Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bronchopulmonary infections continue to be the major determinant of morbidity and mortality in patients with cystic fibrosis (CF). The basic pathogenesis of disease includes abnormal secretions and impaired mucociliary clearance. Colonization of the tracheobronchial tract with bacteria is then associated with a cycle of infection, inflammation and airway obstruction eventually leading to respiratory insufficiency. Early clinical features include persistent cough and failure to thrive. Hyperinflation and bronchial thickening are early radiographic changes suggestive of CF. Staphylococcus aureus is commonly the initial respiratory pathogen. Subsequently, Hemophilus influenzae and Pseudomonas aeruginosa colonize the respiratory tract. In addition, respiratory viruses and other pathogens such as Legionella and mycoplasma are implicated in the etiology of pulmonary infections. The culture of respiratory secretions such as sputum are important guidelines to the etiology of pulmonary infection in CF. The laboratory must be aware of the pathogens that are typical of this disease and use appropriate techniques and media. In large part, advances in treatment in CF over the past two decades are due to the availability of increasingly potent antibiotic agents. However, effective treatment must be multifaceted and include a variety of nonantimicrobial therapies. Different approaches to the antibiotic therapy of pulmonary infection in CF, including prevention, suppression, and definitive treatment are discussed. In addition to traditional antibiotic therapy, a variety of newer methods of therapy in CF are discussed. These include oral antipseudomonal antibiotics, corticosteroid therapy, aerosolized antibiotics, and continuous antimicrobial prophylaxis.
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PMID:Pulmonary infections in children with cystic fibrosis. 331 17

Infections of the respiratory tract are among the most common causes for antibiotic prescribing. Their diagnosis within the community is generally limited to clinical criteria, and microbiological information is frequently lacking. Hospitalised patients with respiratory tract infections are more likely to undergo diagnostic sampling, but difficulties remain in reliably defining a microbial aetiology, thereby providing a confident basis for antibiotic selection. In considering the role of the cephalosporins in the treatment of respiratory tract infections, over 500 published articles have been reviewed. The pharmacokinetic considerations are discussed and the limitations of existing methodology are emphasised. Individual agents are reviewed by site of sepsis and conclusions are drawn from both comparative and non-comparative studies and in relation to currently recommended regimens. Although oral cephalosporins are widely used to treat upper respiratory tract infections, none is considered ideal, especially where Haemophilus influenzae is pathogenic. In the case of lower respiratory tract infections the beta-lactamase stable parenteral cephalosporins have become widely used to treat pneumonia in hospitalised patients, especially where Gram-negative enteric bacilli are of aetiological importance. However, the lack of activity of these drugs against Legionella spp., Mycoplasma pneumoniae and Coxiella burnetii must be emphasised. Another area of increasing use is in the treatment of infective exacerbations in patients suffering from cystic fibrosis of the lungs where Pseudomonas aeruginosa is pathogenic; ceftazidime in particular has proved a useful alternative to earlier antipseudomonal penicillin antibiotics.
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PMID:Treatment of respiratory tract infections with cephalosporin antibiotics. 331 1

Two different monoclonal antibodies directed against Legionella micdadei and L. dumoffii (Genetic Systems Corp., Seattle, Wash.) were evaluated for their specificity and ability to detect L. micdadei and L. dumoffii in human and animal clinical samples and bacterial isolates in an indirect immunofluorescence assay. All three frozen sputum samples and all three Formalin-fixed sputum and liver samples from patients with culture-documented L. micdadei pneumonia were positive when tested with the L. micdadei monoclonal antibody. A Formalin-preserved lung sample from a patient with culture-documented L. dumoffii pneumonia was positive with its homologous monoclonal antibody. No cross-staining reactions were found with either monoclonal antibody on any of 25 human sputum samples tested from patients without Legionella infections. A total of 66 Legionella strains and 56 non-Legionella strains including 22 Pseudomonas strains and 34 other bacterial strains were studied. No cross-staining reactions were found except in Staphylococcus aureus Cowan 1 ATCC 12598. The lower limit of detection in seeded sputum samples was about 7 X 10(4) cells per ml for both monoclonal antibodies. Lung and tracheal lavage specimens from L. micdadei- or L. dumoffii-infected guinea pigs showed specific staining only with their respective monoclonal antibodies. The monoclonal antibodies stained homologous bacteria slightly less intensely than did the polyclonal antisera, but the signal-to-noise ratio was considerably higher for the monoclonal antibodies. No differences in sensitivity of staining of clinical specimens or bacterial isolates were noted between the monoclonal antibodies and the polyclonal reagents for L. micdadei and L. dumoffii (Centers for Disease Control, Atlanta, Ga., and BioDx, Denville, N.J. These monoclonal antibodies ae sensitive and specific, making them good candidates for laboratory diagnostic purposes.
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PMID:Legionella micdadei and Legionella dumoffii monoclonal antibodies for laboratory diagnosis of Legionella infections. 332 84

