Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sparfloxacin and levofloxacin were evaluated against 150 Haemophilus influenzae isolates and 149 Neisseria gonorrhoeae isolates in order to define susceptibility testing parameters. Sparfloxacin-susceptible H. influenzae strains were defined as those for which the MICs were < or = 0.25 microgram/ml and the zones were > or = 30 mm, and N. gonorrhoeae susceptible strains were those for which the MICs were < or = 0.03 microgram/ml and the zones were > or = 39 mm (5-micrograms disks). Levofloxacin-susceptible strains of H. influenzae included those for which the MICs were < or = 0.12 microgram/ml and the zones were > or = 32 mm and N. gonorrhoeae susceptible strains were those for which the MICs were < or = 0.12 microgram/ml and the zones were > or = 37 mm (5-micrograms disks). Criteria for a resistant category cannot yet be defined for either quinolone. In multilaboratory studies with different lots of Haemophilus Test Medium, replicate tests with the standard control strain of H. influenzae (ATCC 49247) were evaluated. For sparfloxacin disk tests, the proposed zone size limits were 33 to 42 mm and broth microdilution MIC limits were 0.004 to 0.016 microgram/ml, whereas for levofloxacin tests, zone size limits were 32 to 41 mm and broth microdilution MIC limits were 0.008 to 0.03 microgram/ml. Other multilaboratory studies evaluated tests with supplemented GC agar and N. gonorrhoeae ATCC 49226; for both drugs, zone size limits were 44 to 52 mm and agar dilution MIC limits were 0.004 to 0.016 microgram/ml.
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PMID:Tentative criteria for confirming the in vitro susceptibilities of Haemophilus influenzae and Neisseria gonorrhoeae to two fluoroquinolones (sparfloxacin and levofloxacin), including quality control parameters. 840 59

The more active L-isomer, levofloxacin, of the racemic ofloxacin mixture has been under development for therapeutic use. In this study, we evaluated the activity of ofloxacin, levofloxacin, and D-ofloxacin against the fastidious respiratory tract pathogens Haemophilus influenzae and Moraxella catarrhalis. Levofloxacin was two-fold more active than ofloxacin against H. influenzae (MIC90, 0.015 microgram/ml), and D-ofloxacin was least active (MIC90, 1 microgram/ml). For M. catarrhalis the MIC90 values were 0.03 microgram/ml, 0.06 microgram/ml, and 2 micrograms/ml for levofloxacin, ofloxacin, and D-ofloxacin, respectively. For disk diffusion susceptibility testing, Chocolate Mueller-Hinton agar (CMH) was considered preferable to Haemophilus test medium (HTM) because it supported the growth of all of 105 H. influenzae strains whereas five strains failed to grow on HTM. In addition, the margins of the zones of inhibition were more distinct on CMH and the Haemophilus species strains with elevated fluoroquinolone MICs were readily distinguished. The superior growth on CMH was reflected in a reduction of inhibition zone diameters of 2-3 mm relative to the inhibition zone diameters on HTM. The previously proposed interpretive criteria for the 5 microgram disk diffusion susceptibility test (susceptible at > or = 17 mm) results in complete categorical agreement with the reference microdilution broth method for M. catarrhalis on Mueller Hinton agar and for H. influenzae on HTM and CMH. However, the minimum diameter of the zone of inhibition recorded for a member of the dominant population of either species was considerably greater (25 mm) than 17 mm on any of the media tested.
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PMID:Susceptibility testing interpretive criteria for levofloxacin when testing respiratory pathogens, Haemophilus influenzae and Moraxella catarrhalis. 872 1

