Antibacterial and pharmacokinetic properties of M14659, a new injectable semisynthetic cephalosporin

In vitro and in vivo antibacterial activities and pharmacokinetics of M14659 were investigated. In vitro activity of M14659 was superior to that of ceftazidime against Staphylococcus aureus. Against Gram-negative bacteria except Pseudomonas aeruginosa, its activity was almost equal to that of ceftazidime. M14659 was more active against P. aeruginosa including multi-drug resistant strains than cefsulodin, cefoperazone or ceftazidime. Affinities of M14659 for penicillin-binding proteins (PBPs) of Escherichia coli and P. aeruginosa were 2 to 14 times higher for PBP-1A and PBP-1B than found for ceftazidime, and almost the same for PBP-3. In vivo activity of M14659 against S. aureus was superior to that of cefamandole, cefotaxime or ceftazidime. Against Gram-negative bacteria including P. aeruginosa, M14659 was 2 to 220 times more active than cefotaxime or ceftazidime. Plasma half-life of M14659 in mice was about 3 times longer than that of ceftazidime. M14659 administered intravenously to mice was mainly excreted in urine without metabolism, and its recovery rate was almost equal to that of ceftazidime.     

Comparative in vitro evaluation of BMY-28142, a new broad-spectrum cephalosporin, versus other beta-lactams against multiresistant gram-negative isolates

The in vitro activity of the new parenteral cephalosporin BMY-28142 was compared with that of cephalothin, cefoxitin, cefotaxime, ceftriaxone, moxalactam, aztreonam and ceftazidime, against a total of 374 recent multiresistant Gram-negative microorganisms of nosocomial origin. Against all species of Enterobacteriaceae resistant to the first- and second-generation cephalosporins, BMY-28142 had superior inhibitory activity than the newer beta-lactams tested, with intrinsic activity against E. coli and Pr. mirabilis slightly less than that of cefotaxime and ceftriaxone. BMY-28142 differed from the other beta-lactams mainly in being at least 16-fold more active against E. cloacae, while BMY-28142 and ceftazidime showed comparable activity against Ps. aeruginosa strains. Against strains of Ps. aeruginosa resistant to both BMY-28142 and amikacin, the combination of the two antibiotics proved to be synergistic in vitro.     

Comparison of the in vitro and in vivo antibacterial activities of cefepime (BMY-28142) with ceftazidime, cefuzonam, cefotaxime and cefmenoxime

Cefepime (BMY-28142), a new semisynthetic cephalosporin, was evaluated for in vitro and in vivo antibacterial activities in comparison with ceftazidime, cefuzonam, cefotaxime and cefmenoxime. Cefepime showed a well-balanced, broad spectrum of activity against a number of clinical isolates collected in Japan. The activity of cefepime against Gram-positive bacteria was several times greater than that of ceftazidime, nearly comparable to cefotaxime and cefmenoxime, and slightly weaker than cefuzonam. Against Enterobacteriaceae, cefepime showed superior activity to the reference cephalosporins against Proteus inconstans, Providencia rettgeri, Morganella morganii, Citrobacter freundii and Enterobacter cloacae. The activity of cefepime against Pseudomonas aeruginosa was nearly comparable to that of ceftazidime. Cefotaxime, cefuzonam and cefmenoxime were substantially less active against P. aeruginosa. Cefepime was more stable than cefuzonam, cefotaxime and cefmenoxime to various types of beta-lactamases from Gram-negative bacteria. The high in vitro activity of cefepime was reflected in its in vivo efficacy against experimental infections in normal and immuno-suppressed mice. Cefepime was the most effective among the cephalosporins tested against four Gram-negative bacterial infections.     

In vitro antibacterial activity and beta-lactamase stability of cefodizime, a new cephalosporin antibiotic

The in vitro activity and beta-lactamase stability of cefodizime (HR 221), a new cephalosporin, were compared with those of other cephem antibiotics. HR 221 was highly active against Gram-negative bacteria. The compound inhibited growth of all tested Haemophilus influenzae strains at 0.10 microgram/ml and showed strong activity even against penicillin-resistant Neisseria gonorrhoeae strains, but it was less effective against Pseudomonas aeruginosa than the other antibiotics tested. Against Gram-positive bacteria, HR 221 showed 100% inhibition of growth of Streptococcus pneumoniae at 0.39 microgram/ml, and it was slightly less active against Staphylococcus aureus (MIC90:12.5 micrograms/ml) than other antibiotics such as cefotaxime (CTX). The bactericidal activity of HR 221 against E. coli was dose-related and comparable to that of CTX, cefoperazone and latamoxef. The bactericidal activity of the compound at medium concentrations simulating human serum levels was higher than that of CTX and cefmetazole, and no cell regrowth was noted after beta-lactamase-induced inactivation of the compound. HR 221 was stable to most drug-inactivating enzyme preparations from various bacterial species.     

