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At least 1,099 records · Page 61Linked to original sources
PubMed2003

The effectiveness of omeprazole versus lansoprazole along with amoxicillin and clarithromycin in Turkish population with duodenal ulcer.

AIM: To compare the effectiveness of omeprazole versus lansoprazole with amoxicillin and clarithromycin in the Turkish populations with duodenal ulcer. METHODS: Helicobacter pylori positive 108 patients with active duodenal ulcer randomized double blindly into 2 groups. In the group of omeprazole, amoxicillin and clarithromycin (OAC), 54 patients; 34 male, 20 female, average age (+/-SD) 43.89+/-11.77 years. Omeprazole was given 20 mg b.i.d, half an hour before meals for 14 days and then 20 mg preceeding breakfast for 6 weeks along with 1 g amoxicillin and 500 mg clarythromycin b.i.d. for both antibiotics for 14 days while lansoprazole 30 mg b.i.d. was administered half an hour preceeding food intake for 14 days and then 30 mg prebreakfast for 6 weeks with concordant 1 g b.i.d. amoxicillin and clarythromycin 500 mg, b.i.d. for 14 days in the group of lansoprazole with amoxicillin and clarithromicin (LAC) (54 patients; 31 male, 23 female, average age (+/-SD) 40.85+/-12.80 years. The patients were evaluated in clinical terms and by endoscopic parameters for healing, H. pylori eradication and drug side effects before and after 8 weeks of treatment. RESULTS: There were no significant differences in age, sex and smoking between the 2 groups (p=0.20, p=0.56, p=0.85), respectively. In the LAC group, the ulcer healing rate was 94.4% (51 out of 54 patients). H. pylori was eradicated in 49 patients out of 54 (90.7%). The H. pylori eradication rate was 89.7% (26 out of 29) among the smokers. In the OAC group the ulcer healing rate was 90.7% (49 out of 54 patients). H. pylori was eradicated in 43 patients out of 54 (79.6%). The H. pylori eradication rate was 80.0% (24 out of 30 patients) among the smokers. There was no statistical difference between the 2 groups for ulcer healing (p=0.72). There was also no statistical difference for H. pylori eradication between the LAC and OAC groups (p=0.10). Although mild side effects were observed in both groups, there was no indication for stopping the therapy. CONCLUSIONS: This study has shown that the 2 regimens (LAC and OAC) are highly effective in healing duodenal ulcers and eradicating H. pylori. Lansoprazole does not appear to have a significant advantage over omeprazole either in ulcer healing or in H. pylori eradication. Both lansoprazole and omeprazole are well tolerated, but with mild adverse effects.

Journal Article↗
PubMed2026

Dual roles of genes required for intrinsic resistance to clarithromycin in evasion of killing by serum complement in Haemophilus influenzae.

Macrolide antibiotics are commonly prescribed to treat Haemophilus influenzae respiratory tract infections. Studies have primarily focused on emerging H. influenzae strains with acquired macrolide resistance, while the bacterium's intrinsic resistance to antibiotics has been underexamined. Here, we used a genome-wide approach of transposon insertion-site sequencing to screen an H. influenzae mutant library grown in sub-inhibitory doses of the macrolide antibiotic clarithromycin (CLR) to identify 33 genes involved in intrinsic CLR resistance. Almost half of these genes are also needed for survival in the mouse lung. We focused on candidate genes necessary for both intrinsic macrolide resistance and lung survival. Two of these genes affect the outer-membrane composition of H. influenzae, orfH and omp26. Deletions of these genes in Rd and nontypeable H. influenzae clinical isolates, Hi375 and NT127, conferred sensitivity to CLR and polymyxin B and increased membrane permeability to ethidium bromide (EtBr). The omp26 mutant was sensitive to killing by human serum. Deletions of orfH or omp26 in an acrR mutant strain overexpressing a multidrug efflux pump abrogated resistance of the acrR mutant to CLR and restored permeability to EtBr. Thus, deletion of these genes not only mitigates the effects of an acquired resistance mechanism but also remarkably overrides it. Complementation of these deletion mutations restored CLR resistance and decreased permeability to EtBr. Our results indicate that the subset of genes with dual roles in intrinsic resistance and host lung survival may provide potential novel combination antimicrobial therapeutic targets.

