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PubMed1993

In vitro antimicrobial susceptibility to combinations of drugs on bacteria from carious and endodontic lesions of human deciduous teeth.

The purpose of this study was to clarify the antibacterial efficacy of mixed antibacterial drugs on bacteria of carious and endodontic lesions of human deciduous teeth in vitro. The antibacterial drugs used in this study were mixtures of ciprofloxacin, metronidazole, plus a third antibiotic: amoxicillin, cefaclor, cefroxadine, fosfomycin or rokitamycin. Samples taken from carious dentin (17 cases) and infected pulpal tissues (14 cases) were cultured on control plates and plates containing the mixed drugs. No bacteria were recovered in the presence of any combination of the mixture of the drugs (100 micrograms each/ml), and the bacterial growth occurred on control plates (10(1) to 10(7) colony-forming units), indicating that the mixed drugs inhibit the growth of bacteria in the samples. When carious and endodontic lesions on split surfaces of freshly extracted teeth were covered overnight with alpha-tricalcium phosphate cement containing a mixture of ciprofloxacin, metronidazole and cefaclor (1% each; 5 cases), no bacteria were recovered from the lesions. No bacteria were recovered from carious and endodontic lesions when these lesions were immersed in a solution of the mixture (200 micrograms each/ml; 5 cases). These findings indicate that carious and endodontic lesions can be sterilized by the mixed drugs in situ.

Amoxicillin↗
PubMed1993

In vitro antimicrobial susceptibility of different serotypes of Actinobacillus actinomycetemcomitans.

In vitro susceptibility of Actinobacillus actinomycetemcomitans (A.a.) serotypes to selected antimicrobial agents was investigated by the agar dilution method on supplemented Mueller-Hinton test medium. Eighty-three A.a. strains, 80 recent isolates from 40 periodontally healthy or diseased subjects, and three type strains were included in the study. Serotype a represented 20, serotype b 32, serotype c 17, and serotype e 7 and nontypable 4 of the tested strains. The most effective drugs against all A.a. serotypes in vitro were cefaclor, cefuroxime, tetracycline hydrochloride, doxycycline, trimethoprim-sulfamethoxazole (cotrimoxazole), and ciprofloxacin, which inhibited 100% of the strains at 4.0 micrograms/ml, 4.0 micrograms/ml, 1.0 microgram/ml, 2.0 micrograms/ml, 0.06 microgram/ml, and 0.015 microgram/ml, respectively. Serotypes a and e were more susceptible to cefaclor and cefuroxime than were serotypes b and c; 100% of the first two groups were inhibited at 2.0 micrograms/ml and 1.0 microgram/ml. Ampicillin inhibited 92% of the tested strains at 1.0 microgram/ml. Serotype b was always susceptible to ampicillin. Metronidazole exhibited the best activity against serotype a strains. The lowest minimal inhibitory concentration values for benzylpenicillin, ampicillin, erythromycin, doxycycline, and metronidazole were encountered among serotype b isolates. The results of the present study indicate minor differences in the in vitro antimicrobial susceptibility patterns of different A.a. serotypes, except to metronidazole. Also, the new oral cephalosporins and cotrimoxazole, rare antimicrobial agents in periodontology, showed promising efficacy against all A.a. strains.

Aggregatibacter actinomycetemcomitans↗
PubMed1985

In vitro activity of Ro 15-8074, a new oral cephalosporin, against Neisseria gonorrhoeae.

Ro 15-8074, a new cephalosporin the pivaloyloxymethylester of which (Ro 15-8075) is orally absorbable, showed greater in vitro activity than cefaclor against 48 Neisseria gonorrhoeae strains, including 25 penicillinase-producing strains. Unlike cefaclor, Ro 15-8074 was unaffected by increase in inoculum size, and it exhibited a remarkable stability against gonococcal beta-lactamase hydrolysis.

Amoxicillin↗
PubMed1986

The effect of antimicrobial agents on fecal flora of children.

