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Query: UMLS:C0032285 (pneumonia)
 54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Data are presented on antimicrobial resistance among isolates of Streptococcus pneumoniae, Streptoco-ccus pyogenes, Haemophilus influenzae, and Moraxella catarrhalis collected in Japan during years 1-3 (1999-2002) of the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin (PROTEKT) surveillance study. In addition to the standard panel of PROTEKT antimicrobial agents, eight other agents often used in Japan also were tested against these isolates. The majority (30%-55%) of S. pneumoniae and H. influenzae isolates were collected from patients with community-acquired pneumonia, whereas most (>70%) S. pyogenes isolates came from patients with tonsillitis/pharyngitis. Penicillin and macrolide resistance were high among isolates of S. pneumoniae, averaging 30.9%-44.5% and 77.2%-79.9%, respectively, across all centers over the 3 study years; the highest occurrences were reported among pediatric patients aged 0-2 years. The erm(B) genotype accounted for >50% of all erythromycin-resistant isolates each study year. S. pyogenes isolates were highly susceptible to most antimicrobial agents except the macrolides and tetracycline. beta-Lactamase production among H. influenzae isolates range was 8.5%-9.7% per annum. A total of 9 beta-lactamase-negative, ampicillin-resistant isolates were collected during the study. Almost all (>95%) M. catarrhalis isolates were beta-lactamase positive each year. Telithromycin was highly active against all pathogens examined in this study during all 3 years.
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PMID:Antimicrobial susceptibility of respiratory tract pathogens in Japan during PROTEKT years 1-3 (1999-2002). 1650 84

Optimal antibiotic treatment of community-acquired pneumonia (CAP) remains controversial. The clinical impact of S. pneumoniae resistance to macrolides is well documented. By contrast high dosage amoxicillin (1 g tid) remains active against such strains and no failure has been reported. The aim of this paper was to review clinical trials in community-acquired pneumonia, published from January 1, 1999, to December 31, 2005. One hundred seventy-three articles were collected, using Medline, 35 of which were analyzed, and 16 finally used. Telithromycin and pristinamycin may be used in mild to moderate CAP. Anti-pneumococcal fluoroquinolones such as levofloxacin and moxifloxacin may be used in at risk patients, but levofloxacin has only been investigated in patients with severe CAP and patients with Legionnaire's disease. Amoxicillin 1 g tid remains the drug of choice for pneumococcal CAP.
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PMID:[Acute community-acquired pneumonia. A review of clinical trials]. 1687 63

Legionella species have been widely recognized as among the important causative organisms of community-acquired pneumonia in Japan. A delay in the start of adequate treatment has a negative influence on the outcome of the disease. Telithromycin, the first oral ketolide antibacterial, was developed for the treatment of community-acquired pneumonia, including Legionella pneumonia. However, few reports have indicated the efficacy of telithromycin in community-acquired pneumonia caused by Legionella species. We report three cases of Legionella pneumonia, that were improved by early telithromycin therapy. The first patient (67-year-old man) had bronchiectasis as an underlying disease, and the second patient (73-year-old man) had diabetes mellitus and chronic renal failure. The third patient (62-year-old man) developed pneumonia after a spa tour. The diagnosis of Legionella pneumonia was made on the basis of the presence of a single IgG titer of 1/256 in case 1 and positive antigenuria in cases 2 and 3. The patients were classified into a mild group (case 1) and a moderate group (cases 2 and 3) based on the severity of the community-acquired pneumonia according to the 2005 Japanese Respiratory Society Guidelines. The results support the efficacy of telithromycin in mild to moderate Legionella pneumonia.
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PMID:[Successful telithromycin therapy of Legionella pneumonia --report of three cases]. 1692 86

Telithromycin is a ketolide, a semisynthetic derivative of the 14-membered ring macrolide antibiotics, with an expanded spectrum of activity relative to macrolides. Its good tissue pharmacokinetic characteristics allows once-daily administration, and it has been successfully employed in lower respiratory tract infections. Recent data indicate that telithromycin may exert anti-inflammatory/immunomodulatory effects that may be of use in the treatment of both acute and chronic airway diseases. This review examines the role of telithromycin in lower respiratory tract infections, analyzing published data on exacerbations of chronic bronchitis, community-acquired pneumonia and asthma in adults. In addition, pharmacokinetic and pharmacodynamic properties of the drug are considered.
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PMID:Telithromycin in lower respiratory tract infections. 1766 81

