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Jordi Vila

Publications and source records attributed to Jordi Vila.

At least 19 recordsLinked to original sources
PubMed2007

Association between mannose-binding lectin deficiency and septic shock following acute pyelonephritis due to Escherichia coli.

Structural and promoter MBL2 gene polymorphisms responsible for low MBL levels are associated with increased risk of infection. The objective of this study was to assess the possible association between polymorphisms of the MBL2 gene and the incidence of septic shock and bacteremia in patients with acute pyelonephritis due to Escherichia coli. The study included 62 female patients with acute pyelonephritis due to E. coli who required hospital admission, as well as 133 healthy control subjects. Six single-nucleotide polymorphisms (-550 G/C, -221 C/G, +4 C/T, codon 52 CGT/TGT, codon 54 GGC/GAC, and codon 57 GGA/GAA) in the MBL2 gene were genotyped by using a sequence-based typing technique. No significant differences were observed in the frequencies for low-expression MBL2 genotypes (O/O and LXA/O) between patients with acute pyelonephritis and healthy controls. Patients with acute pyelonephritis and septic shock had a higher incidence of low-expression MBL2 genotypes than patients with acute pyelonephritis without septic shock (odds ratio = 9.019, 95% confidence interval = 1.23 to 65.93; P = 0.03). No association was found between bacteremic acute pyelonephritis and low-expression MBL2 genotypes. We found that low-expression MBL2 genotypes predispose to septic shock but not to bacteremia in patients with E. coli-induced acute pyelonephritis. Determination of MBL2 polymorphisms could be useful for assessing the risk of septic shock in women undergoing acute pyelonephritis.

Acute Disease↗
PubMed2006

Outbreak of infection with Acinetobacter strain RUH 1139 in an intensive care unit.

OBJECTIVE: To investigate a nosocomial outbreak of infection with Acinetobacter strain RUH 1139, in the unit of high neonatal risk at University Hospital of The Andes (Merida, Venezuela). METHODS: Twenty-eight Acinetobacter strains were detected by biochemical testing and further identified to the species level by examination of the gene encoding 16S ribosomal DNA, using restriction analysis and gene sequencing. The epidemiological relationship between the strains was established by means of repetitive extragenic palindromic polymerase chain reaction (REP-PCR) and pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibilities were determined by disk diffusion. RESULTS: The spread of an epidemic strain of Acinetobacter RUH 1139 among 16 patients over a period of 3 months was demonstrated using antimicrobial susceptibility testing, PFGE, and REP-PCR. The epidemic strain was also isolated in 2 of the sampled parenteral nutrition solutions. All the patients involved in the infection outbreak had received parenteral solution. Moreover, strains of Acinetobacter RUH 1139 with another PFGE pattern and of A. baumannii were sporadically isolated before and during the outbreak. CONCLUSION: This is the first description of an outbreak of infection with this genospecies of Acinetobacter in which parenteral nutrition solution was potentially the infection source.

Acinetobacter↗
PubMed2006

Risk factors for community-onset urinary tract infections due to Escherichia coli harbouring extended-spectrum beta-lactamases.

OBJECTIVES: Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli have been increasingly recognized in the community. The aim of this study was to determine the prevalence, types of ESBLs and risk factors for community-onset ESBL-producing E. coli in urinary tract infections (UTIs). METHODS: Adults with community-onset UTIs due to ESBL-producing E. coli (cases) and non-ESBL-producing E. coli (controls) were identified through records of the clinical microbiology laboratory of the hospital. Two different periods were studied: from January 2000 to January 2001 and from October to December 2003. Controls were matched in a 3:1 ratio to case patients according to age, sex, date of isolation and residence in a long-term care facility. Potential risk factors were recorded. Isoelectric focusing as well as PCR and DNA sequencing were used to characterize the bla(TEM), bla(SHV) and bla(CTX-M) genes. A possible clonal relationship among the strains was determined by repetitive extragenic palindromic sequence PCR. RESULTS: The prevalence of infection due to ESBL-producing E. coli increased from 0.47% in 2000 to 1.7% in 2003 (P < 0.001). Community-onset ESBL-producing E. coli infection shifted from 50% in the first period to 79.5% in 2003 (P < 0.001). Nineteen cases and 55 matched controls of community-onset ESBL-producing E. coli UTI were included. ESBL-producing E. coli strains were clonally unrelated. On univariate analysis, genitourinary pathology (P < 0.03), previous bacterial infection (P = 0.01), intravenous antibiotic treatment (P = 0.01), hospitalization in the previous 12 months (P = 0.04) and previous exposure to oral second-generation cephalosporins (P < 0.05) were associated with community-onset infection due to ESBL-producing E. coli. In our regression model, only previous exposure to second-generation cephalosporins was strongly associated with E. coli harbouring ESBLs (OR, 21.42; CI 95%, 5.38-85.22; P < 0.05). In the first period, only TEM- and SHV-derived ESBLs were identified. The enzymes were characterized as members of the TEM group (60%), SHV group (16%) and CTX-M group (24%). CONCLUSIONS: We detected a marked increase in infections due to ESBL-producing E. coli, especially in the community, in the periods studied. Only previous exposure to the oxyimino cephalosporin cefuroxime, and not to ciprofloxacin, aminoglycosides or third-generation cephalosporins, was predictive of an ESBL-producing E. coli community-onset infection in our area. The emergence of the CTX-M type of beta-lactamase in E. coli follows closely the spread of ESBLs in community isolates.