Influences of antibiotics on the fecal flora in children were studied for oral ampicillin, penicillin V, erythromycin, cefaclor, and gentamicin and for intravenous ampicillin, methicillin, cefpiramide, and ceftazidime. All antibiotics affected the normal flora, although the quality and quantity of the changes were variable. No substantial differences were noted between the oral and intravenous use of ampicillin with regard to its effect on the flora. Three penicillins, ampicillin, penicillin V, and methicillin, caused remarkable changes. The characteristic pattern observed was the considerable suppression of Bifidobacterium, Streptococcus, and Lactobacillus species. Although enterobacteria did not significantly change in number, Klebsiella spp. frequently replaced Escherichia coli. In patients given erythromycin and cefaclor, the reduction in the number of Bifidobacterium spp. was 1 log10 and that of members of the family Enterobacteriaceae was 3 log10. Gentamicin administered orally caused a drastic change, including a remarkable decline of E. coli to less than 2 log10/g of feces. Cefpiramide, a parenteral expanded-spectrum cephalosporin, suppressed normal flora so markedly that almost all species of organisms were eradicated, and the active growth of yeasts was promoted (2.6 log10 increase). Ceftazidime caused similar changes as cefpiramide, but the changes were less extensive. Yeasts increased after treatment with most antibiotic groups. This increase was particularly prominent in patients given oral penicillins and expanded-spectrum cephalosporins.

Administration, Oral↗
PubMed1987

In vivo evaluation of tigemonam, a novel oral monobactam.

Tigemonam, a new monobactam with excellent activity against gram-negative bacteria, was evaluated for in vivo efficacy and absorption after oral administration to laboratory animals. Tigemonam is absorbed when administered orally to mice and dogs. In a variety of gram-negative systemic infections in mice, orally administered tigemonam was efficacious in all infections studied. Comparison drugs such as amoxicillin, cephalexin, and cefaclor were less efficacious, especially in infections caused by beta-lactamase-producing organisms. In localized infections, tigemonam also demonstrated excellent in vivo activity. In acute pyelonephritis in mice caused by Escherichia coli or Proteus sp., tigemonam was very effective. In a rat lung model with Klebsiella pneumoniae, tigemonam was active with a median effective dose of 46 mg/kg compared with 160 mg/kg for cefaclor and over 200 mg/kg for amoxicillin. Tigemonam was well absorbed in laboratory animals and with its excellent gram-negative spectrum of activity should prove of value in oral antibiotic therapy in humans.

Acute Disease↗
PubMed1988

In vitro activity of an oral iminomethoxy aminothiazolyl cephalosporin, R-3746.

The in vitro activity of R-3746, an iminomethoxy aminothiazolyl cephalosporin with a CH2OCH3 moiety at position 3, was compared with those of other antibiotics. R-3746 inhibited the majority of hemolytic streptococci (groups A, B, C, F, and G) and Streptococcus pneumoniae at less than 0.06 micrograms/ml, which was comparable to the activity of amoxicillin, 2- to 8-fold more active than cefixime, and 16- to 64-fold more active than cefaclor and cephalexin. Ninety percent of beta-lactamase-producing Haemophilus influenzae and Neisseria gonorrhoeae were inhibited at a concentration 0.25 micrograms/ml, but it was less active against Branhamella spp. It did not inhibit (MIC, greater than 16 micrograms/ml) enterococci, viridans group streptococci, or methicillin-resistant staphylococci. The MICs of R-3746 for 90% of strains tested for Escherichia coli; Klebsiella pneumoniae; Citrobacter diversus; Proteus mirabilis; and Salmonella, Shigella, and Yersinia spp. were less than or equal to 1 micrograms/ml. It was two- to eightfold less active than cefixime but was markedly superior to cefaclor, cephalexin, amoxicillin-clavulanate, and trimethoprimsulfamethoxazole. R-3746 inhibited 50% of Enterobacter cloacae, Enterobacter aerogenes, Citrobacter freundii, Morganella spp., Providencia spp., Proteus vulgaris, and Serratia marcescens at less than or equal to 8 micrograms/ml. Pseudomonas spp. were resistant. Fifty percent of Clostridium spp. were inhibited by 0.5 micrograms/ml, but MICs for Bacteroides spp. were greater than 128 micrograms/ml. R-3746 was not appreciably hydrolyzed by most chromosomal and plasmid-mediated beta-lactamases.

Amoxicillin↗
PubMed1987

In vitro activity of Ro 19-5247 (T-2525) and interpretive criteria for disk diffusion susceptibility testing.

