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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cigarette smoking exerts deleterious effects not only on the respiratory tract, but also on the lung's parenchyma. The FEV is reduced in heavy chronic smokers. Persistent smoking has an unfavourable influence on mucociliary activity. According to the results of recent research almost 8 million people in the U.S. were suffering from chronic bronchitis in 1981. There is a direct correlation between the number of cigarettes smoked, over what period of time, and the incidence of chronic bronchitis. In studies with patients suffering from exacerbations of chronic bronchitis the most common bacterial pathogens found were Haemophilus influenzae, Streptococcus pneumoniae and Branhamella catarrhalis. Mycoplasma pneumoniae and certain viruses are counted amongst the non-bacterial pathogens. Antibiotics should be effective against such possible pathogens. The resistance of H. influenzae to ampicillin/amoxicillin is currently observed in at least 12% of cases, whilst H. influenzae is regularly observed to be resistant to erythromycin. Cefaclor, trimethoprim/sulphamethoxazole and amoxicillin/clavulanic acid offer satisfactory forms of treatment. Pneumonia caused by S. pneumoniae, H. influenzae, B. catarrhalis and Legionella pneumophila is often seen in smokers and patients with COLD. Haemocultures should be prepared for all hospitalized patients. Penicillin G and/or V is the agent of choice. Cefaclor or trimethoprim/sulphamethoxazole can be given to counter beta-lactamase producing H. influenzae whilst cefaclor, erythromycin, tetracycline or trimethoprim/sulphamethoxazole are used for the treatment of B. catarrhalis infections. In Legionella infections erythromycin is the preferred treatment. A combination of erythromycin and cefamandole or ceftriaxone is indicated for empirical management. Patients with COLD should be immunised with pneumococcus and influenza vaccines.
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PMID:[Smoking and lower respiratory tract infection]. 361 Mar 32

Penicillinate sulphone beta-lactamase inhibitors, sulbactam, and BL-P2013, were very effective alone and in combination with ampicillin-like penicillins against 34 strains of Legionellae. The minimum concentrations inhibiting 50% of tested isolates (MIC50) results were as follows: sulbactam, BL-P2013, and amoxicillin = 2.0 micrograms/ml; ampicillin = 1.0 microgram/ml; erythromycin = 0.5 microgram/ml; and rifampin = 0.03 microgram/ml. Synergy was commonly observed when the sulphones were combined with ampicillin or amoxicillin, generally reducing the drug minimum inhibitory concentrations (MICs) fourfold to eightfold (synergy rates 85-91%). BL-P2013 was a slightly more active inhibitor of Legionella spp. beta-lactamase than dicloxacillin or sulbactam.
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PMID:The in vitro activity of sulphones alone and in combination with ampicillin or amoxicillin against Legionella pneumophila and other Legionella spp. including beta-lactamase studies. 387 95

The morphological response of two strains of Legionella pneumophila to ampicillin 10 micrograms/ml and erythromycin 10 micrograms/ml in vitro was studied by electronmicroscopy, MIC estimations and viable counts. In the presence of ampicillin, discrete lesions appeared in the bacterial cell walls through which cytoplasmic contents extruded and lysis occurred. A few spheroplasts, together with minicells of 0.15-micron diameter, and apparently normal cells were present after exposure to ampicillin for several hours. Conversely, erythromycin initially resulted in inhibition of division and the formation of filamentous organisms. The cell walls of these filaments were eventually disrupted with numerous small membranous vesicles appearing on their surfaces. On further erythromycin treatment, breakage of the cell wall at a restricted number of sites occurred, leading to cell lysis. In the presence of erythromycin, a few morphologically normal cells were present but no spheroplasts or minicells were observed. Viable counts demonstrated that ampicillin killed the bacteria faster than erythromycin. Regrowth did not occur in the continued presence of either antibiotic, but after their removal regrowth was observed.
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PMID:Morphological response and growth characteristics of Legionella pneumophila exposed to ampicillin and erythromycin. 400 91

