|
| ||
|
|
||
Burkholderia Cepacia Complex (burkholderia + cepacia_complex)
Selected AbstractsSurvival After Lung Transplantation of Cystic Fibrosis Patients Infected with Burkholderia cepacia ComplexAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2008B. D. Alexander Within the Burkholderia cepacia complex (Bcc), B. cenocepacia portends increased mortality compared with other species. We investigated the impact of Bcc infection on mortality and re-infection following lung transplant (LT). Species designation for isolates from Bcc-infected patients was determined using 16S rDNA and recA gene analyses. Of 75 cystic fibrosis patients undergoing LT from September 1992 to August 2002, 59 had no Bcc and 16 had Bcc (including 7 B. cenocepacia) isolated in the year before LT. Of the latter, 87.5% had Bcc recovered after transplantation, and all retained their pretransplant strains. Survival was 97%, 92%, 76% and 63% for noninfected patients; 89%, 89%, 67% and 56% for patients infected with Bcc species other than B. cenocepacia; and 71%, 29%, 29% and 29% for patients with B. cenocepacia (p = 0.014) at 1 month, 1 year, 3 years and 5 years, respectively. Patients infected with B. cenocepacia before transplant were six times more likely to die within 1 year of transplant than those infected with other Bcc species (p = 0.04) and eight times than noninfected patients (p < 0.00005). Following LT, infection with Bcc species other than B. cenocepacia does not significantly impact 5-year survival whereas infection with B. cenocepacia pretransplant is associated with decreased survival. [source] Sputum antibiotic concentrations: Implications for treatment of cystic fibrosis lung infection,PEDIATRIC PULMONOLOGY, Issue 11 2007T.F. Moriarty PhD Abstract Background The success of antibiotic therapy may be predicted based on the achievement of pharmacodynamic indices (PDIs), which are determined by the susceptibility of the infecting bacteria and the concentrations of antibiotics achieved at the site of infection. The aim of this study was to determine whether PDIs associated with clinical effectiveness for ceftazidime and tobramycin were achieved at the site of infection in the lungs of cystic fibrosis (CF) patients following intravenous administration during treatment of an acute exacerbation. Methods Serum and sputum samples were collected from 14 CF patients and the concentration of both antibiotics in the samples determined. The susceptibility of bacteria cultured from sputum samples to both antibiotics alone and in combination was also determined. Results A total of 22 Pseudomonas aeruginosa isolates and 4 Burkholderia cepacia complex isolates were cultured from sputum samples with 55% and 4% of isolates susceptible to ceftazidime and tobramycin, respectively. Target PDIs for ceftazidime and tobramycin, an AUC/MIC ratio of 100 and a Cmax/MIC ratio of 10, respectively, were not achieved in serum or sputum simultaneously or even individually for any patient. Although the combination of ceftazidime and tobramycin was synergistic against 20 of the 26 isolates cultured, the concentrations of both antibiotics required for synergy were achieved simultaneously in only 38% of serum and 14% of sputum samples. Conclusion Key PDIs associated with clinical effectiveness for ceftazidime and tobramycin were not achieved at the site of infection in the lungs of CF patients. 2007;42:1008,1017. © 2007 Wiley-Liss, Inc. [source] Survival After Lung Transplantation of Cystic Fibrosis Patients Infected with Burkholderia cepacia ComplexAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2008B. D. Alexander Within the Burkholderia cepacia complex (Bcc), B. cenocepacia portends increased mortality compared with other species. We investigated the impact of Bcc infection on mortality and re-infection following lung transplant (LT). Species designation for isolates from Bcc-infected patients was determined using 16S rDNA and recA gene analyses. Of 75 cystic fibrosis patients undergoing LT from September 1992 to August 2002, 59 had no Bcc and 16 had Bcc (including 7 B. cenocepacia) isolated in the year before LT. Of the latter, 87.5% had Bcc recovered after transplantation, and all retained their pretransplant