The activity of Ro 19-5247 (the active metabolite of the oral cephalosporin Ro 19-5248 [T-2588]) was compared with that of five orally active agents against a total of 331 bacterial strains. Ro 19-5247 was more active in vitro than amoxicillin, amoxicillin-clavulanate, cefaclor, cefuroxime, and cephalexin against members of the family Enterobacteriaceae. Amoxicillin-clavulanate and amoxicillin overall were more active than the other four agents against staphylococci. Ro 19-5247, amoxicillin-clavulanate, amoxicillin, and cefuroxime were equally active against nonenterococcal streptococci and more active than cefaclor and cephalexin. All six agents showed little or no activity against nonfermentative gram-negative bacteria. Against Streptococcus (Enterococcus) faecalis, only amoxicillin and amoxicillin-clavulanate were active. The interpretive criteria for in vitro susceptibility testing with 10- and 30-micrograms Ro 19-5247 disks were established by regression analysis to correlate the inhibitory zone sizes and MICs for the bacterial isolates. The suggested tentative zone size breakpoints for the 10-micrograms disk are as follows: susceptible, greater than or equal to 22 mm (MIC, less than or equal to 2 micrograms/ml); moderately susceptible, 20 to 21 mm (MIC, 4 micrograms/ml); and resistant, less than or equal to 19 mm (MIC, greater than or equal to 8 micrograms/ml).

Acinetobacter↗
PubMed2003

Clarithromycin inhibits the development of dermatitis in NC/Nga mice.

BACKGROUND: Colonization of Staphylococcus aureus on the skin is one of the exacerbating factors of atopic dermatitis (AD). Reduction of bacterial colonization in these lesions was reported to be effective for the treatment of subjects with AD. Clinical trials have demonstrated the efficacy of FK-506 (an immunosuppressive macrolide) ointment for AD, and many case reports have been published regarding its positive effects for other inflammatory skin diseases. Clarithromycin (CAM) is a macrolide antibiotic with immunological effects. One patient with AD was treated effectively with oral CAM for Helicobacter pylori infection. NC/Nga (NC) mice have recently been recognized to be a model of AD. METHODS: We examined the effects of CAM on the development of dermatitis, infiltration of mast cells and MHC class II-positive cells in the skin and the colonization of S. aureus on the skin of NC mice. CAM was compared with cefaclor, an antibiotic with no immunological effects. RESULTS: CAM suppressed the development of dermatitis at 5 and 6 weeks to a statistically significant degree, and these effects gradually weakened, but the severity of the dermis of CAM-treated mice was milder than in control mice. Dexamethasone was effective in the case of development of dermatitis at 5 weeks. These effects gradually weakened, and the difference between dexamethasone-treated mice and control mice disappeared. The severity of the skin lesions in CAM-treated mice was the lowest of the three groups at 9 weeks of observation. Histological analyses revealed that infiltration of inflammatory cells, especially degranulated mast cells and MHC class II-positive cells, was significantly reduced. Thickening of the epidermis and hyperkeratosis in CAM-treated mice were less than in control mice. CAM and cefaclor completely inhibited S. aureus on the skin of NC mice, for all experimental periods. Dexamethasone provided inhibition at 5 weeks, but eventually the difference between dexamethasone-treated mice and control mice disappeared. CONCLUSIONS: CAM inhibited the development of dermatitis for the first half of the experimental period in NC mice as a result of antibacterial and immunological effects. Our data show that CAM can be an effective antibiotic for AD with respect to delaying the development of dermatitis.

Animals↗
PubMed1992

Cefetamet pivoxil in pediatric otitis media.

Cefetamet, an oral 3rd-generation cephalosporin, was investigated in 40 children with acute otitis media in a comparative randomized trial. The efficacy of 20 mg/kg cefetamet syrup in 20 patients was compared with that of 20 mg/kg cefaclor in another 20, both drugs being given orally twice daily for 7 days. Tympanocentesis was performed for every child before the initiation of antimicrobial treatment. After 7 days treatment with cefetamet pivoxil, clinical cure was obtained in 12 patients, 3 were failures and 5 could not be assessed. In the cefaclor group, 10 patients were cured, 1 improved and 9 were failures. No severe adverse events were observed with either drug.

Acute Disease↗
PubMedDate not supplied

Cefetamet in the treatment of acute sinusitis in adult patients.

