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)

Erythromycin and other macrolides have enjoyed a renaissance in the 1970s, 1980s and 1990s secondary to the discovery of "new' pathogens such as Chlamydia, Legionella, Campylobacter and Mycoplasma spp. Erythromycin is an important therapeutic agent in the paediatric age group for several reasons: (a) it exhibits proven efficacy for a wide range of infections (upper and lower respiratory tract infections, skin/skin structure infections, prophylaxis of endocarditis/acute rheumatic fever/ophthalmia neonatorum and pre-colonic surgery, campylobacteriosis, chlamydial and ureaplasmal infections, diphtheria, whooping cough, streptococcal pharyngitis) and gastrointestinal (GI) dysmotility states; (b) intravenous formulations are widely available; and (c) it is available in a number of formulations as a generic product, which is likely to result in significant cost savings. Nevertheless, erythromycin and similar earlier macrolides are characterised by a number of drawbacks including a narrow spectrum of antimicrobial activity, unfavourable pharmacokinetic properties and poor GI tolerability. Newer macrolides such as clarithromycin and azithromycin are useful in serving the needs of paediatric patients who are erythromycin-intolerant or who have infections caused by organisms that are intrinsically erythromycin-resistant, or for which a high percentage of strains are resistant (e.g. Haemophilus influenzae, Helicobacter pylori, Mycobacterium avium complex). In addition, these newer macrolides may be considered as alternatives to oral amoxicillin-clavulanic acid, second or third generation cephalosporins, or erythromycin plus sulphonamide in this patient population. Selection between specific macrolides and between macrolides and other antibiotics in the paediatric population is likely to depend, at least for the immediate future, on separate comparisons of product availability, cost, effectiveness and tolerability profiles.
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PMID:Macrolide antibiotics in paediatric infectious diseases. 870 92

Bacteria isolated from lower respiratory tract infections were collected in cooperation with institutions located throughout Japan, since 1981. IKEMOTO et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In 23 institutions around the entire Japan, 492 strains of presumably etiological bacteria were isolated mainly from the sputum of 421 patients with lower respiratory tract infections from October 1994 to September 1995. MICs of various antibacterial agents and antibiotics were determined against 70 strains of Staphylococcus aureus, 101 strains of Streptococcus pneumoniae, 92 strains of Haemophilus influenzae, 61 strains of Pseudomonas aeruginosa (non-mucoid strains), 25 strains of Pseudomonas aeruginosa (mucoid strains), 48 strains of Moraxella subgenus Branhamella catarrhalis, 14 strains of Klebsiella pneumoniae etc., and the drug susceptibilities of these strains were assessed except for those strains that died during transportation. 1. S. aureus. S. aureus strains for which MICs of oxacillin were higher than 4 micrograms/ml (methicillin-resistant S. aureus) accounted for 51.4%, but the frequency of the drug resistant bacteria decreased comparing to the previous year's 56.0%. Vancomycin showed the highest activity against S. aureus with MIC80 of 0.5 microgram/ml. 2. S. pneumoniae. Most of the drugs tested showed potent activities against S. pneumoniae. Imipenem of carbapenems showed the most potent activity with MIC80 was 0.063 microgram/ml. Erythromycin and clindamycin showed low activities with MIC80s > or = 256 micrograms/ml. Among these strains, however, 46.5% and 68.3% of strains, were quite sensitive toward these agents, respectively, with MICs of 0.063 microgram/ml. 3. H. influenzae. The activities of all drugs were potent against H. influenzae tested. Cefmenoxime a cephem, showed the most potent activity, the MICs of this drug against all of the 92 strains were 0.063 microgram/ml. Ofloxacin also showed a potent activity, and inhibited about 96% of strains with MIC of 0.063 microgram/ml. 4. P. aeruginosa (mucoid strains). Tobramycin showed the most potent activity against P. aeruginosa (mucoid strains) with MIC80 of 0.5 microgram/ml. Gentamicin, arbekacin and ciprofloxacin showed next potent activities, and their MIC80s were 2 micrograms/ml. 5. P. aeruginosa (non-mucoid strains). Tobramycin showed the most potent activity against P. aeruginosa (non-mucoid strains) with MIC80 of 2 micrograms/ml. Comparing to the activities against P. aeruginosa (mucoid strains), the activities of all the drugs tested were lower against P. aeruginosa (non-mucoid strains). 6. K. pneumoniae. Carumonam showed the most potent activity against K. pneumoniae with MIC80 of 0.063 microgram/ml. Cefozopran showed the next most potent activity with MIC80 of 0.125 microgram/ml. Ampicillin and cephems except cefpodoxime, cefozopran and cefditoren showed low activities and their MIC80s were > or = 16 micrograms/ml, and their MICs were all higher than > or = 4 micrograms/ml. 7. M. (B.) catarrhalis. Imipenem and ofloxacin showed the most potent activities against M. (B.) catarrhalis, their MIC80s were 0.063 microgram/ml. Erythromycin and minocycline showed the next highest activities with their MIC80s at 0.25 microgram/ml. Also, we investigated year to year changes in the background of patients, the respiratory infectious diseases, and the etiology of bacteria. Patients characteristics, in this period of investigation showed varieties of infectious diseases found in patients in a high age bracket, and the patients over age 60 accounted for 62.0% of all the cases. Different lower respiratory tract infectious were distributed as follows: chronic bronchitis and bacterial pneumonia accounted for the greatest number of cases with 35.6%, 27.1%, respectively, followed by
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PMID:[Susceptibilities of bacteria isolated from patients with respiratory infectious diseases to antibiotics (1994)]. 875 60

