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)

The attainable inhibitory ratios (AR) for oral antibiotics were calculated by using literature reports of concentrations attained in respiratory secretions for amoxicillin-clavulanic acid (AMX/CA), ofloxacin (OFL), L-ofloxacin (L-OFL), cefuroxime (CEFU), ciprofloxacin (CIP), and enoxacin (ENO), and using microdilution minimum inhibitory concentration data of these antimicrobials against the common bacterial respiratory pathogens. AR of each antibiotic against the pathogens was expressed as multiples of the MICs achieved at the respiratory site. Bacteria tested included Staphylococcus aureus, group-A and group-B streptococci, Viridans streptococci, Streptococcus pneumoniae, Brahamella catarrhalis, Klebsiella pneumoniae, Eikenella corrodens, Haemophilus influenzae, H. parainfluenzae, Pseudomonas aeruginosa, and Legionella pneumophila. The antimicrobials with the narrowest spectrum of activity were amoxicillin-clavulanic acid and cefuroxime which had high attainable inhibitory ratios only against Gram-positive cocci. Ofloxacin and L-oflaxacin were among the quinolones with the highest overall ARs against respiratory pathogen, including, L. pneumophila, H. influenzae, and B. catarrhalis. All agents showed no, or inadequately low ARs for P. aeruginosa.
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PMID:A comparison of antimicrobial activity of ofloxacin, L-ofloxacin, and other oral agents for respiratory pathogens. 157 39

We made an open, noncomparative evaluation of ofloxacin, 400 mg orally bid for 10 days, in 98 subjects with community-acquired pneumonia or pathogen-confirmed bronchitis. Thirty-nine (40%) of the subjects were treated in the hospital and 59 (60%) were treated as outpatients. The mean age of those treated was 56.2 years; 73 (74%) of the subjects either were more than 60 years old or had a history of chronic obstructive pulmonary disease, or both. There were 95 organisms initially isolated in sputum, aspirate, or lavage fluid; all were susceptible to ofloxacin, and none acquired resistance during therapy. Haemophilus influenzae was the most common pathogen (19 isolates), followed by Streptococcus pneumoniae (18) and Staphylococcus aureus (10). Clinical responses included cure in 70 patients (71%), improvement in 26 (27%), and failure in two (2%). After 10 days of therapy, pathogens persisted in two cases; in one case, Streptococcus salivarius was isolated, though it remained susceptible to ofloxacin, and in the other, Klebsiella pneumoniae was accompanied by superinfection due to a resistant strain of Serratia marcescens. We included in this study three confirmed cases of atypical pneumonia successfully treated with ofloxacin, two of them due to Mycoplasma pneumonia and one to Legionella pneumophila. Ofloxacin was well tolerated. Our data indicate that ofloxacin is effective and safe as specific and empiric treatment for many lower respiratory tract infections.
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PMID:Oral ofloxacin therapy for lower respiratory tract infection. 173 27

Ofloxacin is highly active against common respiratory pathogens including Haemophilus influenzae and Branhamella catarrhalis and has clinically applicable activity against Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa. Sputum, lung tissue and bronchial mucosal concentrations of ofloxacin equal or, in most cases significantly exceed the MICs of such pathogens. These in vitro attributes are reflected in the results of the worldwide ofloxacin clinical trial program which achieved overall response rates of 98% in lower respiratory tract infections, 83% in pneumonias and 87% to 95%, in open and comparative studies respectively, in patients with acute exacerbations of chronic bronchitis (CB). Overall bacterial eradication rates ranged from 70% for pneumococci and 84.5% for B. catarrhalis to 88.5% for H. influenzae. In lower respiratory infection ofloxacin gave equal or superior clinical results to amoxycillin or erythromycin therapy together with an overall bacterial eradication rate of 100%. Clinical results comparable with standard agents were also obtained in pneumonia, cure rates ranging from 77-89% at various dosages. Eradication rates proved greatest for H. influenzae (92%) and were satisfactory for Klebsiella spp. (80%), although less so for pneumococci (73%). Bacteriological eradication rates in acute exacerbations of chronic bronchitis ranged from 68% for pneumococcal infections, to 85% in B. catarrhalis and 94% in H. influenzae infections. Ofloxacin compared favourably with pivampicillin, co-trimoxazole and doxycycline clinically. A daily oral ofloxacin dose of 400 mg produced a good clinical response in 92% of patients or more. The available clinical data therefore substantially confirm the claim of ofloxacin to offer an effective alternative in many forms of acute bacterial respiratory infection, especially where H. influenzae and B. catarrhalis are involved.
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PMID:Overview of experience with ofloxacin in respiratory tract infection. 221 24