Cefetamet, an oral third-generation cephalosporin, was investigated in a prospective, randomized, open, comparative trial in 41 outpatients with acute sinusitis. The efficacy of 500 mg cefetamet given orally twice daily for 7 days to 22 patients was compared with that of 500 mg cefaclor given orally three times daily for 7 days to 19 patients. Sinus punctures were performed before antimicrobial therapy in 10 patients from each treatment group. A successful bacteriological response was obtained in all the 21 assessable patients treated with cefetamet and in the cefaclor-treated group 18 assessable patients were cured and two were improved, but one failed to respond to therapy. The tolerability of both drugs was good and no withdrawals from treatment were necessary.

Acute Disease↗
PubMed1996

In vitro activity of cefdinir against respiratory pathogens isolated in Sicily with reference to beta-lactamase production.

The in vitro activity of cefdinir (CI-983, FK-482), an orally absorbed aminothiazolyl cephalosporin, was evaluated against all 287 strains of Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, Streptococcus pneumoniae and Streptococcus pyogenes in comparison with cefaclor, cefuroxime, amoxicillin, amoxicillin-clavulanic acid, erythromycin and cotrimoxazole. The bactericidal activity of cefdinir, cotrimoxazole, amoxicillin-clavulanic acid and erythromycin was determined against H. influenzae, M. catarrhalis and S. pneumoniae. With the exception of one beta-lactamase negative ampicillin-resistant strain of H. influenzae (resistant to all antibiotics tested), no resistance to cefdinir was observed (MIC < or = 1 mg/l). Cefdinir was active against H. influenzae, H. parainfluenzae and M. catarrhalis regardless of whether or not they produced beta-lactamase. In general, the inhibitory concentrations of cefdinir against H. influenzae, H. parainfluenzae and M. catarrhalis were similar to those of amoxicillin/clavulanic acid, one or two dilutions lower than those of cefuroxime and four dilutions lower than those of cefaclor and cotrimoxazole. Against S. pneumoniae and S. pyogenes cefdinir had the same activity as cefuroxime and amoxicillin but was more effective than the other antibiotics tested. Kinetic studies showed that cefdinir was rapidly bactericidal at concentrations 2 and 4 times the minimum inhibitory concentration (MIC): a reduction of 99.9% in CFU values was generally observed after 6-8 h.

Administration, Oral↗
PubMed2000

Macrolide antibiotics inhibit nitric oxide generation by rat pulmonary alveolar macrophages.

There is evidence that macrolide antibiotics are effective in the treatment of chronic airway inflammatory diseases, probably through actions other than their antibacterial properties. In order to determine whether macrolides affect the nitric oxide-generating system in the respiratory tract, rat pulmonary alveolar macrophages (PAMs) were studied in vitro. The release of NO was assessed by direct measurement with a specific amperometric sensor for this molecule, and the expression of type II NO synthase (NOS) messenger ribonucleic acid (mRNA) was determined by Northern blotting. Incubation of PAMs with lipopolysaccharide from Escherichia coli and recombinant human interferon-gamma caused release of NO, which was accompanied by induction of type II NOS mRNA. The release of NO was reduced by coincubation of cells with the macrolides erythromycin, clarithromycin and josamycin in a concentration-dependent manner, the maximal inhibition being 73+/-10, 81+/-6 and 84+/-9%, respectively, but was not altered by amoxycillin or cefaclor. These macrolides likewise inhibited the induction of type II NOS mRNA, whereas no inhibitory effects were observed with amoxycillin or cefaclor. These results suggest that macrolide antibiotics specifically inhibit type II NO synthase gene expression and consequently reduce NO production by rat pulmonary alveolar macrophages, which might result in attenuation of airway inflammation.

Amoxicillin↗
PubMed2000

Cost-effectiveness of sparfloxacin compared with other oral antimicrobials in outpatient treatment of community-acquired pneumonia.