Five hundred ninety patients were enrolled in a prospective, multicenter, randomized trial comparing the efficacy and safety of 7 to 14 days of levofloxacin treatment with that of ceftriaxone and/or cefuroxime axetil in the management of community-acquired pneumonia in adults. Patients received either intravenous and/or oral levofloxacin (500 mg once daily) or the comparative agents, parenteral ceftriaxone (1 to 2 g once to twice daily) and/or oral cefuroxime axetil (500 mg twice daily). Erythromycin or doxycycline could be added to the comparator arm at the investigator's discretion. The decision to use an intravenous or oral antimicrobial agent for initial therapy was made by the investigator. Clinical and microbiological evaluations were completed at the baseline, during treatment, 5 to 7 days posttherapy, and 3 to 4 weeks posttherapy. Four hundred fifty-six patients (226 given levofloxacin and 230 administered ceftriaxone and/or cefuroxime axetil) were evaluable for clinical efficacy. Streptococcus pneumoniae and Haemophilus influenzae were isolated in 15 and 12%, respectively, of clinically evaluable patients. One hundred fifty atypical pathogens were identified: 101 were Chlamydia pneumoniae, 41 were Mycoplasma pneumoniae, and 8 were Legionella pneumophila. Clinical success at 5 to 7 days posttherapy was superior for the levofloxacin group (96%) compared with the ceftriaxone and/or cefuroxime axetil group (90%) (95% confidence interval [CI] of -10.7 to -1.3). Among patients with typical respiratory pathogens who were evaluable for microbiological efficacy, the overall bacteriologic eradication rates were superior for levofloxacin (98%) compared with the ceftriaxone and/or cefuroxime axetil group (85%) (95% CI of -21.6 to -4.8). Levofloxacin eradicated 100% of the most frequently reported respiratory pathogens (i.e., H. influenzae and S. pneumoniae) and provided a >98% clinical success rate in patients with atypical pathogens. Both levofloxacin and ceftriaxone-cefuroxime axetil eradicated 100% of the S. pneumoniae cells detected in blood culture. Drug-related adverse events were reported in 5.8% of patients receiving levofloxacin and in 8.5% of patients administered ceftriaxone and/or cefuroxime axetil. Gastrointestinal and central and peripheral nervous system adverse events were the most common events reported in each treatment group. In conclusion, these results demonstrate that treatment with levofloxacin is superior to ceftriaxone and/or cefuroxime axetil therapy in the management of community-acquired pneumonia in adults.
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PMID:A multicenter, randomized study comparing the efficacy and safety of intravenous and/or oral levofloxacin versus ceftriaxone and/or cefuroxime axetil in treatment of adults with community-acquired pneumonia. 930 95

A U.S. surveillance study of antimicrobial resistance in respiratory tract pathogens in the respiratory season (1996-1997) is reported that included 11,368 isolates from 434 institutions in 45 states and the District of Columbia. beta-lactamase was produced by 33.4% of Haemophilus influenzae and 92.7% of Moraxella catarrhalis. Of the 9,190 Streptococcus pneumoniae isolates tested, 33.5% were not susceptible to penicillin (MIC > or = 0.12 microgram/mL), with 13.6% having high-level resistance (MICs > 1 microgram/mL). For H. influenzae, the most active antimicrobials (based on percent of strains susceptible) were levofloxacin (100%) and ceftriaxone (99.9%); the least active were ampicillin (67.2%) and clarithromycin (58.1%). For M. catarrhalis, the most active drugs were amoxicillin-clavulanate, ceftriaxone, and levofloxacin (100%); the least active was ampicillin. The order of the activity of the drugs against S. pneumoniae were levofloxacin (97.3%) > ceftriaxone (87.1%) > amoxicillin-clavulanate (81.7%) = clarithromycin (80.9%) > cefuroxime (74.5%) > penicillin (66.5%). The activity of the beta-lactams and clarithromycin against isolates of S. pneumoniae was closely associated with the resistance to penicillin. Levofloxacin was more active against S. pneumoniae overall, because it exhibited no cross-resistance. These data indicate that the incidence of beta-lactamase production in H. influenzae (33.4%) and M. catarrhalis (92.7%) is similar to other recent studies, and that the incidence of penicillin-intermediate and -resistant S. pneumoniae is increasing, particularly the high-level penicillin-resistant (MICs > 1 microgram/mL) strains, which were often multi-resistant.
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PMID:Surveillance of antimicrobial resistance in Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in the United States in 1996-1997 respiratory season. The Laboratory Investigator Group. 945 82