Community-Acquired Infections↗
PubMed2006

Proteomic analysis of a fraction enriched in cell envelope proteins of Acinetobacter baumannii.

Acinetobacter baumannii is a multiresistant opportunistic nosocomial pathogen. A protein fraction was purified and analyzed by 2-DE. Twenty-nine major protein spots were selected for protein identification using trypsin digestion and MS analysis. As the A. baumannii genome has not yet been described, protein identification was performed by homology with other Acinetobacter species in the NCBi database. We identified ribosomal proteins, chaperones, elongation factors and outer membrane proteins (Omp), such as OmpA and the 33-36-kDa OMP. Proteomic analysis of A. baumannii provides a platform for further studies in antimicrobial resistance.

Acinetobacter baumannii↗
PubMed2006

Group A streptococcal infections in injection drug users in Barcelona, Spain: epidemiologic, clinical, and microbiologic analysis of 3 clusters of cases from 2000 to 2003.

An unexplained resurgence of Group A streptococci (GAS) infections has been observed since the mid-1980s in the United States and Europe, particularly among intravenous drug users (IDUs). Several risk factors have been identified. Mutations in the capsule synthesis regulator genes (csrRS) have been associated with an increase in virulence. From January 1998 to December 2003, we conducted a prospective and retrospective descriptive analysis of invasive GAS soft-tissue infections in IDUs in Barcelona, Spain. Clinical features were collected, and we conducted a surveillance study to identify risk factors associated with GAS soft-tissue infections. We analyzed chromosomal DNA by low cleavage restriction enzymes and used pulsed-field gel electrophoresis (PFGE) and variable gene sequence typing (VGST) of the emm gene to disclose the epidemiologic relationship between the strains. We analyzed the influence of clonality (M-type) and mutations in csrRS genes of these strains on clinical features. We identified 44 cases, all of which were grouped in 3 clusters: fall 2000, fall 2002, and fall 2003. Cellulitis with or without abscesses (75%) and fever (90.9%) were the most common clinical manifestations. Distant septic complications were infrequent (18.2%). Although all patients had severe infections (mainly bacteremic needle abscesses), their outcome with antibiotic therapy, usually beta-lactam, was successful in all cases. However, surgery was needed in 40.9% of patients. Through the surveillance study we found that infected patients had a higher number of drug injections per day (odds ratio [OR], 18.84; 95% confidence interval [CI], 4.83-79.4; p<0.00001), shared paraphernalia for drug use more frequently (OR, 11.11; 95% CI, 3.24-39.04; p<0.0001), were in a higher proportion both currently unemployed and homeless (OR, 4.22; 95% CI, 1.5-12.15; p<0.0001), were not in a methadone maintenance program (OR, 0.03; 95% CI, 0-0.19; p<0.00001), and more often bought drugs at a specific site (OR, 33.92; 95% CI, 7.44-174.93; p<0.00001) and from a specific dealer (OR, 72; 95% CI, 8-3090; p<0.00001), compared with patients not infected. The fall 2000 cluster was polyclonal, whereas the other 2 clusters were mainly due to the same strain of GAS (emm 25.2), and were defined as epidemic outbreaks. Clinically, the cases due to the clonal strain presented abscesses and needed surgery more frequently (p<0.001 and p=0.005, respectively). On the other hand, mutations in the csrRS genes were not associated with invasive GAS soft-tissue infection. There has been an increase in the number of cases of invasive GAS soft-tissue infections in IDUs in Barcelona, which seems to be related to drug users' habits and their socioeconomic status. Clonality (emm 25.2) but not mutations in the csrRS genes was associated with more severe GAS soft-tissue infections.