Susceptibility to a range of antimicrobial agents was determined among isolates of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae collected in 12 centers throughout Japan during years 1-5 (the respiratory seasons of 1999-2004) of the longitudinal Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin study. The most frequent source of isolates of S. pneumoniae was from patients with community-acquired pneumonia (CAP) (25.3%). Reduced susceptibility to penicillin or erythromycin resistance was common among S. pneumoniae isolates (30.9-44.5% and 77.2-81.9%, respectively). The macrolide MIC(50) for S. pneumoniae was >or=128 microg/ml (azithromycin and erythromycin) and >or=64 microg/ml (clarithromycin). The erm(B) genotype accounted for the most erythromycin-resistant isolates in each study year. H. influenzae isolates were most commonly derived from patients with CAP (26.2%). The proportion of H. influenzae isolates that were beta-lactamase positive ranged between 4.3% and 9.7%. The prevalence of beta-lactamase-negative ampicillin-resistant isolates increased from 0.4% to 2.6% between years 1 and 4 then to 19.7% in year 5. S. pyogenes isolates were highly susceptible to most antimicrobial agents except macrolides and tetracycline. Telithromycin was highly active against all three pathogens examined throughout the study.
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PMID:Antimicrobial susceptibility of respiratory tract pathogens in Japan during PROTEKT years 1-5 (1999-2004). 1850 Sep 20

The purpose of this review is to assess the benefits and risks associated with the use of the ketolide antibacterial telithromycin, currently licensed for the treatment of adults with mild to moderate community-acquired pneumonia (CAP). Telithromycin is active against both the major (Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis) and atypical/intracellular (Chlamydophila pneumoniae, Legionella pneumophila and Mycoplasma pneumoniae) CAP pathogens. It is associated with a low potential to select for resistance and has maintained its in vitro activity against isolates of respiratory pathogens in countries where it has been in clinical use for several years. In randomized clinical trials, telithromycin has demonstrated efficacy comparable to the established antibacterial classes (macrolides, fluoroquinolones and beta-lactams) in the treatment of CAP.The safety profile of telithromycin is broadly similar to that of other antibacterials used to treat CAP. The most common adverse events are gastrointestinal adverse effects and headache; these are generally mild to moderate in severity and reversible. Telithromycin appears to be well tolerated by adult patients in all age groups, including those with co-morbid conditions. In common with other antibacterials, telithromycin has the potential to affect the corrected QT interval; the concomitant use of cisapride or pimozide with telithromycin is contraindicated, while telithromycin should be avoided in patients receiving Class IA or Class III antiarrhythmic drugs. Visual disturbances (usually transient) have occurred in a small proportion of patients treated with telithromycin; it is recommended that activities such as driving are minimized during treatment. Telithromycin is contraindicated in patients with myasthenia gravis. Hepatic dysfunction may occur in some patients taking telithromycin; rare cases of acute hepatic failure and severe liver injury, including deaths, have been reported. As telithromycin is an inhibitor of the cytochrome P450 (CYP) 3A4 system, coadministration of telithromycin with drugs metabolized by this pathway may require dose adjustments (e.g. with benzodiazepines) or a temporary hiatus in the use of the coadministered drug (e.g. HMG-CoA reductase inhibitors) metabolized by CYP3A4. Telithromycin may potentiate the effects of oral anticoagulants; careful monitoring is recommended in patients receiving telithromycin and oral anticoagulants simultaneously.Although serious and sometimes fatal events have occurred in patients receiving telithromycin therapy, current data indicate that telithromycin offers an acceptable benefit risk ratio in the treatment of mild to moderate CAP.
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PMID:Benefit-risk assessment of telithromycin in the treatment of community-acquired pneumonia. 1855 90