A total of 1,116 clinically isolated strains belonging to Staphylococcus aureus (200), Staphylococcus epidermidis (200), Streptococcus pneumoniae (20), Escherchia coli (200), Klebsiella spp. (177), Serratia marcescens (22), Pseudomonas aeruginosa (224), Haemophilus influenzae (35) and Salmonella (38) from the Department of Infectious Diseases, La Sapienza University in Rome (Italy) were tested against three fluoroquinolones (ofloxacin, ciprofloxacin and levofloxacin) and 10 other antibiotics (augmentin, ampicillin, cefaclor, cefixime, cefotaxime, cotrimoxazole, gentamicin, minocycline, oxacillin and vancomycin). Fluoroquinolones inhibited essentially about 100% of H. influenzae, Salmonella and S. pneumoniae, more than 75% of Staphylococcus including methicillin-resistant strains, and about 90% of Enterobacteriaceae and 50% of P. aeruginosa. Minimal inhibitory concentration values ranged from < 0.015 to > 32 micrograms/ml for Klebsiella, S. aureus and epidermidis, E. coli and P. aeruginosa; from < 0.015 to 2 micrograms/ml for Salmonella; from 0.03 to 16 micrograms/ml for Serratia; from < 0.015 to 1 microgram/ml for Haemophilus; and from 0.5 to 2 micrograms/ml for S. pneumoniae. Levofloxacin and to a lesser extent ofloxacin and ciprofloxacin, generally exhibited a greater activity than the other agents against both Gram-positive and Gram-negative bacteria. Regarding the distribution of resistant strains in Italy, we found a peculiar pattern of resistance as far as E. coli and P. aeruginosa were concerned. Quality control parameters are also summarized. S. epidermidis resulted as a new emergent pathogen especially in immunocompromised patients and its level of sensitivity has been modified over the last few years. In fact, the percentage of resistant strains to antibiotics or the percentage of methicillin-resistant isolates (in our study 35%), has gradually increased. Levofloxacin and ofloxacin showed good activity against staphylococcal strains compared with the majority of other antibiotics. These results suggest that the newer quinolones are promising antimicrobial agents for various infections.
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PMID:Antimicrobial activity of fluoroquinolones and other antibiotics on 1,116 clinical gram-positive and gram-negative isolates. 982 30

By an agar dilution method, the antimicrobial susceptibilities of antral sinus puncture isolates were studied. Pneumococci were generally susceptible to amoxicillin, azithromycin, and clarithromycin, but 17% of pneumococcal isolates were resistant to cefuroxime. Haemophilus influenzae isolates were resistant to amoxicillin and clarithromycin. beta-Lactamase production occurred in 69% of Prevotella species. One-third of Peptostreptococcus magnus isolates were resistant to azithromycin and clarithromycin. Cefuroxime had limited activity against Prevotella species and P. magnus. Levofloxacin was active against most isolates except peptostreptococci. Amoxicillin-clavulanate was active against all isolates, with the MIC at which 90% of the isolates were inhibited being < or = 1 microgram/ml.
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PMID:Comparative in vitro activities of amoxicillin-clavulanate against aerobic and anaerobic bacteria isolated from antral puncture specimens from patients with sinusitis. 1004 96

Levofloxacin is the first fluoroquinolone with enhanced activity against Streptococcus pneumoniae to be released in Canada. In vitro, it is active against more than 99% of isolates of S pneumoniae, even those resistant to penicillin. It is also active against respiratory pathogens such as Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella species. When given orally, bioavailability is greater than 99%, and the drug is highly concentrated in lung tissue and macrophages. Drug levels are compatible with once-daily dosing. In a large clinical trial, levofloxacin has shown clinical and microbiological superiority compared with ceftriaxone/cefuroxime. The characteristics of levofloxacin - high oral bioavailability, long duration of effect, activity against key respiratory pathogens and high tolerability - suggest that it will be a useful drug in the treatment of community acquired pneumonia.
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PMID:Levofloxacin in the treatment of community acquired pneumonia. 1020 32

The in-vitro activity of levofloxacin was studied against 10 beta-lactamase-negative and 93 beta-lactamase-positive Moraxella catarrhalis isolates, and 65 beta-lactamase-negative and 35 beta-lactamase-positive Haemophilus influenzae isolates. The MICs of levofloxacin were determined by agar dilution on Mueller-Hinton agar (with the addition of 5% horse blood for M. catarrhalis) or on Haemophilus Test Medium for H. influenzae, and were compared with those of ofloxacin, ciprofloxacin and sparfloxacin, as well as pefloxacin and D-ofloxacin for M. catarrhalis. The fluoroquinolones showed similar activity against isolates of H. influenzae and M. catarrhalis, irrespective of beta-lactamase production. Levofloxacin (MIC50/90 0.06 mg/L) was 64 times more active against M. catarrhalis than D-ofloxacin (MIC50/90 4/8 mg/L) and twice as active as ofloxacin (MIC50/90 0.125 mg/L). Ciprofloxacin had an MIC50/90 of 0.03/0.06 mg/L and sparfloxacin showed an MIC50/90 of 0.015 mg/L against M. catarrhalis irrespective of the resistance phenotype of the isolates. Against H. influenzae, levofloxacin was twice as active as ofloxacin (MIC90 values 0.03 mg/L versus 0.06 mg/L), while the MIC90s of ciprofloxacin and sparfloxacin were both 0.015 mg/L. Our results therefore suggest that levofloxacin has potential for treating respiratory tract infections caused by H. influenzae and M. catarrhalis.
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PMID:In-vitro activity of levofloxacin, a new fluoroquinolone: evaluation against Haemophilus influenzae and Moraxella catarrhalis. 1040 33