Antibacterial activity of BMY-28142, a novel broad-spectrum cephalosporin

BMY-28142, 7-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3- (1-methylpyrrolidinio)methyl-3-cephem-4-carboxylate, exhibited a well-balanced, extended-spectrum of antibacterial activity both in vitro and in vivo. Against Staphylococci and Streptococci, BMY-28142 was about four to ten times more active than ceftazidime and comparable to cefotaxime. Most Enterobacteriaceae were more susceptible to BMY-28142 than to ceftazidime, though strains of Pseudomonas aeruginosa were slightly more sensitive to ceftazidime. BMY-28142 showed potent activity against Gram-negative bacteria resistant to ceftazidime and/or cefotaxime. Bactericidal activity of BMY-28142 against 10 strains of P. aeruginosa was superior to that of ceftazidime. In bacterial infection models in mice, BMY-28142 was more effective than ceftazidime against three Gram-positive and three Gram-negative pathogens. The anti-pseudomonal in vivo activity of BMY-28142 was nearly comparable to that of ceftazidime. The blood levels and urinary excretion rates of BMY-28142 in mice were similar to those of ceftazidime.     

Cefotaxime: microbiology, pharmacology, and clinical use

The microbiological activity, pharmacology, and clinical efficacy of the third-generation cephalosporin cefotaxime are reviewed. Cefotaxime has greater activity than other available first- and second-generation cephalosporins against Enterobacteriaceae. It is more active than older cephalosporins against Pseudomonas aeruginosa and Acinetobacter spp., but most strains are still considered resistant. Cefotaxime is also active against some gram-negative bacilli that are resistant to aminoglycosides, including amikacin. Cefotaxime has activity comparable with other cephalosporins against gram-positive cocci, except staphylococci and enterococci, which are resistant. Cefotaxime in combination with penicillins or aminoglycosides may be synergistic against selected gram-negative bacilli. Cefotaxime is metabolized in vivo to the desacetyl derivative, which is also microbiologically active. Cefotaxime appears to penetrate most body tissues and fluids, including cerebrospinal fluid. Clinical use of cefotaxime has resulted in response rates between 70 and 95% in most infections. The ultimate role of cefotaxime and other third-generation cephalosporins is not established since controlled clinical comparisons with standard antimicrobial regimens are lacking. Possibilities include the empiric and specific therapy of serious gram-negative bacillary infection probably in combination with a penicillin or an aminoglycoside. Cefotaxime appears to be potentially useful in the management of gram-negative bacillary meningitis.     

Experimental efficacy and pharmacokinetic properties of cefpiramide, a new cephalosporin

The in vivo therapeutic efficacy of cefpiramide was investigated and compared with that of cefoperazone. Cefpiramide was more potent than cefoperazone against infections produced by both beta-lactamase-producing and non-beta-lactamase-producing S. aureus. The protective activity of cefpiramide against experimental infections with selected members of Enterobacteriaceae was lower than that of cefoperazone. Against carbenicillin-resistant P. aeruginosa infections, cefpiramide was as active as gentamicin and aztreonam and three times more potent than cefoperazone, cefotaxime and piperacillin. The pharmacokinetic properties of cefpiramide in mice and rats were superior to those of cefotaxime and cefoperazone. The peak serum concentrations of cefpiramide, administered subcutaneously at a dose of 50 mg/kg, were 76 micrograms/ml in mice and 174 micrograms/ml in rats and the corresponding serum half-lives of cefpiramide were 87 min and 49 min in mice and rats respectively.     