Erythromycin, clarithromycin, and azithromycin are clinically effective for the treatment of common respiratory and skin/skin-structure infections. Erythromycin and azithromycin are also effective for treatment of nongonococcal urethritis and cervicitis due to Chlamydia trachomatis. Compared with erythromycin, clarithromycin and azithromycin offer improved tolerability. Clarithromycin, however, is more similar to erythromycin in pharmacokinetic measures such as half-life, tissue distribution, and drug interactions. Misunderstandings about differences among the macrolides (erythromycin and clarithromycin) and the azalide (azithromycin) in terms of pharmacokinetics and pharmacodynamics, spectrum of activity, safety, and cost are common. The uptake and release of these compounds by white blood cells and fibroblasts account for differences in tissue half-life, volume of distribution, intracellular:extracellular ratio, and in vivo potency. Although microbiologic studies reveal that gram-positive pathogens are equally susceptible to these agents, significantly more isolates of Haemophilus influenzae are susceptible to azithromycin than to erythromycin or clarithromycin. Concentrations achieved at the infection site and duration above the minimum inhibitory concentration are as important as in vitro activity in determining in vivo activity against bacterial pathogens. Analysis of safety data indicates differences among these agents in drug interactions and use in pregnancy. Analysis of safety data reveals pharmacokinetic drug interactions for erythromycin and clarithromycin with theophylline, terfenadine, and carbamazepine that are not found with azithromycin. Both erythromycin and azithromycin are pregnancy category B drugs; clarithromycin is a category C drug. The numerous differences in pharmacokinetics, microbiology, safety, and costs among erythromycin, clarithromycin, and azithromycin can be used in the judicious selection of treatment for indicated infections.
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PMID:Erythromycin, clarithromycin, and azithromycin: are the differences real? 885 53

During 1992 and 1993, 2718 respiratory tract isolates of Haemophilus influenzae were obtained from two study centres in each of five West European countries and five study centres in the USA. beta-Lactamase production was assessed and MICs of 14 antimicrobial agents determined in a single co-ordinating laboratory using a broth microdilution method in Mueller-Hinton-lysed horse blood medium. The prevalence of strains producing beta-lactamase varied between 0 and 37.9%. In general, the highest prevalence was in study centres from Spain and the USA with slightly lower rates observed in France and the UK. Only a single confirmed beta-lactamase-negative, ampicillin resistant strain was recovered during the entire study. Erythromycin resistance, defined as an MIC of > or = 4.0 mg/L, was noted in 57.5% of isolates. Among the other antimicrobials tested, resistance rates > or = 1.0% were observed only with cefaclor (3.7%), chloramphenicol (1.4%) and co-trimoxazole (2.5%). In no case, was the prevalence of resistance or beta-lactamase production significantly greater in 1993 than in 1992.
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PMID:Antimicrobial resistance among lower respiratory tract isolates of Haemophilus influenzae: results of a 1992-93 western Europe and USA collaborative surveillance study. The Alexander Project Collaborative Group. 885 73

Application of pharmacodynamic principles for interpretation of data generated by the Alexander Project is possible for beta-lactam, quinolone and macrolide antibiotics. For beta-lactams, the time that serum concentrations remain above the MIC of the pathogen (T > MIC) is the parameter most closely linked with outcome. It has been shown that T > MIC need be only 50-60% of a dose interval. Since the MIC has the greatest influence on this parameter, a conservative estimate of activity would use the MIC90. The only beta-lactam antibiotics in the Alexander Project for which T > MIC90 for the four major pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus) exceeded 50% of the dose interval were amoxycillin/clavulanate (500/125 mg) and ceftriaxone. For macrolides, T > MIC is relevant for erythromycin and clarithromycin, but not azithromycin, for which AUC is the parameter most closely linked to outcome. Erythromycin, clarithromycin and azithromycin showed efficacy against M. catarrhalis only at MIC90. Quinolones (ciprofloxacin and ofloxacin), for which AUC is also the relevant pharmacodynamic parameter, had the greatest activity against H. influenzae and M. catarrhalis at MIC90, but were less effective against S. pneumoniae and S. aureus. Susceptibility data such as those provided by the Alexander Project can aid clinicians in choosing appropriate treatment for LRTI based on pharmacodynamic principles.
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PMID:Relevance of the Alexander Project: pharmacodynamic considerations. 885 80

