Search results for "Legionella Pneumophila"
showing 10 items of 33 documents
Phylogenetic analysis of environmental Legionella pneumophila isolates from an endemic area (Alcoy, Spain).
2015
Environmental surveillance of Legionella pneumophila is a key component of the control measures established in urban settlements to ensure water safety and quality, with the aim of minimizing and limiting opportunistic infections in humans. In this work, we present results on the detection and genetic characterization of these bacteria in the outbreak-recurrent region of Alcoy (Comunidad Valenciana, Spain) using water and biofilm samples. We were particularly interested in studying the presence and distribution of L. pneumophila in the absence of outbreak or sporadic cases of legionellosis and in comparing the efficacy of culturing from water samples with a biofilm-based detection procedure…
Comparative evaluation of three different genotyping methods for investigation of nosocomial outbreaks of Legionnaires' disease in hospitals.
2000
ABSTRACT The increased incidence of nosocomial Legionnaires' disease in two hospitals prompted investigation of possible environmental sources. In the search for an effective DNA-typing technique for use in hospital epidemiology, the performance and convenience of three methods— Sfi I macrorestriction analysis (MRA), amplified fragment length polymorphism (AFLP), and arbitrarily primed PCR (AP-PCR)—were compared. Twenty-nine outbreak-associated and eight nonassociated strains of Legionella pneumophila with 13 MRA types and subtypes were investigated. These strains comprised isolates from bronchoalveolar lavages, from environmental, patient-related sources, and type strains. All three typing…
Comparison of clinical and environmental samples of Legionella pneumophila at the nucleotide sequence level
2009
Legionella pneumophila serogroup 1 is the most common etiological agent of legionellosis. We have used clinical and environmental isolates from different sources to compare their genetic variability. We have obtained the nucleotide sequence for six protein-coding loci, included in the SBT scheme for L. pneumophila, and three intergenic regions from 127 samples, 47 of environmental origin and 80 from clinical samples. Levels of genetic variability were found to be higher in the environmental than in the clinical samples, but these did not represent a mere subset of the former. Not a single case of full identity between clinical and environmental isolates was found, which raises the possibili…
Enfermedad del legionario con afectación hepática predominante
2002
Like other pneumonias due to atypical agents, pneumonia due to Legionela Pneumophila has no characteristic clinical facts, although fever and non-productive cough are almost constant and diarrhea with changes in mental status are common. Hyponatremia and moderate transient hypertransaminasemia are common too. Severe systemic affectation after hematogenous dissemination similar to those described with typical bacterial pneumonias is a prominent difference with other atypical agents, with high mortality rates in the absence of appropriate treatment. Etiological diagnosis is very difficult and it is normally achieved late in the course of the infection. Because of diagnostic difficulties and p…
Photocatalytic inactivation of Legionella Pneumophila and aerobic bacteria consortium in water over TiO2/SiO2 fibres in a continuous reactor
2005
A continuous photoreactor, working in a total recycle mode and irradiated by a low-pressure Hg lamp, has been used to study the bactericidal effect of a photocatalyst, formed by TiO2 embedded in SiO2 fibres, on Legionella pneumophila and a consortium of common gram-negative aerobic bacteria: (Escherichia coli, Klebsiella sp., Pseudomona sp. and Proteus sp.) in water. The kinetic modeling of the inactivation process, carried out with the measured values of viable bacteria concentration at the outlet of photoreactor, evidenced that for each pass inside the photoreactor the ratio between the outlet and inlet cell concentrations was of order of 0.01 for the inactivation of L. pneumophila. For t…
A combined molecular typing approach does not discriminate Legionella pneumophila serogroup 1 strains of a predominant sequence-based type in Palermo…
2009
Summary: The sequence-based type 1,4,3,1,1,1 of Legionella pneumophila sg.1 is predominant in the Palermo city environment since several years. In this study, extended sequence-based typing and pulsed field gel electrophoresis were used in a combined approach in the aim to enhance discriminatory power of the molecular typing procedures. However, probably due to a common environmental reservoir and genetic stability, most of the strains circulating in the geographic area under study belong to the same clone and are, consequently, indistinguishable by molecular typing. Investigations of clinical cases and tracing to their environmental source require caution and support from sound epidemiolog…
Single tube real time PCR for detection of Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae and Legionella pneumophila from …
2012
We designed a multiplex real time PCR for rapid, sensitive and specific detection of Streptococcus pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae and Mycoplasma pneumoniae. The study cases consisted of 129 patients with community acquired pneumonia (CAP). Bacteriological techniques were implemented for detection of the cultivable organisms. DNA were extracted from sputa, throat swabs, bronchoalveolar lavages and tracheal aspirates and used as templates in real time PCR. The primers and probes were designed for cbpA (S. pneumoniae), p1adhesin (M. pneumoniae), mip (L. pneumophila) and ompA (C. pneumoniae). After optimization of real time PCR for every organism, the experiments w…
Cluster of Legionnaires’ Disease in an Italian Prison
2019
Background: Legionella pneumophila (Lp) is the most common etiologic agent causing Legionnaires&rsquo
One is not enough: On the effects of reference genome for the mapping and subsequent analyses of short-reads.
2020
Mapping of high-throughput sequencing (HTS) reads to a single arbitrary reference genome is a frequently used approach in microbial genomics. However, the choice of a reference may represent a source of errors that may affect subsequent analyses such as the detection of single nucleotide polymorphisms (SNPs) and phylogenetic inference. In this work, we evaluated the effect of reference choice on short-read sequence data from five clinically and epidemiologically relevant bacteria (Klebsiella pneumoniae, Legionella pneumophila, Neisseria gonorrhoeae, Pseudomonas aeruginosa and Serratia marcescens). Publicly available whole-genome assemblies encompassing the genomic diversity of these species…
Legionella pneumophila identifikācija, izmantojot MALDI-TOF MS un SBT metodes
2016
Legionella pneumophila identifikācijai un subtipēšanai tika pielietotas divas metodes – MALDI-TOF MS un SBT. Tika izmantoti 22 no ūdens izolēti ZI ”BIOR” Legionella pneumophila celmi. Ar lateksa aglutinācijas metodi tika noteiktas izmantojamās Legionella pneumophila serogrupas – 1, 2, 3 un 6. MALDI-TOF MS ekstrakcijas metode nodrošināja 100 % identifikāciju visiem Legionella pneumophila izolātiem. Pēc 17 iegūtajiem masas spektra signāliem celmi tika efektīvi subtipēti. Ar SBT metodi celmiem tika iegūti alēļu profili un sekvences tipa numuri, kopumā 15 dažādi Legionella pneumophila ST, no kuriem divi – ST2191 un ST2192 iepriekš nebija iekļauti starptautiskajā ESGLI datubāzē. Abu metožu iegūt…