Animals↗
PubMed2005

Effectiveness of amoxicillin, azithromycin, cefprozil and clarithromycin in the treatment of acute otitis media in children: a population-based study.

UNLABELLED: Population-based studies may give results different from randomized clinical trials assessing the efficacy of antibiotics. OBJECTIVE: To determine the effectiveness of amoxicillin, azithromycin, cefprozil and clarithromycin in the treatment of acute otitis media (AOM) in children. METHODS: Using Quebec Health Insurance databases (RAMQ), we selected a cohort of children aged < or = 6 years, with a first episode of AOM between 1999 and 2002. The index AOM was defined as a medical service claim with a diagnosis of AOM and an antibiotic dispensation in the following 72 hours. Failures were defined as a new antibiotic dispensation, a hospitalization or outpatient visit for complications related to AOM in the 30 days after the index AOM. Data were analyzed using logistic regression. RESULTS: Overall, 12,693 failures occurred among 60,513 first episodes of AOM. Azithromycin was the only antibiotic that was associated with a decreased risk of failure overall, when compared to amoxicillin (OR 0.88, 95% CI: 0.82, 0.94). However in the first 3 days of treatment (n = 680), azithromycin was more associated with treatment failure (OR 1.6, 95% CI: 1.3, 2.0). Compared to amoxicillin, post-therapy failures (n = 9387) were more likely to occur with cefprozil (OR 1.2, 95%CI: 1.2, 1.3) but were less with azithromycin (OR 0.8 95% CI: 0.8, 0.9). CONCLUSIONS: Azithromycin had the lowest risk of failure 30 days after the onset of treatment but an increased risk of failure during the first few days of treatment. Amoxicillin remains an effective first-line drug for treating first AOM episodes.

Acute Disease↗
PubMed1997

Patient factors that predict failure of omeprazole, clarithromycin, and tinidazole to eradicate Helicobacter pylori.

Omeprazole (20 mg od/b.d.), clarithromycin (250 mg b.d.) and tinidazole (500 mg b.d. for 7 days) [OCT] is an effective regimen against Helicobacter pylori. However, treatment fails in 5%-10% of patients and the reasons for this are not clear. We investigated patient factors that independently predicted failure of this regimen. H. pylori-positive patients were prescribed OCT and the success of treatment was evaluated by the 13C-urea breath test at least 4 weeks after completion of therapy. Patients were prospectively interviewed on past medical history of peptic ulcer and H2-receptor antagonist (H2RA) pre-treatment, smoking history, and alcohol intake. Data were also collected on age, gender, and endoscopic diagnosis to determine factors predicting failure of OCT. H. pylori eradication was achieved in 238 of 273 patients [87%-95% confidence intervals (CI), 83%-91%]. Age, alcohol intake, past medical history of peptic ulcer and peptic ulcer at endoscopy were not independently associated with treatment failure. H. pylori eradication with OCT was less successful in women (P = 0.02), in patients who had received H2RA pre-treatment (P = 0.02), and in smokers (P = 0.02) when evaluated by multiple logistic regression. These findings indicate that OCT is less effective in smokers and in patients who receive H2RA pre-treatment suggesting that these agents should be avoided, if possible, before the patient commences therapy. H. pylori eradication was less successful in women; this result needs further evaluation.

Adult↗
PubMedDate not supplied

Comparative pharmacodynamics of clarithromycin and azithromycin against respiratory pathogens.