Macrolide antibiotics have proven to be valuable alternatives to penicillins and cephalosporins for the treatment of a number of infections. Currently, a number of macrolides are available. When choosing a particular macrolide, the types of organisms causing the infection, the tolerability of the drug, convenience of dosing and possible drug interactions all must be taken into account. Erythromycin, azithromycin and clarithromycin are equally effective against most gram-positive organisms. However, clarithromycin and azithromycin have much better activity against Haemophilus influenza and Moraxella catarrhalis. Thus, these 2 drugs are better choices for the treatment of community-acquired pneumonia. However, the low serum concentrations of azithromycin may be a problem in patients with bacteraemia associated with with community-acquired pneumonia. Clarithromycin appears to be effective for the treatment and prophylaxis of Mycobacterium avium complex (MAC) in patients with AIDS, while azithromycin appears to be effective for prophylaxis. Treatment of MAC with azithromycin is currently undergoing study. Although clarithromycin is the macrolide of choice for the treatment of Helicobacter pylori, azithromycin is the preferred macrolide for the treatment of Chlamydia trachomatis infections. The major factor limiting the use of azithromycin and clarithromycin has been their cost. However, these drugs may be cost effective if compliance is improved due to better tolerability and more convenient dosing regimens.
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PMID:Choosing the right macrolide antibiotic. A guide to selection. 907 39

Erythromycin, the prototypical macrolide, has been widely used since the 1950s in the management of pediatric infections. Erythromycin is the drug of choice for infants and children with Legionnaire's disease, pertussis, diphtheria, lower respiratory tract infections caused by Mycoplasma pneumoniae, Chlamydia pneumoniae and Chlamydia trachomatis and enteritis caused by Campylobacter jejuni. It is also indicated for treatment of syphilis; for streptococcal, staphylococcal and pneumococcal infections; genital infections caused by Ureaplasma urealyticum; and for the prevention of rheumatic fever and endocarditis in patients who are allergic to beta-lactam antibiotics. The new macrolides azithromycin and clarithromycin are also active against Borrelia burgdorferi, Helicobacter pylori, Mycobacterium avium-intracellulare complex, Cryptosporidium spp. and Toxoplasma gondii. Erythromycin is associated with a low risk of serious side effects, although gastric distress occurs in a significant proportion of patients. Drug interactions with theophylline, carbamazepine, warfarin, cyclosporine, terfenadine and digoxin limit erythromycin use. The newer macrolides azithromycin and clarithromycin are more stable, better absorbed and better tolerated than erythromycin. Azithromycin is more active than erythromycin against Haemophilus influenzae. Excellent tissue and intracellular penetration may contribute to their clinical efficacy. In children both azithromycin and clarithromycin are indicated for acute otitis media caused by Streptococcus pneumoniae, H. influenzae and Moraxella catarrhalis and for pharyngitis/tonsillitis caused by Streptococcus pyogenes. (As of December, 1996, azithromycin for oral suspension was approved for community-acquired pneumonia in children caused by C. pneumoniae, H. influenzae, M. pneumoniae and S. pneumoniae.) Claritromycin is also indicated for acute maxillary sinusitis, uncomplicated skin and skin structure infections, pneumonia and disseminated mycobacterial infections. Azithromycin and clarithromycin are associated with a lower incidence of gastrointestinal side effects, a low rate of drug discontinuation caused by side effects and a low potential for interaction with other drugs.
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PMID:History of macrolide use in pediatrics. 910 54