The literature on the penetration of ofloxacin from blood to respiratory tissue and secretions in patients is reviewed. In patients with acute purulent exacerbations of chronic bronchitis ofloxacin has a Cmax value in sputum of 2.7 mg/l after a 400 mg oral dose, 6.1 mg/l after 600 mg and 6.3 mg/l after 800 mg. Penetration from blood to sputum varied from 80 to 100%. The concentration of ofloxacin in bronchial aspirate, 1 to 6 h after a single oral dose of 400 mg, varied between 1.1 and 4.5 mg/l. The ratio between simultaneous mean bronchial aspirate and serum concentrations ranged between 0.53 in the second hour and 0.92 in the fourth hour. Ofloxacin concentrations in bronchoalveolar lavage fluid following an oral dose of 200 mg twice daily for at least four days amounted to 8.3 mg/l with a corresponding serum concentration of 1.7 mg/l five hours after the last dose. The distribution ratio between lavage fluid and serum was 4.9. The lung tissue penetration of ofloxacin after a dosage of 200 mg twice daily, reached a mean tissue plasma concentration ratio of 3.5 +/- 0.4 for healthy tissue and 3.9 +/- 0.4 for diseased tissue. Ofloxacin reaches high intracellular concentrations in polymorphonuclear leucocytes, alveolar macrophages, epithelial cells and fibroblasts. It is likely that these concentrations will have a sustained inhibitory and bactericidal activity against most potential respiratory pathogens including: Haemophilus influenzae, Branhamella catarrhalis, Gram-negative bacilli, Staphylococcus aureus, Legionella pneumophila, Chlamydia spp. and Coxiella burnetti.
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PMID:Ofloxacin concentrations in tissues involved in respiratory tract infections. 228 91

In the past decade, significant progress has been made in understanding structure-function relationships of the new quinolones, which have a N-1-substituted, 1,4-dihydro-4-oxo-pyridine-3-carboxylic acid moiety as the basic nucleus. Modification of the groups affixed to positions C-6, C-7, and C-8 has made a major change in the antimicrobial activity, pharmacokinetic, and metabolic properties of the quinolones as have changes in the moieties affixed to the N-1 nitrogen. The new quinolones have a carboxyl group at position 3 and a keto group at C-4. The presence of a fluorine atom at C-6 enhances the deoxyribonucleic acid (DNA) gyrase inhibitory activity as well as the ability of the compounds to inhibit staphylococci. Position C-7 has been one of the most modified sites. Addition of a piperazinyl group markedly increased gram-positive activity, primarily antistaphylococcal activity; lowered the minimal inhibitory concentrations against Enterobacteriaceae, Haemophilus spp., and Neisseria spp.; and added activity against Pseudomonas aeruginosa compared with nalidixic acid. Methyl derivatives of the piperazine group or of the pyrroles have longer half-lives than do unsubstituted moieties. At the N-1 position, a cyclopropyl group appears to be most potent with respect to minimal inhibitory concentrations against Enterobacteriaceae and Pseudomonas. Ofloxacin is unique in that it has an oxygen substituted at C-8 with the substituent part of the ring system formed by fusion to the N-1 position. This has produced excellent in vitro activity against gram-positive species comparable with that of ciprofloxacin, excellent activity against the Enterobacteriaceae, and antipseudomonal activity superior to agents with an ethyl substitution at position N-1. The oxazine ring of ofloxacin provides excellent oral absorption with virtually 95 percent bioavailability; this modification also has prevented metabolism and has provided a long half-life of seven to eight hours.
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PMID:Chemical evolution of the fluoroquinolone antimicrobial agents. 255 62

The cerebrospinal fluid (CSF) penetration of ofloxacin given orally or or intravenously was studied in cancer patients without meningitis. Each patient was assigned to a different sampling time to assess the relation between time and penetration. Ofloxacin was measured in serum and CSF by high-pressure liquid chromatography and bioassay. In addition, the bactericidal titers were measured in CSF and serum against a set of relevant bacteria. Concentrations measured by high-pressure liquid chromatography and bioassay were well correlated. Peak concentrations in CSF (0.4 to 1 microgram/ml) were observed 2 to 4 h after infusion or oral administration. Peak concentrations in serum were observed just after infusion (2 to 3.5 micrograms/ml) or 1 to 2 h after oral administration (1.7 to 4 micrograms/ml). Measured bactericidal titers were well correlated with the titers expected from the MBC and concentration. High CSF bactericidal titers were observed against Neisseria meningitidis, Haemophilus influenzae, and Escherichia coli, whereas low or no bactericidal titers were obtained against Staphylococcus aureus, Listeria monocytogenes, and Streptococcus pneumoniae.
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PMID:Concentrations of ofloxacin in serum and cerebrospinal fluid of patients without meningitis receiving the drug intravenously and orally. 258 41