The differences between the antibacterial activities of new macrolides such as clarithromycin (CLA) and azithromycin (AZI) against common respiratory tract pathogens are only minor. However, CLA and AZI constitute macrolides with extremely different pharmacokinetic profiles. This constellation presents an opportunity to evaluate the effect of the pharmacokinetic profile on antibacterial kinetics comparatively. In a pharmacodynamic model simulating the dynamics of serum concentrations in bacterial cultures, both CLA and AZI demonstrate bactericidal activity at concentrations reached in human blood at recommended dosages (CLA 250 mg b.i.d., AZI 500 mg o.i.d.). Bactericidal activity of CLA against the variety of pathogens included is superior to that of AZI in the rate and the extent of killing in this model. These results are considered to correlate with the antibacterial effect of macrolides in vivo in cases where pathogens enter the blood stream. Furthermore, mutants with susceptibility reduced between 8 and 16 times in relation to the initial strain of all strains having an initial minimal inhibitory concentration (MIC) < or = 0.25 mg/l, are selected during exposure to AZI, but not to CLA. The pharmacokinetic profiles of CLA and AZI thus strongly influence their antibacterial effect in the pharmacodynamic model, allowing both higher bactericidal activity and greater reduction of the risk of selection of resistant mutants with CLA than with AZI. As a whole, the pharmacodynamics of these macrolides are determined more by the proportion of the MICs to the maximum serum concentration than by the relation of the MICs to the area under the curve.

Anti-Bacterial Agents↗
PubMed1994

Development of resistance to macrolide antibiotics in an AIDS patient treated with clarithromycin for Campylobacter jejuni diarrhea.

In an AIDS patient with diarrhea, identical isolates of Campylobacter jejuni susceptible and, later, resistant to macrolide antibiotics were isolated from feces before and after treatment with clarithromycin. Results of rRNA gene restriction analysis and serotyping suggest that development of resistance rather than simultaneous infection with a susceptible and a resistant strain was responsible for this phenomenon. This is the first report of in vivo development of resistance by Campylobacter jejuni in a patient treated with a macrolide for Campylobacter jejuni infection.

Acquired Immunodeficiency Syndrome↗
PubMed2004

High level of resistance to metronidazole and clarithromycin in Helicobacter pylori isolated from pediatric patients in Poland (1997-2001).

Resistance to metronidazole (Met), clarithromycin (Cla) and amoxycillin (Amo) was examined using H. pylori isolates from child patients before and after treatment in the period 1997-2001. The rate of Met and Cla resistance before treatment was 35.2 and 8.6%, respectively. Six weeks after treatment 48.4% of the isolated strains were resistant to Met and 17.6% to Cla. The highest rate of resistance to both antibiotics was determined in 2001 (before treatment, 46 and 15%, respectively, and after treatment, 57.8 and 26.3%, respectively). All the strains were susceptible to Amo. Strains resistant to Met were detected more frequently in girls than in boys.

Adolescent↗
PubMed2005

Evaluation of in-vitro dissolution and in-vivo absorption for two different film-coated pellets of clarithromycin.

The aim of this study was to compare two formulations of film-coated pellets containing clarithromycin after single oral dose study in healthy male volunteers. Two formulations with different coating polymers were prepared: formulation-1 (F-1) was prepared by incorporating three kinds of pH-dependent gradient-release coated pellets into capsules and formulation-2 (F-2) was prepared by coated with an insoluble semiosmotic film. Release profiles of film-coated pellets were evaluated using paddle method under different conditions. Pharmacokinetic profiles of these formulations were obtained in three healthy male volunteers and compared to commercially available immediate release (IR) tablets. The relative bioavailability based on the AUC0-24h was found to be 96.2% and 58.7% for F-1 and F-2 compared with IR, and the Tmax was delayed.

Anti-Bacterial Agents↗
PubMed2005

Development of a highly sensitive method for detection of clarithromycin-resistant Helicobacter pylori from human feces.