We examined the cost-effectiveness of sparfloxacin compared with other selected oral antimicrobials in outpatient treatment of community-acquired pneumonia (CAP) using clinical pathway-based decision analysis. Cost estimates were obtained from medical claims databases and Medicare reimbursement schedules. Probability estimates were derived from published clinical trials, the medical literature, and clinical expert opinion. Overall adjusted efficacy rates were 89% for sparfloxacin, 79.4% for azithromycin, 77.8% for clarithromycin, 73% for cefaclor, 70.8% for amoxicillin-clavulanic acid, and 69% for erythromycin. The expected total cost/CAP episode of treatment with sparfloxacin was $216.07 compared with $258.97, $297.08, $345.75, $389.80, and $395.93 for azithromycin, clarithromycin, erythromycin, amoxicillin-clavulanic acid, and cefaclor, respectively. Therapy with sparfloxacin for managing CAP is cost effective-relative to other commonly prescribed antibiotics, resulting in net cost savings.

Administration, Oral↗
PubMed2003

A case of baboon syndrome associated with group a streptococcal infection.

We described a 21-year-old Japanese patient with sore throat, fever, and diffuse erythema on the neck, trunk, and limbs. Erythema markedly appeared on the neck, axillary, antecubital, and popliteal fossae. However, other skin signs of scarlet fever such as red strawberry tongue and linear petechial eruption did not appear. Before his visit to our clinic, he had been diagnosed as pharyngitis and treated with cefaclor 750 mg daily for six days. However, the symptoms did not improve. Oral prednisolone of 20 mg daily rapidly improved all the symptoms. Pharyngeal culture grew Streptococcus pyogenes that was sensitive to cefaclor. Laboratory findings showed elevated serum levels of antibody against streptolysin O. Together with the distribution of erythema, culture of Streptococcal pyogenes, and elevated anti-streptolysin O titer, the diagnosis of baboon syndrome associated with streptococcal infection was made. This seems to be the first report of baboon syndrome due to streptococcal infection.

Adult↗
PubMed2005

Antibacterial activity of glass-ionomer cement containing antibiotics on caries lesion microorganisms.

PURPOSE: To assess the total viable bacteria in infected dentin after sealing with glass-ionomer cement containing 1% metronidazole, 1% ciprofloxacin and 1% cefaclor. METHODS: 40 children were selected, with ages ranging from 4-10 years, with primary teeth with active carious lesions without any pulpal involvement. The patients were divided randomly into two groups in accordance to the glass-ionomer cement used to seal the carious lesions: Group 1 (control, n=20), sealing with conventional glass-ionomer cement; and Group 2 (test, n=20) sealing with glassionomer cement including antibiotics. The infected dentin was collected both before and 24 hours after the sealing of the cavities and, after inoculation in blood agar, all the plates were incubated in containers kept at 37 degrees C for 5 days in an atmosphere of 85% N2, 10% CO2 and 5% H2, for subsequent counting of total viable bacteria. RESULTS: The results were analyzed using the Wilcoxon and Mann-Whitney tests. The glass-ionomer cement with 1% of metronidazole, 1% of ciprofloxacin and 1% of cefaclor showed a significantly greater reduction in microbiota in the infected dentin in comparison to the reduction with the conventional ionomer cement (P< 0.01), with a mean reduction of 98.65% of all viable bacteria. The infected dentin after sealing with glass-ionomer cement with antibiotics showed, using scanning electron microscopy, the presence of bacterial aggregates, intertubular dentin with exposure of collagen fibers, and dentin tubules.

Anti-Bacterial Agents↗
PubMed1979

[The distribution of minimal inhibitory concentrations of recently introduced cephalosporins in multiresistant strains of Escherichia coli, Proteus mirabilis and Klebsiella spec. as revealed by zone sizes of a standardized agar diffusion test (author's transl)].

Strains of a species were divided into two groups according to the number of resistances (less than or equal to 4, greater than or equal to 5) using 10 standard chemotherapeutics regularly examined, the new cephalosporins not being among them. These groups of less than or equal to 4- and greater than or equal to 5-fold resistant strains were compared for each cephalosporin tested (Fig. 1). The most different distributions of zone diameters (of both groups) were seen in Cephalothin, whereas in Cefoxitin and - with little limitations - also in Cefuroxime in the main these distributions did not differ; they covered the same field. The distributions of Cefaclor and Cefamandole took an intermediate position. With respect to the two groups similar observations were made for E. coli, proteus mirabilis and Klebsiella spec. The differences between the two groups were most marked in Klebsiella strains. E. coli exhibited the smallest differences (Fig 1). On the assumption that the distribution of zone diameters reflect that of MIC's it can be concluded that nearly all of the Cefaclor- and Cefamandole-sensitive multiresistant strains have more elevated MIC's than those with only less than or equal to 4 resistances. On the other hand it must not be expected that MIC'S OF Cefoxitin and Cefuroxim are rising in multiresistant strains. It could be demonstrated that the different qualities of the recently introduced cephalosporins revealed in multiresistant strains can be explained by different dependences on mechanisms of Cephalothin-resistance (Fig. 2). This resistance is much more frequent in greater than or equal to 5-fold resistant strains. Recommendations for clinical use derived from these results are discussed.