strains. Survival was 97%, 92%, 76% and 63% for noninfected patients; 89%, 89%, 67% and 56% for patients infected with Bcc species other than B. cenocepacia; and 71%, 29%, 29% and 29% for patients with B. cenocepacia (p = 0.014) at 1 month, 1 year, 3 years and 5 years, respectively. Patients infected with B. cenocepacia before transplant were six times more likely to die within 1 year of transplant than those infected with other Bcc species (p = 0.04) and eight times than noninfected patients (p < 0.00005). Following LT, infection with Bcc species other than B. cenocepacia does not significantly impact 5-year survival whereas infection with B. cenocepacia pretransplant is associated with decreased survival. [source] Cloning, expression, purification, crystallization and preliminary crystallographic studies of BceC, a UDP-glucose dehydrogenase from Burkholderia cepacia IST408ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2010Joana Rocha Bacteria of the Burkholderia cepacia complex (Bcc) have emerged as important opportunistic pathogens, establishing lung infections in immunocompromised or cystic fibrosis patients. Bcc uses polysaccharide-biofilm production in order to evade the host immune response. The biofilm precursor UDP-glucuronic acid is produced by a twofold NAD+ -dependent oxidation of UDP-glucose. In B. cepacia IST408 this enzymatic reaction is performed by the UDP-glucose dehydrogenase BceC, a 470-residue enzyme, the production and crystallization of which are described here. The crystals belonged to the orthorhombic space group P212121 and contained four molecules in the asymmetric unit. Their crystallographic analysis at 2.09,Å resolution and a molecular-replacement study are reported. [source] Differential modulation of innate immune cell functions by the Burkholderia cepacia complex: Burkholderia cenocepacia but not Burkholderia multivorans disrupts maturation and induces necrosis in human dendritic cellsCELLULAR MICROBIOLOGY, Issue 10 2008Kelly L. MacDonald Summary Burkholderia cepacia complex (BCC) bacteria cause pulmonary infections that can evolve into fatal overwhelming septicemia in chronic granulomatous disease or cystic fibrosis patients. Burkholderia cenocepacia and Burkholderia multivorans are responsible for the majority of BCC infections in cystic fibrosis patients, but B. cenocepacia is generally associated with a poorer prognosis than B. multivorans. The present study investigated whether these pathogens could modulate the normal functions of primary human monocyte-derived dendritic cells (DCs), important phagocytic cells that act as critical orchestrators of the immune response. Effects of the bacteria on maturation of DCs were determined using flow cytometry. DCs co-incubated for 24 h with B. cenocepacia, but not B. multivorans, had reduced expression of costimulatory molecules when compared with standard BCC lipopolysaccharide-matured DCs. B. cenocepacia, but not B. multivorans, also induced necrosis in DCs after 24 h, as determined by annexin V and propidium iodide staining. DC necrosis only occurred after phagocytosis of live B. cenocepacia; DCs exposed to heat-killed bacteria, bacterial supernatant or those pre-treated with cytochalasin D then exposed to live bacteria remained viable. The ability of B. cenocepacia to interfere with normal DC maturation and induce necrosis may contribute to its pathogenicity in susceptible hosts. [source] Differential invasion of respiratory epithelial cells by members of the Burkholderia cepacia complexCLINICAL MICROBIOLOGY AND INFECTION, Issue 1 2002P. M. Keig To investigate whether there are differences between members of the Burkholderia cepacia complex in their ability to invade human respiratory epithelial cells, 11 strains belonging to genomovars I,V were studied in an antibiotic protection assay using the A549 cell line. Strains belonging to genomovars II and III were more invasive than those of genomovars I, IV and V. There was also intra-genomovar variation in invasiveness. No correlation between invasiveness and other putative virulence factors of importance in B. cepacia infection in individuals with cystic fibrosis, cable pilus and B. cepacia epidemic strain marker was identified. [source] | ||||||||||