The activity of telithromycin and comparator antibacterials was examined in isolates of Streptococcus pneumoniae and Haemophilus influenzae isolated from patients with community-acquired pneumonia (CAP), acute exacerbations of chronic bronchitis (AECB), or sinusitis during year 5 (2003-2004) of the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin global resistance surveillance study. Among S. pneumoniae, penicillin nonsusceptibility and erythromycin resistance were 35.7% and 36.0%, respectively. beta-Lactamase was produced by 12.3% of H. influenzae isolates. beta-Lactamase-negative ampicillin-resistant strains, mainly from Japan, comprised 5.2% of global H. influenzae isolates. Telithromycin and levofloxacin were the most active agents tested against S. pneumoniae and H. influenzae (>99% of isolates susceptible) isolated from patients with CAP, AECB, or bacterial sinusitis. Amoxicillin-clavulanate, levofloxacin, and telithromycin were the most active agents against multidrug-resistant S. pneumoniae.
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PMID:Antibacterial activity of telithromycin and comparators against pathogens isolated from patients with community-acquired respiratory tract infections: the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin study year 5 (2003-2004). 1913 21

Macrolides and ketolides are two families of antibiotics that share the same mechanism of action. They bind to different bases of the peptidyl transferase center of 23S RNA. The antibacterial spectrum of these drugs virtually overlaps, but dissimilarities in the affinity and number of binding sites results in differences in the intensity of their antibacterial effects (bacteriostatic or bactericidal) and their activity against strains with acquired resistance mechanisms. These agents are active against most gram-positive microorganisms and many intracellular microorganisms. Over the last ten years in Spain, the percentage of macrolide-resistant pneumococci and Streptococcus pyogenes strains has increased substantially. Telithromycin, a ketolide, has maintained the activity against these strains. Macrolides and ketolides are metabolized in the liver through CYP3A4 and they can partially block the activity of the enzyme, interfering with the metabolism of other drugs that use the same metabolic pathway. There is little elimination through the urine, with the exception of clarithromycin. High concentrations are reached in the cellular cytoplasm, but they do not diffuse to cerebrospinal fluid. These agents are included among class B drugs for use during pregnancy. Tolerance to macrolides is good and they have few associated adverse effects. The main clinical indication for these drugs is in empirical treatment of mild to moderate, community-acquired, upper and lower respiratory tract infections. Some patients treated with telithromycin developed severe hepatitis; therefore, its use is limited to community-acquired pneumonia in cases with no other available alternative.
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PMID:[Macrolides and ketolides]. 1962 12

The advanced macrolides, azithromycin and clarithromycin, and the ketolide, telithromycin, are structural analogs 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. Clarithromycin and azithromycin are used extensively for the treatment of respiratory tract infections, sexually transmitted diseases, and Helicobacter pylori-associated peptic ulcer disease. Telithromycin is approved for the treatment of community-acquired pneumonia. Severe hepatotoxicity has been reported with the use of telithromycin.
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PMID:Macrolides, ketolides, and glycylcyclines: azithromycin, clarithromycin, telithromycin, tigecycline. 2167 91

As a well-established class, macrolide antibiotics continue to enjoy a remarkable interest within pharmaceutical industry. Several stunning breakthroughs in semi-synthetic study of erythromycin A (EMA) contribute to the important role played by the macrolide class in search for new anti-infectious agents. Earlier structural modifications of EMA to address the issue of acid instability resulted in the first breakthrough in search for anti-infectious agents derived from EMA. Clarithromycin (CAM) and azithromycin (AZM) are two representative antibacterials commercialized during this period. Afterwards, continued research on the modifications of EMA to combat bacterial resistance culminated in the second breakthrough in this field. Telithromycin and cethromycin are two innovative antibacterials discovered in this period for treating community-acquired pneumonia (CAP). Recently, further structural modifications of EMA generate promising antibacterials endlessly, which will hopefully arouse another breakthrough in the near future. In this review, we will give an account of these breakthroughs and discuss the future directions of semi-synthetic research on EMA. In particular, the design and synthesis of some distinguished or promising antibacterials derived from EMA will be highlighted.
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PMID:Significant breakthroughs in search for anti-infectious agents derived from erythromycin A. 2151 74


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