Susceptibility of clinical isolates to cefotaxime

Susceptibilities of 737 strains of 19 species of bacteria to cefotaxime (CTX) were determined based on the inhibition zone diameter obtained by the single-disc method. Four categories were assessed. 1. Susceptibility of clinical isolates to CTX and 6 other antibiotics Against most strains, CTX showed higher antibacterial activity than other drugs (CET, ABPC, SBPC, CMZ, GM, AMK), especially for S. pneumoniae, S. pyogenes and S. agalactiae. Furthermore, CTX was more active than the other antibiotics against E. coli, Indole (+) Proteus, P. mirabilis, Klebsiella sp., S. marcescens, H. influenzae and E. cloacae. 2. Susceptibility of strains isolated from different clinical materials CTX showed the highest antibacterial activity against most strains isolated from sputum, urine, pus, blood and cerebrospinal fluid. However, CTX was occasionally less than potent AMK and GM against strains isolated from bile. Against P. aeruginosa strains derived from clinical materials, the following results were obtained: AMK greater than CFS, FOM greater than CTX greater than GM greater than SBPC 3. Susceptibility of clinical isolates in 7 different fields CTX was the most active antibiotic tested in the fields of internal medicine, pediatrics, urology, obstetrics & gynecology, dermatology and otorhinolaryngology. But in surgery, CTX was less potent than GM and AMK. 4. Susceptibility of clinical isolates of inpatients and outpatients CTX showed excellent activity against many beta-lactamase resistant strains isolated from patients.     

Antimicrobial susceptibility of clinical isolates of aerobic Gram-negative bacteria in 2006

We determined MICs of antibacterial agents against 1280 clinical strains of aerobic Gram-negative bacteria (19 genus or species) isolated at 16 Japanese facilities in 2006. MICs were determined using mostly broth microdilution method and antibacterial activity was assessed. Strains producing extended-spectrum beta-lactamases (ESBL) accounted for 3.7% of Escherichia coli, 2.7% of Klebsiella spp., and 11.4% of Proteus spp. Notably, 18.8% of Proteus mirabilis was found to produce ESBL higher than 16.7% in 2004. This result was higher extremely than other species. Among Haemophilus influenzae, only 1.2% produced beta-lactamase and 62.8% that increased compared with 57.7% in 2004, were beta-lactamase-negative ampicillin-resistant strains when classified by penicillin-binding protein 3 mutation. Although few antibacterial agents against Pseudomonas aeruginosa have potent activity, only three agents--doripenem, ciprofloxacin, and tobramycin-showed an MIC90 of 4 microg/mL. Of all P aeruginosa strains, 5.7% were resistant to six or more agents of nine antipseudomonal agents, a decrease compared to 8.7% in 2004. Against other glucose-non-fermentative Gram-negative bacteria, the activity of most antibacterial agents was similar to that in 2004.     

In vitro and in vivo antibacterial activity of the new semisynthetic cephalosporin cefpirome

Cefpirome (HR 810), a new semisynthetic cephalosporin derivative, was found to have a broad antibacterial spectrum against gram-positive and gram-negative bacteria. Against Staphylococcus aureus, cefpirome was more active than not only cefotaxime and ceftazidime but also cefotiam. Against gram-negative bacteria, especially, Enterobacter cloacae and Citrobacter freundii, it was also more active than the other antibiotics tested, but against Pseudomonas aeruginosa, it was less active than ceftazidime. Cefpirome was stable to hydrolysis by the common plasmid mediated beta-lactamases and was stable to the action of chromosomal cephalosporinases. But it was slightly hydrolyzed by both Rms 213 mediated penicillinase and oxyiminocephalosporinases produced by Proteus vulgaris and Pseudomonas cepacia. When cefpirome was administered subcutaneously to mice experimentally infected with Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae or Pseudomonas aeruginosa, its efficacy well reflected its in vitro potency.     

Relationship between protein binding and antimicrobial activities of antibiotics against Streptococcus pneumoniae and Haemophilus influenzae

Fifty isolates of Streptococcus pneumoniae and 42 isolates of Haemophilus influenzae were isolated from the blood of children admitted to pediatric wards of hospitals in subprefucture between January 1998 and December 2005. The susceptibilities were measured by a microbroth dilution method using a standard broth and a broth containing 4.5% albumin. Against S. pneumoniae, penicillin G, ampicillin, cefotaxime, ceftriaxone, panipenem, meropenem, vancomycin, cefditoren, cefcapene, cefteram, faropenem and tebipenem were used and against H. influenzae, ampicillin, piperacillin, cefotaxime, ceftriaxone, panipenem, meropenem, clavulanic acid/ amoxicillin, cefditoren, cefcapene, cefteram, faropenem and tebipenem were used. Against S. pneumoniae, tebipenem was the highest antimicrobial activity in oral antibiotics (MIC90; < or = 0.06 microg/ml) and panipenem showed the highest activity for intravenous antibiotics (MIC90; < or = 0.12 microg/ml). Against H. influenzae, cefditoren was the highest activity for oral antibiotics (MIC90; < or = 0.06 microg/ml) and meropenem showed the highest activity for intravenous antibiotics (MIC90; < or = 50.06 microg/ml). The MIC90s measured by albumin containing broth were higher than those measured by standard broth. Protein binding rates of ceftriaxone, cefditoren, and faropenem were greater than 90%, and the MIC90 of these antibiotics measured by albumin addition methods were over 4-fold higher than those measured by standard methods.     