Gastric infection of clarithromycin (CAM)-resistant Helicobacter pylori is one of the major causes of failure to eradicate this organism. A noninvasive and useful method for the detection of CAM-resistant H. pylori from human feces by restriction fragment length polymorphism (RFLP)-nested polymerase chain reaction (PCR) targeting the mutation of the 23S rRNA gene that confers CAM-resistance in H. pylori was developed in this study. Our nested PCR method detected DNA of H. pylori in feces with high sensitivity and specificity compared with both an enzyme-linked immunoadsorbent assay (ELISA) of H. pylori in feces and the isolation of H. pylori from gastric biopsy. Furthermore, the results of mutation analysis of the H. pylori 23S rRNA gene amplified from feces completely correlated with both that of the H. pylori 23S rRNA gene amplified from the isolates of gastric biopsy and the susceptibility of H. pylori isolates to CAM. Therefore, our results show that this RFLP/nested PCR method is useful for the accurate diagnosis of CAM-resistant H. pylori infection from feces.

Clarithromycin↗
PubMed2003

Clinical efficacy of clarithromycin against uterine cervical and pharyngeal Chlamydia trachomatis and the sensitivity of polymerase chain reaction to detect C. trachomatis at various time points after treatment.

The detection and eradication of pharyngeal Chlamydia trachomatis in patients with chlamydial uterine cervicitis (commercial sex workers and others) were investigated. Pharyngeal C. trachomatis was detected in 75.0% of the commercial sex workers and in 21.9% of the other subjects. All the pharyngeal C. trachomatis-positive patients had a past history of orogenital contact. Chlamydial infection was treated with clarithromycin for 7 or 14 days. The presence of C. trachomatis was determined by polymerase chain reaction (PCR) on days 8, 15, and 22 after completion of the treatment. In the 7-day treatment group, the eradication rate of pharyngeal C. trachomatis was 53.3%, 56.7%, and 60.0% on days 8, 15, and 22, respectively, after completion of the treatment, while the eradication rate of cervical C. trachomatis was 83.3%, 96.7%, and 100% on days 8, 15, and 22, respectively. The eradication rate of pharyngeal C. trachomatis in the 7-day treatment was significantly lower than that of cervical C. trachomatis, while there was no significant difference in the 14-day treatment. The eradication rate of pharyngeal C. trachomatis in the 14-day treatment was significantly higher than that in the 7-day treatment. Since the DNA of dead organisms may be detected because of high PCR sensitivity, appropriate therapeutic judgment by PCR could be done around day 22 after completion of the treatment.

Adult↗
PubMed2005

Macrolide resistance of Streptococcus pneumoniae isolated during long-term macrolide therapy: difference between erythromycin and clarithromycin.

Longterm macrolide therapy (LTMT) has been employed as an effective therapy both for diffuse panbronchiolitis in Japan and for cystic fibrosis in European countries. However, effects on antibiotic susceptibility profiles of microorganisms, associated with such long-term administration of antibiotics, are of concern. We retrospectively identified 57 pneumococcal isolates, recovered from the same number of patients receiving either LTMT with 400 mg of clarithromycin daily (CAM group; n = 31) or 600 mg of erythromycin daily (EM group; n = 26) by reviewing the patients' records at Nara Medical University. On analysis, we found that all isolates recovered from the CAM group and 25 of the 26 recovered from the EM group were resistant to EM, showing either an MLSB: or an M phenotype. Interestingly, isolates exhibiting the M phenotype were much less frequent in the CAM group (2 of 31; 6.5%) than in the EM group (15 of 26; 57.7%). No increase in the rate of penicillin resistance was observed in either group. The macrolide resistance profiles of microorganisms may be influenced differently according to differences in the kind of macrolide antibiotics used.

Anti-Bacterial Agents↗
PubMed2006

Enhancement of antimicrobial activities of cefteram or clavulanic acid/amoxicillin against cefixime-resistant Neisseria gonorrhoeae in the presence of clarithromycin or azithromycin.

