IgG subclasses and chronic bacterial infection. Subclass antibodies and the clinical course of chronic Pseudomonas aeruginosa lung infection in cystic fibrosis.
Explore the source record for details and available documents.
Alginates↗
SEARCH · Search PubMed
Results for “PSEUDOMONAS INFECTIONS”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Suppression of the delayed-type hypersensitivity and cell-mediated immune responses to Listeria monocytogenes induced by Pseudomonas aeruginosa.
Pseudomonas aeruginosa-mediated suppression of the immune response to Listeria monocytogenes was investigated in mice. Because delayed-type hypersensitivity (DTH) footpad swelling to L. monocytogenes was suppressed equally in lipopolysaccharide-responsive and -hyporesponsive mouse strains, the lipopolysaccharide component of P. aeruginosa could not have been the suppressive agent. Mucoid P. aeruginosa cells were no more suppressive than their nonmucoid revertants; therefore, mucoid coating was not an additional immunosuppressive element. Interleukin-1 and macrophage inhibitory factor production to L. monocytogenes and clearance of L. monocytogenes from mouse spleens were all decreased by prior Pseudomonas infection, indicating that cell-mediated immunity, as well as DTH, was decreased to a sublethal Listeria dose. The timing of Pseudomonas exposure relative to Listeria sensitization was varied. P. aeruginosa injected 24 or 6 h before or at the same time as L. monocytogenes depressed DTH to Listeria challenge 7 days later. Animals treated in this way could not respond to reinfection with L. monocytogenes at 13 days. P. aeruginosa administered to L. monocytogenes-sensitized mice at the time of footpad challenge was suppressive, but these mice responded normally upon reinfection. It appears that P. aeruginosa induced two types of suppression to L. monocytogenes: a transient suppression, affecting DTH challenge but not resensitization, and a longer lasting suppression that did not permit mice exposed to P. aeruginosa at the time of Listeria sensitization to respond to subsequent Listeria exposure.
Animals↗
DNA synthesis in Pseudomonas acidovorans infected with mutants of bacteriophage phi W-14 defective in the synthesis of alpha-putrescinylthymine.
Normal levels of the hypermodified pyrimidine, alpha-putrescinylthymine, which is formed from hydhydroxymethyluracil at the polynucleotide level (Maltman et al., J. Virol. 34:354-359, 1984), are not required in bacteriophage luminal diameterW-14 DNA for the DNA to serve as a replicative template in luminal diameterW-14-infected cells.
Bacteriophages↗
Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis.
Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF mice (Cftr(tmlUnc-/-)) and BALB/c mice, as reflected by the detection of a high number of P. aeruginosa organisms in the lung homogenates at 7 days postinfection and alginate biofilms, surrounded by polymorphonuclear leukocytes in the alveoli. In comparison, both an AHL-producing nonmucoid revertant (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore, the mouse model provides an improved method for evaluating the interaction between mucoid P. aeruginosa, the host, and antibacterial therapy.
Alginates↗
Outbreak of severe Pseudomonas aeruginosa respiratory infections due to contaminated nebulizers.
During the six months from January-June 1994, 10 cases of severe and 11 of less severe pulmonary infection caused by Pseudomonas aeruginosa were diagnosed in patients with chronic obstructive airways disease. Possible sources were evaluated. P. aeruginosa was isolated from four of the 22 nebulizers tested. The relationship of isolates from the patients and nebulizers was confirmed by sero- and phage-typing, and by arbitrarily-primed polymerase chain reaction (AP-PCR). Three types were identified and the distribution of types in patients with severe infection was as follows (one patient had a multiple infection). Type I was isolated from two nebulizers and from sputa, and/or blood and/or bronchial protected specimen brush samples or bronchial lavage fluid from four patients. Type II came from the sputa of three patients and a third nebulizer; and type III from sputa and/or blood of four further patients and another nebulizer. The data provided evidence for the relation between P. aeruginosa as a cause of infection and the contamination of the nebulizers. When nebulizer mouthpieces were changed every 24 h and sterilized between patients, no more contamination occurred, and the outbreak ceased.
Aged↗
[Pseudomonas aeruginosa colonisation in bronchiectatic patients and clinical reflections].