The possibility of indigenous Legionnaires' disease should be known as suggested by the following case : a 69-year-old man, diabetic, having never travelled out of Poitou, suffers from serious pneumonia with dyspnea needing mechanical ventilation with positive end-expiratory pressure. After failure of ampicillin, the evolution seems favourable with cotrimoxazole. However the discontinuation of this last drug is followed by a relapse which is treated with success by erythromycin. Serodiagnoses will be positive for Legionella Pneumophila serogroup I. This case, typical by its clinical features, makes itself noticed by its epidemiology and the relapse under cotrimoxazole, proving that erythromycin remains the choice antibiotic for these infections.
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PMID:[Acute respiratory distress syndrome: indigenous Legionnaires' disease (author's transl)]. 626 96

To isolate and characterize Legionella pneumophila antigens, we constructed a genomic library of L. pneumophila serogroup 1 (strain 130b). L, pneumophila DNA fragments (2.5 to 7.5 megadaltons) obtained by partial digestion with Sau 3A endonuclease and size fractionation on a sucrose density gradient were inserted into the dephosphorylated BamHI site of vector pBR322; CaCl2-treated Escherichia coli cells of strain HB101 were transformed with hybrid plasmids. To detect expression of antigens, 2,559 ampicillin-resistant transformants were transferred to nitrocellulose paper, lysed in situ, and screened by enzyme immunoassay (EIA) with E. coli-absorbed rabbit anti-L. pneumophila sera. A total of 77 (3%) of the colonies were reactive by EIA; 31 (1.2%) were strongly reactive, and 6 were strongly reactive by EIA without colony lysis. Analysis of 29 stable, strongly reactive clones by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electroblotting showed antigenic bands in 18 clones by EIA with E. coli-absorbed antisera. Absorption of antisera with heat- and Formalin-killed L. pneumophila antigen eliminated or diminished the reactivity of the antigenic bands in representative clones. These studies confirm that several L. pneumophila antigens can be cloned and expressed in E. coli.
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PMID:Cloning and expression of Legionella pneumophila antigens in Escherichia coli. 632 47

In a double blind trial erythromycin was compared with a combination of ampicillin and amoxycillin for treating adults admitted to hospital with primary pneumonia. The clinical course of 42 patients treated with ampicillin and amoxycillin was similar to that of the 49 in the erythromycin group. Fall in temperature, symptomatic recovery and radiographic improvement were similar (two-thirds made an uncomplicated recovery). Infusion-related phlebitis was more common with erythromycin. Otherwise adverse reactions were unusual. The outcome was related principally to the cause of the pneumonia with bacteraemic/antigenaemic pneumococcal pneumonia, Legionnaires' disease, other bacterial pneumonias and psittacosis having a poor prognosis. Both forms of antibiotic therapy gave similar results but we suggest that a combination of erythromycin with ampicillin may be logical initial treatment for severe pneumonia of unknown cause.
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PMID:Erythromycin compared with a combination of ampicillin and amoxycillin as initial therapy for adults with pneumonia including Legionnaires' disease. 635 70

To add information about sporadic Legionnaires' disease, 87 cases of L. pneumophila pneumonia were reviewed. Twenty cases were nosocomial infections and 67 cases were community-acquired. Most cases (64%) occurred between July and October. The mean age of patients was 51.4 years and males outnumbered females 2.5:1.0. Thirty-one percent of patients were receiving corticosteroid, immunosuppressive, or antineoplastic chemotherapy when illness began. Immunosuppression at onset of illness was more common in nosocomial infections (90%) than in community-acquired infections (14%). Seventy percent of patients had underlying diseases. Malignancies, renal failure, and transplantation were the most common conditions underlying nosocomial infections. Chronic lung disease and malignancies were the most common diseases underlying community-acquired infections. The case-fatality rate in nosocomial infection (70%) was greater than that in community-acquired disease (22%). Clinical, laboratory, and radiologic features of the cases were examined. Illness ranged from mild to severe. Extrapulmonary findings of encephalopathy and renal failure were more common in fatal than in non-fatal cases. Indirect immunofluorescent and microagglutination antibody responses plateaued by the fourth week of illness. Twenty-nine patients died. The case-fatality rate of patients receiving erythromycin (6%) was less than that of patients receiving penicillin (36%), ampicillin (28%), cephalosporin (32%), or aminoglycosides (41%). Despite erythromycin therapy, the case fatality rate for nosocomial L. pneumophilia pneumonia was unacceptably high (25%).
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PMID:Sporadic Legionnaires' disease: clinical observations on 87 nosocomial and community-acquired cases. 646 87