Adolescent↗
PubMed2006

Detection of virulence determinants in clinical strains of Salmonella enterica serovar Enteritidis and mapping on macrorestriction profiles.

A total of 80 strains of Salmonella enterica serovar Enteritidis, causing gastroenteritis (G) or bacteraemia (B), and three control strains (C), were subjected to: (i) detection of 14 chromosomally and 1 plasmid-located virulence genes by PCR, (ii) detection of DNA polymorphisms by XbaI and BlnI PFGE, and cluster analysis, (iii) mapping of the 15 screened sequences on macrorestriction profiles and (iv) comparison of the screening and mapping results with data available for other Salmonella strains. Identical virulence genotypes and very similar macrorestriction profiles were shown by most S. Enteritidis strains. However, a number of B strains belonged to genomic types with polymorphisms affecting fragments carrying (SPI2-slyA), (SPI2-slyA-phoP/Q-agfA), (SPI4 and/or stn) and spvC. The information obtained provides the basis for further studies on the genetic background of virulence and the molecular epidemiology of S. Enteritidis.

Chromosome Mapping↗
PubMed2006

Relationship of phylogenetic background, biofilm production, and time to detection of growth in blood culture vials with clinical variables and prognosis associated with Escherichia coli bacteremia.

In patients with Escherichia coli bacteremia, data on the relationship of phylogenetic background, biofilm production, and degree of bacteremia with clinical variables and prognosis are scarce. During a 1-year period, all adults with bacteremia due to Escherichia coli diagnosed at a university center were enrolled. Determination of phylogenetic background, biofilm production, and genotyping was performed with all strains, and the time to positivity of blood culture vials was recorded. A total of 185 episodes of diverse-source E. coli bacteremia was analyzed. Strains of phylogroup D were predominant (52%). Phylogroup A isolates were associated with pneumonia and prior antibiotic intake, B1 with an abdominal source of infection, B2 with the absence of urological abnormalities, and D with urological abnormalities and age below 65 years. Resistance to antibiotics and no biofilm production were concentrated in phylogroup A strains. Biofilm production was not associated with any clinical variable. An immunocompromising condition (odds ratio [OR] = 5.01, 95% confidence interval [CI] = 1.4 to 17.9), peritonitis (OR = 17, 95% CI = 3.32 to 87), pneumonia (OR = 9.97, 95% CI = 1.96 to 50.6), and </=7 h to bacteremia detection (OR = 4.37, 95% CI = 1.38 to 13.8) were the best predictors of a fatal outcome. Results from this study suggest that the distribution of phylogenetic backgrounds among E. coli strains involved in diverse-source bacteremia may be subject to geographical variation and that, in afflicted individuals, some high-risk sources, the patient's underlying condition, and the degree of bacteremia are more important than microbial factors in determining the outcome. Time to positivity of blood culture vials may be a variable of potential clinical impact.

Aged↗
PubMed2006

Nosocomial bacteremia due to an as yet unclassified acinetobacter genomic species 17-like strain.

We describe a case of bacteremia due to an as yet unclassified Acinetobacter genomic species 17-like strain. The recognition of this microorganism as non-Acinetobacter baumannii may have important epidemiological implications, as it relieves the hospital of the implementation of barrier precautions for patients infected or colonized as may be necessary with a multiresistant A. baumannii epidemic.

Acinetobacter↗
PubMed2006

Dissemination of Salmonella enterica serotype agona and multidrug-resistant Salmonella enterica serotype typhimurium in Cuba.

The molecular epidemiology, antimicrobial susceptibility, and mechanisms of resistance of 34 Salmonella spp. strains causing acute gastroenteritis, isolated from different provinces in Cuba, were determined. Sixty-four percent of the strains showed multiresistance. Salmonella typhimurium was the most frequent with 15 strains (44%), 13 of which belonged to phagotype 104 and presented similar genetic profiles of pulsed field gel electrophoresis. High levels of resistance to tetracycline (53%), spectinomycin (50%), ampicillin (44%), and chloramphenicol (41%) were found. Resistance to tetracycline was associated with the tet G and tet A genes. Resistance to ampicillin was caused by the presence of beta-lactamases, mainly the CARB type. The floR gene was the main mechanism of resistance to chloramphenicol. Our results showed an antimicrobial susceptible clone of Salmonella enterica serotype Agona in two separate regions. This is the first report of the widespread dissemination of a multiresistant clone of S. enterica serotype Typhimurium definitive phage type 104 in Cuba.

Anti-Bacterial Agents↗
PubMed2005

A role for human Sp alpha as a pattern recognition receptor.