A-61827 (A-60969 is the hydrochloric salt of A-61827) is a new aryl-fluoronaphthyridine which is active against aerobic and anaerobic bacteria. The MICs of A-61827 for 90% of strains (MIC90) of staphylococci and streptococci were less than or equal to 1 microgram/ml and were generally 1 to 4 twofold dilutions less than those of ciprofloxacin for these bacteria. The MIC90S of A-61827 for members of the family Enterobacteriaceae and Pseudomonas aeruginosa were also less than or equal to 1 microgram/ml. Ciprofloxacin was 1 to 3 twofold dilutions more active than A-61827 against these gram-negative bacteria. Neisseria gonorrhoeae, Campylobacter jejuni, and Haemophilus influenzae were susceptible to less than 0.06 microgram of A-61827 per ml. The MIC90 of A-61827 for Legionella pneumophila was 0.25 microgram/ml. A-61827 was as potent or 1 to 2 twofold dilutions more potent than ciprofloxacin against these organisms. The MIC90 of A-61827 for all anaerobic bacteria was less than or equal to 4 micrograms/ml compared with less than or equal to 32 micrograms/ml for ciprofloxacin. In mouse protection tests, A-61827 was as active as ciprofloxacin against Escherichia coli, P. aeruginosa, and Salmonella typhimurium and 5 to 10 times more active than ciprofloxacin against Staphylococcus aureus and Streptococcus pyogenes. A-61827 was as active as ciprofloxacin against P. aeruginosa in a mouse pyelonephritis model and more active than ciprofloxacin and metronidazole in a mouse Bacteroides fragilis abscess model. After oral administration of 100 mg/kg to mice, the peak concentrations of A-61827 and ciprofloxacin in serum were 2.3 and 2.4 micrograms/ml and the half-lives in serum were 3.9 and 1.2 h, respectively.
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PMID:A-61827 (A-60969), a new fluoronaphthyridine with activity against both aerobic and anaerobic bacteria. 334 9

The in vitro activity of the free acid of cefetamet pivoxil (Ro 15-8075) was tested against 355 clinical isolates, namely enteropathogenic bacteria, glucose non-fermentative gram-negative rods (excluding Pseudomonas aeruginosa) and Legionella pneumophila. Ceftriaxone was included in the study as reference compound. Although the free acid of the orally active cephalosporin was generally weaker than ceftriaxone, it inhibited 88.2% and 94.5% of Enterobacteriaceae and Vibrionaceae at a concentration of 4 mg/l and 8 mg/l or less, respectively. Campylobacter jejuni proved resistant to both compounds. The activity of the new compound against glucose non-fermentative gram-negative rods was generally insufficient to be of promise for broad clinical use. Although the compound was at least twofold more active than ceftriaxone against Pseudomonas acidovorans, Pseudomonas alcaligenes and Pseudomonas cepacia, the former was at least two dilution steps less active than the latter against 14 species of the other less common glucose non-fermentative organisms.
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PMID:Cefetamet pivoxil: bacteriostatic and bactericidal activity of the free acid against 355 gram-negative rods. 340 40

The penetration of ofloxacin into bronchial secretions was evaluated in 16 patients after administration of a single oral dose of ofloxacin 400mg. Bronchial secretions were aspirated at bronchoscopy after 1 to 6 hours and serum was collected simultaneously. Ofloxacin concentrations were measured by a microbiological assay method. Considerable individual variations in serum and bronchial aspirate concentrations were recorded: bronchial aspirate concentrations varied between 1.1 mg/L and 4.5 mg/L but exceeded 1.5 mg/L in 14 of 16 patients between 1 and 6 hours. 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. It is likely that inhibitory activity will be sustained over at least 6 hours against most potential respiratory pathogens including Haemophilus influenzae, Branhamella catarrhalis, Gram-negative bacilli, Staphylococcus aureus, Legionella pneumophila and Mycoplasma pneumoniae. Streptococcus pneumoniae and Pseudomonas aeruginosa may have minimal inhibitory concentration (MIC) values lower than ofloxacin concentrations achieved in bronchial secretions, although some isolates are less sensitive. Clinical studies should establish the relevance of pharmacokinetic data to respiratory infections caused by organisms of borderline susceptibility.
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PMID:Penetration of ofloxacin into bronchial secretions. 348 25