Beta-lactamase stability and antibacterial activity of cefpirome alone and in combination with other antibiotics

The antibacterial activity of cefpirome (HR810), a new cephalosporin, was compared with that of other "third-generation" cephalosporins, as well as cefuroxime, piperacillin and gentamicin. Cefpirome was the most active beta-lactam antibiotic against Gram-negative bacteria. The MIC90 for Enterobacteriaceae was always less than 0.5 ml/l except for Enterobacter species. The MIC90 against Pseudomonas species was 2 mg/l, which was equal to that of ceftazidime and gentamicin. Cefpirome was also more active than the other beta-lactam antibiotics against Staphylococcus aureus. A relatively high frequency of synergy was observed when cefpirome was combined with aminoglycosides against both Gram-positive and Gram-negative bacteria. No antagonism was detected. This antibiotic was very stable to both plasmid- and chromosomally-mediated beta-lactamases. It was more resistant to Enterobacter cloacae P99 enzyme than ceftazidime, cefotaxime and cefotetan. Its stability to the Klebsiella K1 beta-lactamase was more than that of cefotaxime and ceftriaxone but slightly less than that of ceftazidime and latamoxef. MBC90 values for cefpirome were generally less than twice the corresponding MIC values.     

Cefotaxime. A review of its antibacterial activity, pharmacological properties and therapeutic use

Synopsis: Cefotaxime is a new 'third generation' semisynthetic cephalosporin administered intravenously or intramuscularly. It has a broad spectrum of activity against Gram-positive and Gram-negative aerobic and anaerobic bacteria, and is generally more active against Gram-negative bacteria than the 'first' and 'second generation' cephalosporins. Although cefotaxime has some activity against Pseudomonas aeruginosa, on the basis of present evidence it cannot be recommended as sole antibiotic therapy for pseudomonal infections. However, cefotaxime has been effective in treating infections due to other 'difficult' organisms, such as multidrug-resistant Enterobacteriaceae. Like other cephalosporins, cefotaxime is effective in treating patients with complicated urinary tract and lower respiratory tract infections, particularly pneumonia caused by Gram-negative bacilli. High response rates have also been achieved in patients with Gram-negative bacteraemia. Although favourable clinical results have been obtained in patients with infections caused by mixed aerobic/anaerobic organisms (such as peritonitis or soft tissue infections), the relatively low in vitro activity of cefotaxime against Bacteroides fragilis may restrict its usage in situations where this organism is the suspected or proven pathogen. In preliminary studies, males and females treated with a single intramuscular dose of cefotaxime for uncomplicated gonorrhoea caused by penicillinase-producing strains of Neisseria gonorrhoeae responded very favourably. Encouraging results have also been reported in open studies in children including neonates, treated with cefotaxime for meningitis and various other serious infections. In some situations, cefotaxime has been given in combination with another antibiotic such as an aminoglycoside, but the merits of such a combination have not been clearly established. Whether cefotaxime alone is appropriate therapy for conditions previously treated with aminoglycosides (other than pseudomonal infections) also needs additional clarification, but if established as equally effective in such conditions cefotaxime offers potentially important clinical and practical advantages in its apparent lack of serious adverse effects and freedom from the need to undertake drug plasma concentration monitoring.     

Comparative activity of ceftizoxime against aminoglycoside-resistant aerobic gram-negative bacilli