Bronchiectasis is characterized with irreversible dilatation according to destruction of epithelium, elastic and muscular layer. Most important cause of bronchiectasis is chronic bacterial infections. Pseudomonas aeruginosa colonisation is frequently seen in bronchiectatic patients. We aimed to find out P. aeruginosa colonisation frequency and clinical, radiological and spirometric reflections due to colonisation. We analysed 83 cases retrospectively. Mean age was 58.2 and 54.2% of them were female. Bronchiectasis were localised 19.3% in left lung, 19.3% right and 61.4% bilaterally. 29 (35.8%) normal, 28 (34.6%) obstructive, 7 (8.6%) restrictive, 17 (21%) mixed type disorders are detected in spirometric measures. Sputum culture performed in 50 cases. No microorganism colonisation determined in 30 (60%) cases, P. aeruginosa colonisation 16 (32%), Haemophilus influenzae 2 (4%), 1 (2%) Streptococcus pneumoniae and Proteus mirabilis 1 (2%) cases. P. aeruginosa colonisation determined more frequent in males (p<0.05). No significant correlation detected between colonisation and age or smoking habits (p>0.05). In cases with colonisation; clubbing and hemoptysis were significantly frequent (p<0.05). Only peribronchial thickening was significantly correlated with colonisation in radiological findings (p<0.05). In blood gase analysis PaO2, oxygen saturation were lower and PaCO2 higher in cases colonised with P. aeruginosa but it was not statisticaly significant (p>0.05). Hospitalization rate was higher in P. aeruginosa colonised cases (p>0.05). It is an important problem about mortality because of higher hemoptysis and hospitalisation requirement rate in P. aeruginosa colonised cases.
Adult↗
Serum antibody to Pseudomonas aeruginosa exotoxin measured by a passive hemagglutination assay.
A passive hemagglutination (PHA) assay for antibody to Pseudomonas aeruginosa exotoxin is described which utilizes chromic chloride-treated ovine erythrocytes coated with purified toxin. PHA antitoxin titers correlated well with those obtained by a cytotoxicity neutralization assay (r = 0.91, P less than 0.001), whereas the PHA assay was four to eight times as sensitive. The mean serum PHA titer of 16 patients convalescing from recent pseudomonas infections (log2 = 9.4 +/- 3.9) was significantly higher (P less than 0.001) than that of 17 healthy controls (2,7 +/- 2.6), and fourfold or greater rises were demonstrated in 5 of 7 patients examined sequentially. The lower levels of PHA antibody in sera from 11 of 17 controls suggested the acquisition of antitoxin secondary to asymptomatic infection.
Animals↗
Clinical and pathological observations on goats experimentally infected with Pseudomonas pseudomallei.
The effects in goats of the subcutaneous injection of varying doses of Pseudomonas pseudomallei (90 to 500,000 bacilli) suspended in normal saline are described. High doses (greater than or equal to 500 bacilli) caused acute, fatal infections. Lower doses (90 to 225 bacilli) caused acute or chronic disease when infection became established. However, 11 of 18 goats injected with the lower doses of bacilli showed no sign of infection on clinical or bacteriological examination. Response to antibiotic therapy with long acting tetracycline and chloramphenicol was minimal. Goats surviving the initial phase of infection tended to overcome the disease with a corresponding increase in the number of abscesses that were sterile at necropsy. In infected goats, clinical signs included undulating fever, wasting, anorexia, paresis of the hind legs, severe mastitis and abortion. At necropsy, abscesses were found predominantly in the spleen, lungs, subcutaneous injection site and its draining lymph node.
Animals↗
Comprehensive transcript profiling of Pto- and Prf-mediated host defense responses to infection by Pseudomonas syringae pv. tomato.
The disease resistance gene Pto encodes a serine/threonine protein kinase that confers resistance in tomato to Pseudomonas syringae pv. tomato strains that express the effector protein AvrPto. Pto-mediated resistance to bacterial speck disease also requires Prf, a protein with leucine-rich repeats and a putative nucleotide-binding site, although the role of Prf in the defense pathway is not known. We used GeneCalling, an open-architecture, mRNA-profiling technology, to identify genes that are either induced or suppressed in leaves 4 h after bacterial infection in the Pto- and Prf-mediated tomato-Pseudomonas(avrPto) interaction. Over 135 000 individual cDNA fragments representing an estimated 90% of the transcripts expressed in tomato leaves were examined and 432 differentially expressed genes were identified. The genes encode over 25 classes of proteins including 11 types of transcription factors and many signal transduction components. Differential expression of 91% of the genes required both Pto and Prf. Interestingly, differential expression of 32 genes did not require Pto but was dependent on Prf. Thus, our data support a role for Prf early in the Pto pathway and indicate that Prf can also function as an independent host recognition determinant of bacterial infection. Comprehensive expression profiling of the Pto-mediated defense response allows the development of many new hypotheses about the molecular basis of resistance to bacterial speck disease.
Bacterial Proteins↗
[Efficacy of erythromycin inhalation in chronic respiratory infection caused by Pseudomonas aeruginosa].