The in vitro activity of a new penem antimicrobial agent, CGP 31608, was compared with those of imipenem, SCH 34343, and several other antimicrobial agents against approximately 600 bacterial isolates. CGP 31608 was active against gram-positive organisms, including methicillin-susceptible Staphylococcus aureus (MIC for 90% of the isolates [MIC90], 0.25 microgram/ml) and penicillin-susceptible streptococci (MIC90s, less than or equal to 2 micrograms/ml). Penicillin-resistant streptococci (including enterococci) and methicillin-resistant S. aureus were more resistant to the penem. Activities of CGP 31608 against members of the family Enterobacteriaceae were remarkably uniform, with MIC90s of 8 to 16 micrograms/ml. CGP 31608 was at least as active as imipenem and ceftazidime and more active than piperacillin against Pseudomonas aeruginosa. Drug activity was not influenced by the presence of any of 10 plasmid-mediated beta-lactamases. Against strains of Serratia marcescens, Enterobacter cloacae, and P. aeruginosa with derepressible chromosomally mediated beta-lactamases, the presence of cefoxitin did not induce increased resistance to CGP 31608. The new drug was also active against anaerobes (MIC90s, 0.25 to 8 micrograms/ml), Haemophilus influenzae (MIC90s, 0.5 to 1.0 micrograms/ml), and Legionella spp. (MIC90, 2 micrograms/ml). CGP 31608 showed an antibacterial spectrum similar to those of imipenem and SCH 34343 (except that the latter is not active against P. aeruginosa) but was generally less potent than these drugs. However, CGP 31608 demonstrated more activity (MIC90) than imipenem against P. aeruginosa, Pseudomonas cepacia, and methicillin-resistant Staphylococcus epidermidis and S. aureus.
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PMID:Comparative in vitro activity of CGP 31608, a new penem antibiotic. 349 37

The sensitivity of the indirect immunofluorescence (IFA) test in Legionella pneumophila infection is said to be maximal when a plyimmunoglobulin conjugate is used. However commercially available non-class-specific fluorescent antisera are not always sensitive enough to detect IgM antibodies as class-specific conjugates do. IFA test's drawback is its inability to detect early stages of infection. We routinely performed the microagglutination (MA) test in order to check the reliability of this test alone in screening diagnostic work for L. pneumophila group 1 infections. The 252 sera tested were from suspected or confirmed legionellosis cases. Five-hundred and thirty sera from healthy-people, 49 sera from patients with serologically confirmed chlamydia, coxiella and mycoplasma pneumonia, and ten sera from patients with Pseudomonas aeruginosa infection were used as controls. There was a good agreement between IFA and MA tests, the MA proving almost as specific as, and in some cases more sensitive than the IFA test. This was particularly evident in early stages of infection. For these reasons, together with its low cost and the ease to perform, it appears that the MA test can be a useful screening test for presumptive cases of legionellosis even on a single serum specimen.
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PMID:More experience on the microagglutination test in the diagnosis of Legionella pneumophila infection. 351 65

Bacterial plasmids have become valuable markers for the comparison of strains of nosocomial gram-negative bacilli. The importance of plasmids in nosocomial infections is primarily due to their transferable antibiotic resistance genes (R plasmids), but other plasmid-mediated traits may eventually serve as potential markers. Stable cryptic plasmids have also served to relate outbreak strains, particularly nonfermenting strains of gram-negative bacteria. Klebsiella pneumoniae and Serratia marcescens have been the major plasmid-containing species in outbreaks involving single or multiple species. Outbreaks of single species with common plasmid patterns have included the Enterobacteriaceae, Pseudomonas aeruginosa, Pseudomonas cepacia, Ewingella americana, and Legionella pneumophila. Intrageneric spread of the same or similar R plasmids has nearly always occurred within the Enterobacteriaceae in large medical centers or Veterans Administration hospitals. High-risk nurseries and burn units have been conspicuous foci for R plasmid evolution. Hospital epidemiologists and clinical microbiologists will likely have an ever-increasing need to determine the plasmid content of gram-negative bacilli producing endemic and epidemic nosocomial infections.
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PMID:Plasmids as epidemiologic markers in nosocomial gram-negative bacilli: experience at a university and review of the literature. 353 13

The susceptibility of Legionella pneumophila, Philadelphia 1 strain, to drying, pH variation, and heating was determined and compared to that of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. L. pneumophila was quite sensitive to drying, with a four log drop in viability occurring during the first 30 seconds. After 90 minutes of drying in tap water, some samples contained no viable organisms, whereas E. coli, S. aureus, and P. aeruginosa still contained several thousand viable organisms. L. pneumophila showed a two log drop in viable cells after being held for one month in tap water varying in pH from 4 to 7. This was similar to what was found for P. aeruginosa. However, at pH 8 there was a six log drop in viability for L. pneumophila which was not evident with P. aeruginosa. At pH 2 to 3, both organisms could only survive short term (minutes) exposure. Heating experiments revealed a four log drop in viability for L. pneumophila at temperatures ranging from 55 to 65 degrees C. The survival of E. coli and S. aureus was greater at these temperatures.
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PMID:The effect of drying, heat, and pH on the survival of Legionella pneumophila. 360 21


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