The in vitro activity of ceftizoxime was compared with that of other beta-lactam antibiotics against 331 aminoglycoside (AG)-resistant clinical isolates. Two hundred and six AG-resistant, beta-lactamase producing, R-plasmid harbouring Enterobacteriaceae strains had MICs ranging from 0.0125 to 0.063 mg/l. AG-resistant Escherichia coli (36 strains) and Klebsiella pneumoniae (19) had MIC 90 values of 8 mg/l. Proteus rettgeri and P. vulgaris as well as Morganella morganii, resistant to several AGs, had MICs ranging from 0.5 to 4 mg/ml. Against all six isolates of AG-resistant Salmonella enteritidis the MIC90 was 0.5 mg/l. Twenty-seven strains of Serratia marcescens, most of which were resistant to beta-lactam and AG antibiotics, had MICs ranging from 0.5 to 8 mg/l. The AG-resistant strains of Enterobacteriaceae producing several AG-modifying enzymes (AAC(3); AAC(2'); AAC(6'); APH(3')) showed MICs ranging from 0.6 to 4 mg/l. Against 10 AG-resistant strains of Pseudomonas aeruginosa producing AAC(3), AAC(6') and APH(3') enzymes, the MICs ranged from 16 to 64 mg/l. In conclusion, ceftizoxime was equally or more active than cefotaxime, cefoperazone, ceftazidime and moxalactam against AG-resistant E. coli, Klebsiella, Morganella, Proteus, Serratia, Salmonella and R-plasmid harbouring Enterobacteriaceae. Ceftizoxime was less active than cefotaxime, moxalactam and ceftazidime against P. aeruginosa.     

In vitro and in vivo antibacterial activities of meropenem, a new carbapenem antibiotic.

The in vitro and in vivo antibacterial activities of meropenem were compared with those of imipenem, ceftazidime, flomoxef, cefuzonam and cefotiam. Meropenem showed a broad antibacterial spectrum against clinical isolates of Gram-positive and Gram-negative bacteria. Against Gram-negative bacteria, with the exception of Acinetobacter calcoaceticus, meropenem exhibited the most potent activity among the drugs tested. It inhibited all 330 strains of Enterobacteriaceae at 0.78 mg/l. Meropenem was sensitive against several cephem-resistant strains of Enterobacteriaceae. Against Pseudomonas aeruginosa, meropenem was four-fold more active than imipenem and eight-fold more active than ceftazidime, with an MIC90 of 0.78 mg/l. The therapeutic effect of meropenem on systemic infection in mice was ten to twenty-fold less than that of imipenem against Staphylococcus aureus, Streptococcus pyogenes and Streptococcus pneumoniae. However, meropenem was as effective as imipenem on infections of Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, Acinetobacter calcoaceticus and Pseudomonas aeruginosa. Meropenem was eliminated from mice plasma two-fold faster than imipenem, with a plasma half-life of 7.6 min. From the above results the authors concluded that meropenem is a promising drug for clinical use.     

Antibacterial activity of panipenem against clinical isolates in 2000 and 2001

As the post-marketing surveillance of panipenem/betamipron (Carbenin), MICs of panipenem (PAPM) against 1355 clinical isolates of 28 species from 15 medical institutions all over Japan from June 2000 to March 2001 were measured using the broth microdilution method approved by the Japanese Society of Chemotherapy and compared with those of parenteral carbapenem antibacterials, imipenem (IPM) and meropenem (MEPM), and parenteral cephem antibacterials, cefozopran, cefepime, and sulbactam/cefoperazone. The activity of PAPM was comparable to that of IPM against almost all species tested. Compared with MEPM, PAPM was more active against Gram-positive bacteria and Bacteroides spp., and less active against Gram-negative bacteria. Compared with the parenteral cephems, PAPM was more active against most of species tested and its MIC ranges were narrower than those of the cephems as were those of other carbapenems. In this surveillance study, the incidence of resistance in various species were as follows: 39.3% for methicillin-resistant Staphylococcus aureus, 47.3% for penicillin-intermediate Streptococcus pneumoniae (PISP), 15.1% for penicillin-resistant S. pneumoniae (PRSP), 0.9% for extended-spectrum beta-lactamase (ESBL) producing Escherichia coli, 3.4% for ESBL producing Klebsiella pneumoniae, 19.2% for beta-lactamase producing Haemophilus influenzae, 24.0% for beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae, and 1.0% for metallo-beta-lactamase producing Pseudomonas aeruginosa. Against these resistant strains, carbapenems including PAPM showed generally more potent activity than cephems. It was noted that PAPM showed the most potent activity against PISP and PRSP, which showed high incidence of 62.4% totally, among tested drugs. Metallo-beta-lactamase producing P. aeruginosa exhibited high resistance and BLNAR H. influenzae also exhibited low susceptibility against all tested drugs. But no remarkable change in the activity of PAPM against other species was observed in this study compared with that in the studies before the marketing of Carbenin. Furthermore, it is necessary to pay much attention to the trend of resistant strains such as PRSP, metallo-beta-lactamase producing bacteria, and BLNAR H. influenzae.     