Human Sp alpha is a soluble protein belonging to group B of the scavenger receptor cysteine-rich (SRCR) superfamily for which little functional information is available. It is expressed by macrophages present in lymphoid tissues (spleen, lymph node, thymus, and bone marrow), and it binds to myelomonocytic and lymphoid cells, which suggests that it may play an important role in the regulation of the innate and adaptive immune systems. In the present study we show that recombinant human Sp alpha (rSp alpha) binds to the surface of several gram-positive and gram-negative bacterial strains. Competition studies indicated that such binding is mediated by the recognition of lipoteichoic acid (LTA) and lipopolysaccharide (LPS), respectively, through nonoverlapping sites on the Sp alpha molecule. The most conserved part of LPS (2-keto-3-deoxyoctulosonic acid and lipid A) was shown to be involved in the recognition by Sp alpha. Bacterial binding studies using the SRCR domain 1 of Sp alpha showed that this domain retains both the LPS and LTA binding activities, indicating that both bacterial interacting sites are retained in a single SRCR domain. Furthermore, rSp alpha induced aggregation of gram-positive and gram-negative bacteria strains. On the other hand, rSp alpha inhibited tumor necrosis factor-alpha secretion by human monocytes stimulated with LPS or LTA. Binding of Sp alpha to conserved components of bacterial surfaces and modulation of the monocyte response indicate that this molecule is an active constituent of the innate immune response of the host.

Amino Acid Sequence↗
PubMed2005

A double mutation in the gyrA gene is necessary to produce high levels of resistance to moxifloxacin in Campylobacter spp. clinical isolates.

The aim of this study was to compare different fluoroquinolones against Campylobacter spp., analysing the molecular mechanisms of resistance. Moxifloxacin exhibited the greatest activity of the quinolones tested, being active against isolates carrying a single mutation in the gyrA gene. High resistance levels to moxifloxacin were related to the presence of a double gyrA mutation.

Amino Acid Substitution↗
PubMed2005

Ciprofloxacin, salicylate, and 2,4-dinitrophenol decrease production of AmpC-type beta-lactamase in two Citrobacter freundii clinical isolates.

The effect of ciprofloxacin and two mar RAB inducers on the susceptibility to beta-lactam antibiotics in two AmpC beta-lactamase semi-constitutive producer Citrobacter freundii clinical isolates (the DM 1 and DM 2 strains) was studied. Possible changes in outer membrane protein expression, permeability to cephaloridine, active efflux, and hydrolytic activity of beta-lactamase-crude extracts were evaluated under the influence of ciprofloxacin, sodium salicylate, and 2,4-dinitrophenol. Results were compared with those of the effect of the same three chemicals on a normally beta-lactamase-inducible wild-type C. freundii strain. The three assayed compounds decreased beta-lactamase hydrolysis on cephaloridine in both the two clinical isolates as well as in the wild-type strain. However, only the DM 1 and DM 2 strains showed increased susceptibility to beta-lactams. Sodium salicylate and 2,4-dinitrophenol, but not ciprofloxacin, reduced the expression of a 45-kDa outer membrane protein in the three studied strains, which was accompanied by a 4- to 20-fold diminution in permeability to cephaloridine. In conclusion, two mar RAB inducers and ciprofloxacin induced the Mar phenotype and repressed AmpC beta-lactamase synthesis in the DM 1 and DM 2 clinical isolates.

2,4-Dinitrophenol↗
PubMed2005

Evidence for a reserpine-affected mechanism of resistance to tetracycline in Neisseria gonorrhoeae.

The presence of a reserpine-affected mechanism of tetracycline resistance was investigated in 17 Neisseria gonorrhoeae clinical isolates. To establish this fact the MIC of tetracycline in the presence and absence of reserpine was determined, and, in addition, mechanisms of tetracycline resistance were analyzed by PCR. The results showed that reserpine affects the MIC of tetracycline at least 4-fold in all isolates, including those containing the tetM gene. An inhibitory effect of reserpine against the MtrCDE efflux system was ruled out by using strains either with an inactive or with an unrepressed MtrCDE system. The results suggest the presence of a constitutive system of resistance to tetracycline, by a possible efflux pump, which may be inhibited by reserpine. Further studies are required to determine the exact nature of the action of reserpine on the MIC of tetracycline.

Anti-Bacterial Agents↗
PubMed2005

Relationship between mutations in the gyrA gene and quinolone resistance in clinical isolates of Corynebacterium striatum and Corynebacterium amycolatum.