Disk diffusion antimicrobial susceptibility testing of members of the family Legionellaceae was accomplished on buffered charcoal yeast extract agar by allowing the bacteria to grow for 6 h before placement of the disks, followed by an additional 42-h incubation period before the inhibitory zones were measured. This system was standardized by comparing the zone sizes with the MICs for 20 antimicrobial agents of nine bacterial strains in five Legionella species and of 19 laboratory-derived, erythromycin-resistant variants of Legionella micdadei. A high, linear correlation between zone size and MIC was found for erythromycin, trimethoprim, penicillin, ampicillin, carbenicillin, cephalothin, cefamandole, cefoxitin, moxalactam, chloramphenicol, vancomycin, and clindamycin. Disk susceptibility testing could be employed to screen Legionella isolates for resistance to any of these antimicrobial agents, of which only erythromycin is known to be efficacious in the treatment of legionellosis. With selected antibiotics, disk susceptibility patterns also appeared to accurately identify to the species level the legionellae. The range of the MICs of the legionellae for rifampin and the aminoglycosides was too small to determine whether the correlation of zone size with MIC was linear. However, laboratory-derived, high-level rifampin-resistant variants of L. micdadei demonstrated no inhibition zone around the rifampin disk, indicating that disk susceptibility testing would likely identify a rifampin-resistant clinical isolate. Of the antimicrobial agents tested, the only agents for which disk susceptibility testing was definitely not possible on buffered charcoal yeast extract agar were oxacillin, the tetracyclines, and the sulfonamides.
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PMID:Disk diffusion antimicrobial susceptibility testing of members of the family Legionellaceae including erythromycin-resistant variants of Legionella micdadei. 656 6

With 28 beta-lactam antibiotics the susceptibilities of 60 strains of Legionella spp. (49 Legionella pneumophila and 11 ATCC type strains of other Legionella species) were determined. Agar dilution testing was used on buffered charcoal-yeast extract agar to which 0.1% alpha-ketoglutarate was added. The most active of the penicillins tested were ampicillin (MIC = 0.06-8 mg/l) and temocilin (MIC = 0.125 - 16 mg/l); the most active cephalosporins were ceftazidime (MIC = 0.03 - 0.5 mg/l), HR 810 (MIC = 0.06 - 1 mg/l) and cefoxitin (MIC = 0.125 - 2 mg/l). Of all the drugs tested imipenem had the most pronounced activity (MIC = .0075 - 0.06 mg/l).
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PMID:Susceptibility of Legionella spp. to imipenem and 27 other beta-lactam antibiotics. 659 34

RU 28965, a novel macrolide antibiotic, inhibited most gram-positive species at concentrations similar to that of erythromycin but was not active, even at alkaline pH, against Pseudomonas spp. or members of the family Enterobacteriaceae. Staphylococci and streptococci resistant to erythromycin were resistant to RU 28965. RU 28965 inhibited Haemophilus influenzae, including a number of beta-lactamase, ampicillin-resistant isolates, and Neisseria meningitidis and Neisseria gonorrhoeae at concentrations similar to those of erythromycin. Against anaerobic species, Bacteroides fragilis and Clostridia and Fusobacterium spp., RU 28965 was less active than erythromycin, but its activity against Campylobacter and Legionella spp. was similar to that of erythromycin.
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PMID:In vitro comparison of the activity of RU 28965, a new macrolide, with that of erythromycin against aerobic and anaerobic bacteria. 673 23


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