We investigated the enhancement of the antimicrobial activities of beta-lactams against cefixime (CFIX)-resistant Neisseria gonorrhoeae in the presence of macrolides. Ten strains of CFIX-resistant N. gonorrhoeae, isolated between 2000 and 2003 from male patients with urethritis at Jikei University Affiliated Hospital and its related clinics in the Tokyo metropolitan area, were tested. The fractional inhibitory concentrations of clavulanic acid/amoxicillin (CVA/AMPC), CFIX, or cefteram (CFTM), in the presence of clarithromycin (CAM) or azithromycin (AZM), against these strains were determined. Synergism, partial synergism, or additivity was recognized between CVA/AMPC or CFTM and macrolides against nine strains. Additivity and partial synergism between CFTM and macrolides against nine and ten strains, respectively, were also recognized. On the other hand, antagonism between CFIX and macrolides was recognized. These results indicate that combination antimicrobial chemotherapy, using CFTM or CVA/AMPC with macrolides, is a possible alternative treatment for CFIX-resistant N. gonorrhoeae infections.

Amoxicillin↗
PubMed1991

Simultaneous determination of clarithromycin and 14(R)-hydroxyclarithromycin in plasma and urine using high-performance liquid chromatography with electrochemical detection.

A sensitive method for the simultaneous high-performance liquid chromatographic determination of clarithromycin and its active metabolite in plasma and urine is described. Alkalinized samples were coextracted with an internal standard and analyzed on a C8 column using electrochemical detection. Recoveries were greater than or equal to 85% and consistent. Standard curves for plasma were linear in the range 0-2 micrograms/ml for both compounds (r greater than 0.99), with limits of quantification of approximately 10.03 micrograms/ml (0.5-ml sample). Within-day and day-to-day precision were good, with coefficients of variation mostly within +/- 5%; accuracy for both compounds were routinely within 90-110% of theoretical values. Standard curves for urine were linear in the range 0-100 micrograms/ml with limits of quantification of 0.5 micrograms/ml (0.2-ml sample). Urine assays also had similar within-day and day-to-day precisions and accuracy.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Comparative efficacy and safety of roxithromycin and clarithromycin in upper respiratory tract infections.

Roxithromycin 300 mg once daily was compared with clarithromycin 250 mg b.i.d. in an open randomized trial in 200 patients with upper respiratory tract infection: sinusitis, pharyngotonsillitis, and otitis media. Average treatment duration was 9 days. Roxithromycin was more effective (p less than 0.01) particularly in otitis media and pharyngotonsillitis, and better tolerated (only 4% side effects, p less than 0.05).

Aged↗
PubMed2004

Macrolides and ketolides: azithromycin, clarithromycin, telithromycin.

The advanced macrolides, azithromycin and clarithromycin, and the ketolide telithromycin are structural analogues of erythromycin. They have several distinct advantages when compared with erythromycin including enhanced spectrum of activity, more favorable pharmacokinetics and pharmacodynamics, once daily administration, and improved tolerability. This article reviews the pharmacokinetics, antimicrobial activity, clinical use, and adverse effects of these antimicrobial agents.

Anti-Bacterial Agents↗
PubMed2004

Inhibitory action of a new proton pump inhibitor, trifluoromethyl ketone derivative, against the motility of clarithromycin-susceptible and-resistant Helicobacter pylori.

We previously reported that a trifluoromethyl ketone derivative, 1-(2-benzoxazolyl)-3,3,3-trifluoro-2-propanone (TF18), exhibited the potent antibacterial activity against Helicobacter pylori, but had no urease activity. In order to clarify the mechanism of anti-H. pylori action of TF18, we evaluated the growth and motility of TF18 on clarithromycin-susceptible H. pylori (CSHP) and -resistant H. pylori (CRHP). An effective proton pump inhibitor (TF18) had remarkable dose-dependent antibacterial activity and was able to inhibit the flagellar motor of both CSHP and CRHP isolates. The antimotility effect of TF18 was more pronounced at subinhibitory concentration in CRHP than in CSHP. The swimming (the forward motion) was more sensitive to the inhibition than the tumbling. Based on the results, it is supposed that TF18 works as an uncoupler similar to the 'clutch' in a biological motor, in which counterclockwise rotation is more sensitive to the effect of TF18 than the clockwise rotation.

Anti-Bacterial Agents↗