Cefaclor↗
PubMed1997

[Treatment of lower respiratory tract infections in the elderly].

Sixty outpatients at the age of 65 to 75 years with exacerbated chronic bronchitis were treated with antibiotics: amoxycillin/clavulanic acid (20 patients), cefaclor (20 patients) and ciprofloxacin (20 patients). The treatment course in all the cases was 5 days. Bacteriological tests of the sputum specimens and estimation of the isolate antibiotic susceptibility by the disk diffusion method were applied to all the patients before and after the treatment. 73 per cent of the patients had mixed infection. The microflora mainly included various species of streptococci highly susceptible to the drugs (54 per cent) as well as highly susceptible strains of pneumococci and hemophilic bacilli (33 and 17 per cent respectively). Atypical microflora was detected in 10 per cent of the cases. Pseudomonas aeruginosa strains were isolated in 2 cases. Acinetobacter sp. slightly susceptible only to ciprofloxacin was isolated in 1 case. Citrobacter sp. slightly susceptible to cefaclor and moderately susceptible to ciprofloxacin was detected in 1 case. Enterobacter sp. moderately susceptible only to ciprofloxacin was isolated in 1 case. A positive factor was moderate susceptibility of Proteus mirabilis to all the three drugs. In 24 patients (the average age of 54.7 years) the pharmacokinetics of ofloxacin administered under 2 different regimens was studied. The drug was used in a single dose of 400 mg once a day (group 1) or in a dose of 200 mg twice a day (group II) followed by estimation of the drug concentration in the blood and sputum. The pathogen eradication was stated in 61.5 and 72.7 per cent of the patients in groups I and II, respectively. By the results of the treatment with the use of the above mentioned antibiotics in the elderly patients fluoroquinolones should be considered preferable from the clinical and pharmacoeconomic viewpoints.

Aged↗
PubMed1994

Microbiology and management of chronic maxillary sinusitis.

OBJECTIVE: Assessment of the microbiology and management of patients who suffered from chronic maxillary sinusitis was studied retrospectively. DESIGN: Retrospective analysis of microbiology and antimicrobial therapy of 68 patients who underwent the Caldwell-Luc procedure for chronic sinusitis had not received antimicrobials before surgery and whose cultures showed bacterial growth. SETTING: This study was performed at the Naval Hospital in Bethesda, Md. INTERVENTION: Amoxicillin-clavulanic acid was given to 18 patients, amoxicillin or ampicillin to 25, cefaclor to 17, and erythromycin to eight. RESULTS: A total of 183 isolates (123 anaerobic and 60 aerobic) were recovered. Anaerobic organisms only were recovered from 35 (51%), specimens, and aerobic or facultative bacteria only in 12 (18%), and mixed aerobic and anaerobic flora in 21 (31%). Thirty-four aerobic and anaerobic beta-lactamase-producing bacteria were isolated from 28 patients. The 18 patients who received amoxicillin-clavulanic acid had the most rapid and complete response to therapy, none required a change in therapy, and surgical drainage was required in one case. Of 25 patients who received amoxicillin or ampicillin, eight required a change of therapy due to clinical failure (32%), including three who also had surgical drainage. Of 17 that received cefaclor, five had an antibiotic change (29%), one with surgical drainage. Of the eight who were treated with erythromycin, three needed antibiotic change (38%), two with surgical drainage. Resistant organisms were recovered from most of the patients that required therapeutic change. CONCLUSIONS: These findings indicate the major role of aerobic and anaerobic beta-lactamase-producing bacteria organisms in the polymicrobial etiology of chronic maxillary sinusitis and illustrate the superiority of therapy effective against these bacteria.

Adolescent↗