A new macrolide subclass called ketolides, possess a mode of action similar to the macrolide-lincosamide-streptogramin (MLS) compounds. Utilizing reference in vitro tests, the in vitro activity of RU-66647 (a ketolide) was compared to other MLS compounds against 376 Gram-positive organisms and over 400 representative strains of Gram-negative bacilli. The ketolide's spectrum was most similar to clindamycin and an earlier drug in the series (RU-64004 or RU-004) against staphylococci and streptococci. However, RU-66647 was more active than erythromycin and azithromycin against oxacillin-resistant Staphylococcus spp. and vancomycin-resistant enterococci. Ketolide activity was more potent than other MLS drugs against vancomycin-susceptible enterococci (MIC90, 0.25-4 micrograms/ml) and all streptococci (MICs, < or = 0.25 microgram/ml). Erythromycin-resistant (constitutive) strains were generally inhibited by < or = 2 micrograms RU-66647/ml (staphylococci, 31 to 36%; streptococci, 100%; enterococci, 72%). RU-66647 was active against Haemophilus influenzae (MIC90, 2 micrograms/ml), Moraxella catarrhalis (MIC90, 0.12 microgram/ml), and pathogenic Neisseria spp. (MIC90 0.5 microgram/ml). The ketolide failed to inhibit Enterobacteriaceae, nonfermentative Gram-negative bacilli, and Bacteriodes fragilis group strains. RU-66647 was observed to be a promising new compound directed toward some organisms resistant to other MLS-class drugs.
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PMID:Antimicrobial activity of RU-66647, a new ketolide. 912 99

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In 23 institutions around the entire Japan, 567 strains of presumably etiological bacteria were isolated mainly from the sputa of 459 patients with lower respiratory tract infections during the period from October 1995 to September 1996. MICs of various antibacterial agents and antibiotics were determined against 74 strains of Staphylococcus aureus, 82 strains of Streptococcus pneumoniae, 104 strains of Haemophilus influenzae, 85 strains of Pseudomonas aeruginosa (non-mucoid strains), 18 strains of Pseudomonas aeruginosa (mucoid strains), 52 strains of Moraxella subgenus Branhamella catarrhalis, 25 strains of Klebsiella pneumoniae etc., and the drug susceptibilities of these strains were assessed except for those strains that died during transportation. 1) S. aureus. S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus) accounted for 52.7%. Arbekacin (ABK) showed the most highest activity against S. aureus with MIC80 of 0.5 micrograms/ml. Vancomycin (VCM) showed the next highest activity with MIC80 of 1 microgram/ml. These drugs showed the high activities against MRSA with MIC80S of 1 microgram/ml. 2) S. pneumoniae. Most of drugs tested showed potent activities against S. pneumoniae. Imipenem (IPM) and panipenem (PAPM), carbapenems, showed the most potent activity with MIC80S of 0.063 microgram/ml. Cefotaxime (CTX), cefmenoxime (CMX) and cefpirome (CPR) of cephems showed the next most potent activities with MIC80S of 0.25 microgram/ml. Erythromycin (EM) and clindamycin (CLDM) showed low activities with MIC80S 128 micrograms/ml or high. Among these strains, however, 48.8% and 65.9% of respective strains were quite toward sensitive these agents with MICs of 0.063 microgram/ml. 3) H. influenzae. The activities of all drugs were potent against H. influenzae test with all MICs at 4 micrograms/ml or below. Cefotiam (CTM), CMX, cefditoren (CDTR) and ofloxacin (OFLX) showed the most potent activity with MIC90S to 0.063 microgram/ml. 4) P. aeruginosa. (mucoid strains) IPM and tobramycin (TOB) showed the most potent activity against P. aeruginosa (mucoid strains) with MIC80S of 1 microgram/ml. Ceftazidime (CAZ), cefsulodin (CFS) and carumonam (CRMN) showed next potent activity, with MIC80S of 2 micrograms/ml. The MIC80S of the other drugs ranged from 4 micrograms/ml to 32 micrograms/ml. 5) P. aeruginosa (non-mucoid strains). TOB and ciprofloxacin (CPFX) showed the most potent activities against P. aeruginosa (non-mucoid strains) with MIC80S of 1 microgram/ml. The MIC80 of ampicillin (ABPC) was 128 micrograms/ml in 1994, it was 16 micrograms/ml in 1995. 6) K. pneumoniae. All drugs except ABPC were active against K. pneumoniae. CPR and CRMN showed the most potent activities against K. pneumoniae with MIC80S of 0.063 microgram/ml. The MIC80S of the other drugs ranged from 0.125 microgram/ml to 2 micrograms/ml. 7) M. (B.) catarrhalis. Against M. (B.) catarrhalis, all the drugs showed good activities with MIC80S at 4 micrograms/ml or below. And MICs of all strains were 8 micrograms/ml or below. IPM, OFLX and minocycline (MINO) showed the most potent activity with MIC80S of 0.063 microgram/ml. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. Patients' backgrounds were examine for 567 isolates from 459 cases. The examination of age distribution found that the proportion of patients with ages over 60 years was 66.3% of all the patients showing a slight increase over that in 1994. Proportion of differe
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PMID:[Susceptibilities of bacteria isolated from patients with respiratory infectious diseases to antibiotics (1995)]. 921 66

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


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