded from http://jac.oxfordjournals.org/ at Fudan University on May 11, 2015
Dillon, J. R., Eidus, L. & Diena, B. B. CrossCanada susceptibility survey of Neisseria gonorrhoeae isolates to six antimicrobial agents. Canadian Medical Association Journal (1978) in press. Hoyme, U., Baumueller, A. & Madsen, P. O. Rosamicin in urethra! and vaginal secretions and tissues in dogs and rats. Antimicrobial Agents and Chemotherapy 12: 237-9 (1977). Kellogg Jr, D. S., Peacock Jr, W. R., Deacon, W. E., Brown, L. & Pirkle, C. J. Neisseria gonorrhoeae. I. Virulence genetically linked to clonal variation. Journal of Bacteriology 85: 1274-9 (1963). Maier, T. W., Warner, P., Zubryzski, L. & Chila, M. Identification of drug resistance loci in various clinical isolates of Neisseria gonorrhoeae. Antimicrobial Agents and Chemotherapy 12: 444-6 (1977). O'Callaghan, C. H., Morris, A., Kirby, S. M. & Shingler, A. H. Novel method for detection of (3-lactamase by using a chromogenic cephalosporin substrate. Antimicrobial Agents and Chemotherapy 1: 283-8 (1972). Panitz, E. Anticoccidial activity of rosamicin. Journal of Parasitology 60: 530-1 (1974). Sanders, C. C. & Sanders Jr, W. E. In vitro activity of rosamicin against Neisseria and Haemophilus, including penicillinase-producing strains. Antimicrobial Agents and Chemotherapy 12: 293-4 (1977).