Quinolone susceptibility was analyzed in 17 clinical isolates of Corynebacterium striatum and 9 strains of Corynebacterium amycolatum by the E-test method in Mueller-Hinton agar plates. The C. striatum ATCC 6940 strain was used as a control strain. The amplified quinolone resistance determining regions of the gyrA genes of C. amycolatum and C. striatum were characterized. Four in vitro quinolone-resistant mutants of C. amycolatum were selected and analyzed. Both in vivo and in vitro quinolone-resistant strains of C. amycolatum showed high levels of fluoroquinolone resistance in strains with a double mutation leading to an amino acid change in positions 87 and 91 or positions 87 and 88 (unusual mutation) of GyrA, whereas the same concomitant mutations at amino acid positions 87 and 91 in GyrA of C. striatum produced high levels of resistance to ciprofloxacin and levofloxacin but only showed a moderate increase in the MIC of moxifloxacin, suggesting that other mechanism(s) of quinolone resistance could be involved in moxifloxacin resistance in C. amycolatum. Moreover, a PCR-RFLP-NcoI of the gyrA gene was developed to distinguish between C. amycolatum and C. striatum species.

Amino Acid Sequence↗
PubMed2005

Expression of interleukin-8 receptors (CXCR1 and CXCR2) in premenopausal women with recurrent urinary tract infections.

The migration of neutrophils through infected tissues is mediated by the CXC chemokines and its receptors (CXCR1 and CXCR2). It has been proposed that a CXCR1 deficiency could confer susceptibility to acute pyelonephritis in children. The objective of the study is to assess the surface expression of CXCR1 and CXCR2 and the existence of polymorphisms in the CXCR1 gene in premenopausal women with recurrent urinary tract infections. The study included 20 premenopausal women with recurrent urinary infections, with normal urinary tracts, and without diseases potentially associated with relapsing urinary infections and 30 controls without previous urinary infections. The levels of CXCR1 and CXCR2 expression on neutrophils were measured and analyzed by flow cytometry by measuring the mean fluorescence intensity (MFI) channel. The promoter and coding regions of the CXCR1 gene were analyzed for the presence of polymorphisms by a sequence-based typing method. Patients with recurrent urinary tract infections exhibited median levels of CXCR1 expression, determined from MFI values, similar to those of the controls. The analysis of CXCR2 showed that patients with recurrent urinary infections had lower median levels of expression, determined from the MFI values, than the controls (P = 0.002, Mann-Whitney U test). No polymorphisms were detected at the promoter or at the exon 1 region of the CXCR1 gene either in the patients or in the controls. Polymorphisms were detected at the exon 2 of CXCR1, but their frequencies did not differ between patients and controls. We have found a low level of CXCR2 expression in patients with recurrent urinary tract infections. These results suggest that a low level of CXCR2 expression may increase the susceptibilities of premenopausal women to urinary tract infections.

Adult↗
PubMed2005

Prevalence of pathogenicity island IICFT073 genes among extraintestinal clinical isolates of Escherichia coli.

Uropathogenic Escherichia coli is the most common cause of urinary tract infection (UTI). Cystitis in women is by far the most common UTI; pyelonephritis in both sexes and prostatitis in men are more severe but are less frequent complaints. The ability of E. coli to cause UTI is associated with specific virulence determinants, some of which are encoded on pathogenicity islands (PAI). One such PAI (PAI IICFT073), of the prototypical uropathogenic E. coli strain CFT073, contains 116 open reading frames, including iron-regulated genes, carbohydrate biosynthetic genes, the serine protease autotransporter picU, a two-partner secretion system, a type I secretion system, mobility genes, and a large number of hypothetical genes. To determine the association of PAI IICFT073 with UTI, PCR was used to examine the prevalence of the five virulence-associated loci among the ECOR collection and a collection of E. coli isolated from patients with cystitis, pyelonephritis, prostatitis, or septicemia. All PAI IICFT073 loci were found to be more prevalent among the B2 phylogenetic group than any other group within the ECOR collection and among invasive prostatitis strains than were cystitis or pyelonephritis strains. These data support the theory that clinical isolates causing prostatitis are more virulent than those producing cystitis or pyelonephritis in women.

Bacterial Proteins↗
PubMed2005

Quinolone-resistant uropathogenic Escherichia coli strains from phylogenetic group B2 have fewer virulence factors than their susceptible counterparts.

The prevalence of 31 virulence factors was analyzed among nalidixic acid-susceptible and -resistant Escherichia coli strains from phylogenetic group B2. Hemolysin, cytotoxic necrotizing factor 1, and S and F1C fimbriae genes were less prevalent among nalidixic acid-resistant E. coli strains. Quinolone resistance may be associated with a decrease in the presence of some virulence factors.

Anti-Infective Agents↗