Population structure and antimicrobial susceptibility of both nonpersistent and persistent Pseudomonas aeruginosa isolates recovered from cystic fibrosis patients.

Seventy-six Pseudomonas aeruginosa isolates recovered from chronically (n=18) and nonchronically (n=18) colonized cystic fibrosis (CF) patients (2002 to 2009) were grouped in separate polyclonal populations. International CF epidemic clones were not identified, but the high-risk clone ST274, also found circulating in Spanish hospitals, was present. Persistent isolates were more resistant to antibiotics than nonpersistent isolates.

In vitro prevention of Pseudomonas aeruginosa early biofilm formation with antibiotics used in cystic fibrosis patients.

The ability of antibiotics used in bronchopulmonary infections in cystic fibrosis (CF) patients to prevent Pseudomonas aeruginosa early biofilm formation was studied using a biofilm microtitre assay with 57 non-mucoid P. aeruginosa isolates (44 first colonisers and 13 recovered during the initial intermittent colonisation stage) obtained from 35 CF patients. Minimum biofilm inhibitory concentrations (BICs) of levofloxacin, ciprofloxacin, imipenem, ceftazidime, tobramycin, colistin and azithromycin were determined by placing a peg lid with a formed biofilm onto microplates containing antibiotics.

Emergence of a mutL mutation causing multilocus sequence typing-pulsed-field gel electrophoresis discrepancy among Pseudomonas aeruginosa isolates from a cystic fibrosis patient.

A multilocus sequence type (MLST) shift (from ST242 to ST996) was detected in Pseudomonas aeruginosa isolates with a uniform pulsed-field gel electrophoresis (PFGE) pattern obtained from a chronically colonized patient. MLST mutational change involved the mutL gene with the consequent emergence of a hypermutable phenotype. This observation challenges the required neutrality of mutL as an appropriate marker in MLST and alerts researchers to the limitations of MLST-only-based population studies in chronic infections under constant antibiotic selective pressure.

MALDI-TOF MS improves routine identification of non-fermenting Gram negative isolates from cystic fibrosis patients.

Identification of non-fermenting Gram-negative bacteria (NFGNB) from cystic fibrosis (CF) patients is often limited. A collection of stored NFGNB isolates (n=182) recovered from CF patients over a 15 year period was examined. The routinely reported identification during this period was compared with that obtained by MALDI-TOF MS.

[Chronic bronchial infection: the problem of Pseudomonas aeruginosa].

Pathogenic bronchopulmonary colonizations and the exacerbations produced are among the most important causes of reduced pulmonary function in patients with bronchiectasis. The most frequent pathogens in these patients are Haemophilus influenzae and Pseudomonas aeruginosa. Lesions are produced by the local inflammatory process and the vicious circle developed by antigen stimulation, the release of inflammatory mediators, the presence of neutrophils, the increase of bacterial inoculum and the release of bacterial exoproducts.

[Bacterial identification methods in the microbiology laboratory].

In order to identify the agent responsible of the infectious process and understanding the pathogenic/pathological implications, clinical course, and to implement an effective antimicrobial therapy, a mainstay in the practice of clinical microbiology is the allocation of species to a microbial isolation. In daily routine practice microbiology laboratory phenotypic techniques are applied to achieve this goal. However, they have some limitations that are seen more clearly for some kinds of microorganism.

[Polymorphism of mucA and fpvA genes in Pseudomonas aeruginosa isolates from cystic fibrosis patients: co-existence of genetically different variants].

Introduction: Pseudomonas aeruginosa is able to colonize the lungs of cystic fibrosis patients (CF) in an adaptive process that results in the selection of a dominant strain through a process of genetic variation.

Methods: One hundred and twenty tree isolates of P. aeruginosa were sequentially recovered from 6 CF patients during the routine follow-up or exacerbations over periods of 2 to 12 years in the Ramon y Cajal University Hospital (Madrid, Spain).

Unorthodox long-term aerosolized ampicillin use for methicillin-susceptible Staphylococcus aureus lung infection in a cystic fibrosis patient.

Staphylococcus aureus is a significant cause of pulmonary colonization in cystic fibrosis (CF) patients. The optimal strategy of therapy in chronically infected patients with this pathogen is not yet established. We report a successful long-term aerosolized ampicillin treatment of a 14-year-old girl with chronic symptomatic S.

Detection of high-risk human papillomavirus by two molecular techniques: hybrid capture and linear array.

A number of human papillomaviruses (HPV) are the etiological agents of cervical cancer. The present study compared the performance of the hybrid capture method with that of linear array for the detection of high-risk HPV in 218 cervical samples. For the linear array technique, the DNA was extracted using two different procedures, one manual and the other automated.