The prognosis of chronic respiratory tract infection with Pseudomonas aeruginosad considered to be poor. However, low-dose and long-term 14 membered macrolide, such as erythromycin or clarithromycin, treatment has been reported as effective clinically in chronic lower respiratory tract disease. There was no report to investigate the effect of macrolide on chronic biofilm related Pseudomonas aeruginosa respiratory tract infection in vivo. In a newly established murine model of chronic Pseudomonas aeruginosa respiratory infection mimicking diffuse panbronchiolitis (DPB), we investigated the effect of erythromcin inhalation on viable bacteria in the lungs. Infection was produced by placement of a plastic tube in the bronchus with inoculating. Pseudomonas aeruginosa suspended in saline was also inoculated in bronchus after intubation of the tube. Viable bacteria were constantly isolated at 10(4) 10(6) cfu-specimen from the lungs for more than 30 days. Treatment with erythromycin inhalation for four days reduced the number of viable bacteria in the lungs with statistically significant. Our result indicated that our new model of chronic respiratory tract infection is simple and provides a useful tool to study the pathogenic process and treatment of such infection. Our results also suggest that the erythromycin inhalation is effective on chronic Pseudomons aeruginosa respiratory infection.
Administration, Inhalation↗
Dissociation between results of in vitro and in vivo antibiotic susceptibility tests for some strains of Pseudomonas aeruginosa.
The relative efficacy in vivo of the polymyxin and aminoglycoside antibiotics in experimental Pseudomonas infection has apparently never been established. This study was designed to determine such efficacy in experimental infection of mice. Eleven strains of Pseudomonas aeruginosa were selected for the study, representing six of the seven recognized immunotypes. All strains were susceptible to colistin, gentamicin, and tobramycin in vitro, and all were virulent for mice. None was lethal because of preformed toxins. Infections were established in mice by intraperitoneal (i.p.) injection of 100 ID(50) of bacteria (infectious doses that would kill 50% of the mice). Graduated doses of antibiotics or saline were given subcutaneously 1 h later. Infections by three strains of P. aeruginosa were cured by low doses of all three antibiotics. Infections by two strains were relatively resistant in vivo to all three antibiotics. Infections by seven strains were relatively resistant in vivo to colistimethate. For most strains, colistimethate was less effective in vivo than gentamicin or tobramycin. To determine the influence of the size of the bacterial inoculum upon the results of chemotherapy, groups of mice were infected with serial dilutions of bacterial suspensions and treated with antibiotics. The antibiotics were more effective when a lighter bacterial inoculum was used. However, colistimethate at 30 mg/kg failed to cure some infections established with an inoculum of only 10 ID(50). To examine the possibility that death despite apparently adequate chemotherapy might be due to bacterial lysis and delayed release of toxins, numbers of viable bacteria in the peritoneal cavity of treated animals were determined by colony count. Antibiotic failure by colistimethate was associated with a steady rise in the number of i.p. bacteria. The findings support the conclusion that i.p. infections in mice with some strains of P. aeruginosa that are fully susceptible in vitro are relatively resistant to chemotherapy in vivo. The dissociation between in vitro and in vivo results was greatest for colistimethate.
Animals↗
Genito-urinary infections with Pseudomonas pseudomallei in Australian Aboriginals.
Explore the source record for details and available documents.
Adult↗
Production of spreading factor by Pseudomonas in infected bank-blood.
Explore the source record for details and available documents.
Blood Banks↗
Lymphocyte responsiveness to Pseudomonas aeruginosa in cystic fibrosis: Relationship to status of pulmonary disease in sibling pairs.
Lymphocyte proliferative responses to Pseudomonas aeruginosa and Staphylococcus aureus were evaluated in six sibling pairs with cystic fibrosis. In each pair, one sibling had advanced clinical disease, whereas the other sibling was in good clinical condition. Three in this latter group had no clinically apparent Pseudomonas bronchitis. In all cases, the average responses to Pseudomonas isolated from each sibling pair were lower in the sibling with advanced clinical disease. This difference was not observed in the responses to Staphylococcus. Normal plasma or plasma from patients with CF in good clinical condition does not restore the responses in patients with advanced clinical disease. However, plasma from patients with low or no responses to Pseudomonas inhibits the responses of responding siblings. A progressive specific lymphocyte unresponsiveness to Pseudomonas may play an important role in the increasing destructiveness of chronic pulmonary Pseudomonas infection in cystic fibrosis.
Adolescent↗
Detection of Pseudomonas aeruginosa eye infections by ultraviolet light.
Pseudomonas aeruginosa elaborates several pigment fractions that fluoresce in ultraviolet light. This fact has been used by surgeons in burn units so that treatment of subclinical P aeruginosa infections may be initiated promptly. We have determined the minimum in vitro concentration of two strains of this organism that exhibit ultraviolet light fluorescence and have applied this principle to the early detection of P aeruginosa eye infections.