The fluoroquinolone, ofloxacin, exhibits a broad antibacterial spectrum. Based on our data and a review of the literature, ofloxacin inhibited essentially 100 percent of staphylococci, including oxacillin-resistant strains, Haemophilus influenzae, Neisseria spp. and Branhamella catarrhalis. Ninety-five percent of Enterobacteriaceae were susceptible to ofloxacin. Pseudomonas aeruginosa and enterococci were less susceptible: 79 and 63 percent, respectively, were susceptible (minimal inhibitory concentration [MIC], less than or equal to 2.0 micrograms/ml); 15 and 25 percent, respectively, were intermediate (MIC, 4 micrograms/ml); 3 and 6 percent, respectively, were resistant (MIC, more than or equal to 4 micrograms/ml). Clostridium spp., including Clostridium difficile, were resistant to ofloxacin, but other anaerobic species, including the Bacteroides fragilis group (over 90 percent) were either susceptible or intermediate to ofloxacin. Ofloxacin is bactericidal; minimal bactericidal concentrations of ofloxacin rarely exceed the MICs by one doubling concentration. A modest inoculum effect has been observed with ofloxacin: MICs with inocula of 10(7) colony-forming units/ml are often two- to fourfold higher than those with inocula of 5 x 10(5) colony-forming units/ml. Susceptible organisms exposed serially to increasing concentrations of nalidixic acid developed increasing resistance to not only nalidixic acid, but also to all other quinolones, including ofloxacin. Correlations of disk diffusion inhibitory zone diameters using the 5-micrograms ofloxacin disk with ofloxacin MICs have been performed, and the disk diffusion zone diameter breakpoints recommended are: susceptible, greater than or equal to 16 mm; intermediate, 13 to 15 mm; resistant, less than or equal to 12 mm. Quality control parameters also are summarized.
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PMID:In vitro antimicrobial activity and susceptibility testing of ofloxacin. Current status. 269 Jun 14

Ninety-one patients with community-acquired lower respiratory infections were treated orally in a comparative 10-day trial of ofloxacin versus amoxicillin or erythromycin. Approximately one-half of the patients had no major underlying disease and the other half had some form of chronic lung disease. Pneumonia was present in 31 percent of the patients and the remainder had purulent bronchitis. Bacterial pathogens were recovered from 60 percent of the patients, with Haemophilus influenzae (33 isolates) and Streptococcus pneumoniae (16 isolates) being the most common. Ofloxacin was found to be a safe, well-tolerated therapeutic agent, which was as effective clinically as amoxicillin or erythromycin and with an advantage of less frequent administration. Ofloxacin was more effective than amoxicillin (90 percent versus 75 percent; p = 0.05) in elimination of pathogenic bacteria from lower airway cultures. Caution should be exercised in the use of ofloxacin, at least in short-term treatment regimens, with anaerobic pulmonary infections; additional information is needed for S. pneumoniae given the relatively high minimal inhibitory concentrations for this species.
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PMID:Ofloxacin in community-acquired lower respiratory infections. A comparison with amoxicillin or erythromycin. 269 Jun 20

The antibacterial activity of ofloxacin against Enterobacteriaceae, Pseudomonas aeruginosa, Haemophilus influenzae, Branhamella catarrhalis, and Neisseria gonorrhoeae was comparable to norfloxacin and enoxacin, and far exceeded the activity of pipemidic acid and nalidixic acid. The activity of ofloxacin was two to eight times less than that of ciprofloxacin. Ofloxacin was more active against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Acinetobacter spp., Legionella spp., and Bacteroides fragilis, than norfloxacin, enoxacin, pipemidic acid and nalidixic acid, and the activity of ofloxacin was comparable to that of ciprofloxacin. Ofloxacin was two to seven times more effective than norfloxacin in systemic infections in mice with S. aureus, Escherichia coli, Serratia marcescens and P. aeruginosa. Ofloxacin strongly inhibited DNA supercoiling activity of DNA gyrase purified from E. coli KL-16. There is a parallel relationship between antibacterial activity of ofloxacin and its inhibitory action against DNA gyrases from ofloxacin-susceptible and ofloxacin-resistant clinical isolates of E. coli. These results indicate that the high bactericidal action of ofloxacin and the related new quinolone agents can be explained by their potent inhibitory activities against DNA gyrase in bacterial cells.
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PMID:Antibacterial activity of ofloxacin and its mode of action. 302 66

The in-vitro activities of enoxacin and ofloxacin were compared with that of the other new 4-quinolone, ciprofloxacin. All three compounds were highly active against Enterobacteriaceae, Haemophilus influenzae and Neisseria gonorrhoeae (MICs mostly less than 1 mg/l). The other Gram-negative aerobes tested were in general less susceptible, though for Acinetobacter and Pseudomonas species (including aeruginosa) MICs seldom exceeded 8 mg/l. Ofloxacin and ciprofloxacin were more active against Gardnerella vaginalis (MICs 0.5-2 mg/l) than was enoxacin (MICs 8-32 mg/l). Staphylococci were susceptible to ofloxacin (MICs 0.12-1 mg/l) and enoxacin (MICs 0.5-2 mg/l) as well as to ciprofloxacin. Streptococci also were mostly sensitive to the compounds though the MICs of enoxacin (4-64 mg/l) were noticeably higher than those of ofloxacin (1-4 mg/l). Anaerobes were in general susceptible though, as with streptococci, ofloxacin, with activity similar to that of ciprofloxacin, was more active than enoxacin. Variants of Enterobacteriaceae with reduced susceptibility were readily selected in the laboratory with either enoxacin or ofloxacin as the selective agent. The MICs of all the 4-quinolones were usually increased four- to 16-fold for these strains; they could therefore be regarded as remaining susceptible to the newer compounds.
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PMID:The in-vitro activities of enoxacin and ofloxacin compared with that of ciprofloxacin. 315 12


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