Comparison of in vitro antibacterial activities of new cephems against clinical organisms (isolated between June 1983 and January 1984)

We compared the in vitro antibacterial activities of ceftizoxime (CZX), cefotaxime (CTX), cefmenoxime (CMX), cefoperazone (CPZ), ceftazidime (CAZ), latamoxef (LMOX) and cefotetan (CTT) against 2,729 strains of 11 organisms freshly isolated from 10 medical institutions in Japan between June 1983 and January 1984 and obtained the following results: Against S. pyogenes, LMOX and CTT, which have the methoxy group at the 7 position, were less active than the other drugs. LMOX inhibited 80% of S. pyogenes at 0.78 micrograms/ml; CTT, at 1.56 micrograms/ml; but CZX and CTX inhibited 100% at 0.025 micrograms/ml or lower; CMX, at 0.05 micrograms/ml; and CPZ and CAZ, at 0.20 micrograms/ml. Against H. influenzae, E. coli, K. pneumoniae, P. mirabilis and indole-positive Proteus, these test antibiotics, especially CZX, CTX and CMX, which have the aminothiazolyl methoxyimino group, were potently active. Against S. marcescens CZX and CAZ were more active than the other drugs and against P. aeruginosa CAZ was more active than the other drugs. The test organisms did not tend to acquire resistance to these cephems when our results were compared with the results obtained at the development period.     

我院临床致病菌分布及耐药性分析

目的:分析临床致病菌的分布和耐药特性,为临床合理用药提供参考。方法:采用细菌培养、分离和鉴别以及K-B纸片扩散法对分离菌进行药敏检测。结果:常见的菌株在痰标本中以肺炎克雷伯菌、铜绿假单胞菌为多见;尿液标本中以肠球菌属、大肠埃希菌为多见;粪便标本中以福氏志贺菌为主。在大多数科室送检的痰标本中均检出铜绿假单胞菌。结论:MRSA和MRCNS对β内酰胺类、氨基糖苷类和喹诺酮类抗菌药物较MSSA和MSCNS耐药,耐-药率>80%;产ESBLs菌株对包括头孢吡肟、头孢噻肟、头孢他啶等β内酰胺类及氨基糖苷类、喹诺酮类抗菌药物的-耐药率高于ESBLs阴性株;头孢他啶对铜绿假单胞菌作用优于头孢噻肟,未发现万古霉素和替考拉宁的耐药株。     

A Comparison of Choline Magnesium Trisalicylate and Acetylsalicylic Acid in Patients with Rheumatoid Arthritis

Summary

Five newer beta-lactam antibiotics and two aminoglycosides were tested on 400 freshly isolated clinically significant organisms from specimens at a district general hospital. All the antibiotics had very broad-spectrum activities but none could cover against all probable pathogens. Latamoxef was the best of all against Bacteroides spp. Aminoglycosides, followed by cefotaxime and ceftizoxime, were best against staphylococci. Tobramycin, followed by ceftazidine and netilmicin, had the best activity against Pseudomonas aeruginosa. Of all 7 antibiotics tested only piperacillin demonstrated activity against Streptococcus faecalis. Cefotaxime and ceftizoxime were the best against Escherichia coli, Klebsiella spp. and most of streptococci. The study demonstrated that safer alternatives to aminoglycosides are now available.     

The in vitro antibacterial activity of ceftriaxone in comparison with nine other antibiotics

Summary

The results of a large three centre co-ordinated study into the in vitro susceptibility of bacterial clinical pathogens showed no significant evidence of regional variation within the U.K. towards the 10 antibiotics examined. The newer cephalosporins were highly potent and superior to other antibiotics against the Enterobacteriaceae, with ceftriaxone and cefotaxime the most potent. Against Pseudomonas aeruginosa, gentamicin was the most active, followed by ceftazidime, piperacillin and ceftriaxone; cefotetan was the least active. Staphylococcus aureus and Staphylococcus albus were most susceptible to cefuroxime and gentamicin, though most were also susceptible to ceftriaxone, cefotaxime and cefoxitin. Streptococcus (Groups A and B), Streptococcus pneumoniae and Neisseria spp. were susceptible to most agents other than gentamicin, but ceftriaxone and cefotaxime were overall the most potent. Ceftriaxone was the most active agent against Haemophilus influenzae. The newer agents were variable and relatively poor against anaerobes and only amoxycillin and piperacillin were significantly active against Streptococcus faecalis. The overall resistance level to the third generation cephalosporins was low.