Animals↗
Chronic granulomatous disease of childhood: respiratory cytology.
Chronic granulomatous disease (CGD) of childhood is a rare inherited disease in which phagocytic cells fail to produce the normal respiratory burst in response to infectious stimuli, leaving the patient particularly susceptible to infections with bacteria and fungi that produce catalase. Between 1988 and 1993 at the NIH, 58 pulmonary cytology specimens were obtained on 24 CGD patients. The number of specimens per patient ranged from one to 13 with an average 2.4. The 58 specimens included: 33 bronchoalveolar lavages; one bronchial brushing; 20 lung or pleural mass fine-needle aspirates; three pleural fluids, and one sputum. Two lung aspirates with insufficient material, five bronchoalveolar lavages performed post-treatment to confirm clinical resolution of disease, and two bronchoalveolar lavages not submitted for culture were excluded from further analysis. Of the 49 remaining specimens obtained from patients clinically suspected of having a pulmonary infection, cytology demonstrated a pathogenic organism in nine (18%). Microbiologic cultures were positive in 19/49 (39%). Cytology identified fungus in 8/13 (62%) of documented fungal infections, including four cases where microbiology was negative. Bacterial and mixed bacterial/fungal infections were usually not detected by cytology even with appropriate strains. No organisms were identified by cytology in the four cases of nocardia or the three cases of pseudomonas infection. The combination of cytology and microbiology provided the greatest diagnostic sensitivity, yielding a diagnosis in 22/49 cases (45%). Of the 27 cases with negative cytology and microbiology, an infectious agent was identified in eight upon submission of additional material: three cytology specimens and five tissue specimens. In the remaining 19 cases, no organisms were identified, however, the patients were treated presumptively. Characteristic pathologic features of granulomatous inflammation, necrosis, and giant cells were present in fine-needle aspirates, often when on organisms could be identified, but were not seen in other types of respiratory specimens.
Aspergillosis↗
Role of Cftr genotype in the response to chronic Pseudomonas aeruginosa lung infection in mice.
Patients with cystic fibrosis have a lesion in the cystic fibrosis transmembrane conductance regulator gene (CFTR), which is associated with abnormal regulation of other ion channels, abnormal glycosylation of secreted and cell surface molecules, and vulnerability to bacterial infection and inflammation in the lung usually leading to the death of these patients. The exact mechanism(s) by which mutation in CFTR leads to lung infection and inflammation is not clear. Mice bearing different mutations in the murine homolog to CFTR (Cftr) (R117H, S489X, Y122X, and DeltaF508, all backcrossed to the C57BL/6J background) were compared with respect to growth and in their ability to respond to lung infection elicited with Pseudomonas aeruginosa-laden agarose beads. Body weights of mice bearing mutations in Cftr were significantly smaller than wild-type mice at most ages. The inflammatory responses to P. aeruginosa-laden agarose beads were comparable in mice of all four Cftr mutant genotypes with respect to absolute and relative cell counts in bronchoalveolar lavage fluid, and cytokine levels (TNF-alpha, IL-1beta, IL-6, macrophage inflammatory protein-2, and keratinocyte chemoattractant) and eicosanoid levels (PGE2 and LTB4) in epithelial lining fluid: the few small differences observed occurred only between cystic fibrosis mice bearing the S489X mutation and those bearing the knockout mutation Y122X. Thus we cannot implicate either misprocessing of CFTR or failure of CFTR to reach the plasma membrane in the genesis of the excess inflammatory response of CF mice. Therefore, it appears that any functional defect in CFTR produces comparable inflammatory responses to lung infections with P. aeruginosa.
Animals↗
Successful treatment of Pseudomonas peritonitis during continuous ambulatory peritoneal dialysis.
Successful eradication of Pseudomonas peritonitis is described in 12 (57%) of 21 cases from a large continuous ambulatory peritoneal dialysis (CAPD) program at a tertiary care center. In successful cases, cure was achieved within 17 days using therapy which included aminoglycoside started routinely at the onset of symptoms and an antipseudomonal penicillin or cephalosporin derivative added as soon as pseudomonas infection was identified on culture. Of the 9 treatment failures which required catheter removal, 2 had failure of peritoneal drainage, 4 had infection with multiple and/or drug-resistant Pseudomonas strains, and 3 had persistent catheter tunnel infection which resulted in recurrent Pseudomonas peritonitis. Factors such as diabetes mellitus and pediatric age group did not prevent successful medical therapy. Predisposing factors favoring development of Pseudomonas peritonitis included technical failures and in a few cases recent antibiotic therapy. We conclude that Pseudomonas peritonitis complicating CAPD can be successfully cured without catheter removal or discontinuation of CAPD in many cases, particularly when complicating factors are not present.
Adolescent↗