The objective of this study was to evaluate the activity of the fluoroquinolone, levofloxacin, against hospital isolates of bacteria. MICs of levofloxacin were determined for 2154 strains by agar dilution. Breakpoints for susceptibility testing were calculated using the agar diffusion technique with 5 micrograms discs. The activity of levofloxacin against nalidixic acid- and pefloxacin-susceptible Enterobacteriaceae (n = 668) was higher (MIC50/90 0.06-0.12 mg/L) than previously reported for ofloxacin. As seen with other fluoroquinolones, this activity was reduced against nalidixic acid-resistant and pefloxacin-intermediate and -resistant strains (MIC 1-8 mg/L). MICs for Pseudomonas aeruginosa (n = 104) were between 0.12 and 128 mg/L. Levofloxacin had good activity against nalidixic acid- and pefloxacin-susceptible Acinetobacter baumannii (n = 12; MIC 0.06-0.25 mg/L), but the activity was reduced against nalidixic acid- and pefloxacin-resistant strains (n = 80; MIC 1-32 mg/L). Haemophilus influenzae (n = 70), Haemophilus parainfluenzae (n = 47) and Moraxella catarrhalis (n = 64) were inhibited by low concentrations of levofloxacin (MICs 0.016-0.03 mg/L, 0.03-0.12 mg/L) and 0.03-0.12 mg/L, respectively). Clostridium perfringens (n = 23; MIC 0.25-1 mg/L) was more susceptible than Bacteroides fragilis (n = 60; MIC 0.5-4 mg/L). Levofloxacin showed superior activity compared with ofloxacin against methicillin-susceptible staphylococci (n = 107; MIC 0.03-0.5 mg/L); the resistant strains (MICs 2-32 mg/L) were usually also resistant to methicillin. Levofloxacin was less effective against enterococci (n = 105; MIC 1-32 mg/L), but streptococci (n = 192) and pneumococci (n = 129), including 58 penicillin-non-susceptible strains, were inhibited by low concentrations (MICs 0.5-2 mg/L). According to the regression curve, zone diameters were usually 20-22 mm, 17-19 mm and 15-16 mm for MICs of 1, 2 and 4 mg/L, respectively. In conclusion, this study, performed on a large number of strains, confirms the superior anti-bacterial activity of levofloxacin compared with ofloxacin, especially against pathogens isolated from respiratory tract infections.
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PMID:In-vitro antibacterial activity of levofloxacin against hospital isolates: a multicentre study. 1040 37

The aim of this study was to compare the bactericidal efficacy of levofloxacin and ofloxacin against Streptococcus pneumoniae at different dosage regimens for both agents. An in-vitro pharmacodynamic model was used. Levofloxacin kinetics of 500 mg, administered od or bd, were compared with ofloxacin kinetics of 400 mg od or bd. Killing by 3 log10 (99.9%) was achieved up to an MIC of 0.5 mg/L (500 mg od) or 1 mg/L (500 mg bd). For levofloxacin killing of S. pneumoniae was unimpaired in mixed cultures with Haemophilus influenzae. For ofloxacin, killing by 2 log10 was achieved up to an MIC of 0.5 mg/L for 400 mg od and up to an MIC of 1 mg/L for 400 mg bd. Killing by 3 log10 was not achievable by 400 mg od, but was achieved up to an MIC of 0.5 mg/L for 400 mg bd. Killing of S. pneumoniae with identical MICs of levofloxacin was not influenced by their susceptibility to penicillin G. These data, together with the two-fold higher activity of levofloxacin in comparison with ofloxacin, indicate good therapeutic perspectives for levofloxacin over ofloxacin in the treatment of S. pneumoniae infections.
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PMID:Pharmacodynamics of levofloxacin and ofloxacin against Streptococcus pneumoniae. 1040 43


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