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Guillem Prats

Publications and source records attributed to Guillem Prats.

At least 19 recordsLinked to original sources
PubMed2006

ESBL- and plasmidic class C beta-lactamase-producing E. coli strains isolated from poultry, pig and rabbit farms.

This study aims to determine the presence of extended-spectrum (ESBL) and plasmidic class C beta-lactamase-producing Enterobacteriaceae in poultry, pig and rabbit farms of Catalonia (Spain). PFGE typing showed a low clonal relationship among strains carrying these mechanisms of resistance. Ninety-three percent of them were resistant to two or more of the non-beta-lactam antimicrobials tested and harboured ESBL and plasmidic class C beta-lactamases. Greater diversity of these enzymes was found in strains from poultry farms, the CTX-M-9 family, especially CTX-M-14, with CMY-2 being the most frequent. The isolation of TEM-52 and SHV-2-producing Escherichia coli strains from these animal farms is noteworthy. In contrast, 73% of the strains from pig farms had CTX-M-1, and neither the CMY-type nor CTX-M-9 family enzyme was found. Likewise, it is the first time that CTX-M-1 and SHV-5 encoding strains have been isolated in pigs. On the other hand, in rabbit farms CTX-M-9 family was also the most frequent, being detected in three of a total of four strains. The last one showed a CMY-2, for the first time detected in these animals, too. In conclusion, commensal E. coli strains of food-producing animal farms are a reservoir of ESBL and plasmidic class C beta-lactamases.

Animals↗
PubMed2006

Extended-spectrum beta-lactamase-producing Enterobacteriaceae in different environments (humans, food, animal farms and sewage).

OBJECTIVES: This study aimed to determine the presence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in different environments. METHODS: Clinical samples and stool samples from animal farms, sewage, human faecal carriers attending the emergency room and faecal carriers in the context of food-borne disease outbreaks were subcultured onto MacConkey agar supplemented with cefotaxime for the detection of ESBL-producing Enterobacteriaceae. Identification, susceptibility pattern and ERIC-PCR were used for clone delineation in each sample. Community consumption of antibiotics was also recorded. RESULTS: An ESBL-producing Enterobacteriaceae prevalence of 1.9% was observed in human infections. A cross-sectional survey of human faecal carriers in the community showed a general prevalence of 6.6% with a temporal distribution. High use of antibiotics in winter coincided with a lower prevalence in carriers. ESBL-producing Enterobacteriaceae were detected in the five samples of human sewage, in samples from 8 of 10 pig farms, 2 of 10 rabbit farms, from all 10 poultry farms and in 3 of 738 food samples studied. Faecal carriage of ESBL-producing Enterobacteriaceae was detected in samples from 19 of 61 food-borne outbreaks evaluated. All food-borne outbreaks were due to enteropathogens. The prevalence of carriers in these outbreaks ranged from 4.4% to 66.6%. CONCLUSIONS: This widespread occurrence of ESBL-producing Enterobacteriaceae suggests that the community could act as a reservoir and that food could contribute to the spread of these strains.

Agriculture↗
PubMed2006

Quinolone, fluoroquinolone and trimethoprim/sulfamethoxazole resistance in relation to virulence determinants and phylogenetic background among uropathogenic Escherichia coli.

INTRODUCTION: The goal of this study was to assess how resistance to quinolones, fluoroquinolones and trimethoprim/sulfamethoxazole relates to the virulence potential and phylogenetic background of clinical Escherichia coli isolates. METHODS: Among 150 uropathogens (21% resistant to quinolones, 12% resistant to fluoroquinolones and 29.3% resistant to trimethoprim/sulfamethoxazole), E. coli phylogenetic group, 15 virulence-associated genes and 7 O antigens were analysed. Clonal group A (CGA) and genomic PCR profiles were studied among trimethoprim/sulfamethoxazole-resistant isolates. RESULTS: Isolates susceptible to the three antimicrobial agents were significantly associated with phylogenetic group B2, whereas resistant isolates exhibited shifts to non-B2 groups (quinolone and fluoroquinolone-resistant isolates to group A; trimethoprim/sulfamethoxazole-resistant isolates to group D). Diverse virulence traits, including UTI-associated O antigens, were significantly less frequent among resistant isolates, particularly those resistant to fluoroquinolones (median score, 3.9 virulence factors/strain) and also to quinolones (5.2) or trimethoprim/sulfamethoxazole (6.4), as compared with the corresponding drug-susceptible isolates (median scores of 7.9, 8.6 and 7.9, respectively). Among 44 trimethoprim/sulfamethoxazole-resistant isolates, 3 (6.8%) belonged to CGA. All these 3 CGA strains caused pyelonephritis (P=0.02) and exhibited the consensus virulence profile of previously described CGA strains from abroad. CONCLUSIONS: E. coli isolates resistant to quinolones, trimethoprim/sulfamethoxazole and especially fluoroquinolones were associated with reductions in virulence traits and shifts to non-B2 phylogenetic groups. Moreover, fluoroquinolone resistance usually occurred in low-virulence E. coli group A isolates rather than in isolates from groups B2 and D which had lost virulence traits. CGA accounted for 23% of trimethoprim/sulfamethoxazole-resistant E. coli producing pyelonephritis.

Adult↗
PubMed2006

[Tuberculous meningitis: a comparative study in relation to concurrent human immunodeficiency virus infection].

INTRODUCTION: This study assesses the epidemiological and clinical data, as well as therapy and evolution in a recent series of patients with tuberculous meningitis (MT). A comparative study was conducted between adult MT patients with and without concurrent human immunodeficiency virus (HIV) infection. METHODS: From 1987 to 2000, 75 episodes of MT were diagnosed, 39 of them (52%) in patients with prior HIV infection. A comparative study was performed of variables related to the presence or absence of HIV and MT coinfection. RESULTS: MT was more frequent in HIV patients (6.4% versus 1.2%, p < 0.01). CD41 lymphocyte value in HIV patients was 52 +/- 66 cells/mm3. There were no significant differences in clinical manifestations or cerebrospinal fluid biochemical alterations between the two groups. Extrameningeal TB was more frequent in patients with HIV coinfection than those without (61.5% vs. 36.1%, p = 0.03). Radiological alterations on cranial studies were more frequent in HIV-infected patients. Treatment with four antituberculosis drugs was also more frequent in HIV-infected patients (61.5% vs. 13.9%, p = 0.01). There were no differences in adverse effects between the groups. Overall mortality (20.5% vs. 22.51%) and neurological sequelae (7.7% vs. 5.6%) were also similar. CONCLUSIONS: Half of our MT patients were coinfected with HIV. Their clinical, microbiological and evolutionary characteristics were comparable to those of patients without HIV infection. These results indicate that the diagnostic and therapeutic strategies applied in MT patients with or without HIV coinfection can be similar.

Adolescent↗
PubMed2006

[Characterization of Escherichia coli isolates derived from phylogenetic groups A and B1 causing extraintestinal infection].

INTRODUCTION: Escherichia coli isolates from the non-pathogenic phylogenetic groups A and B1 rarely cause extraintestinal infections. The aim of this study was to analyze 37 E. coli isolates pertaining to phylogenetic groups A and B1 and compare them with 37 E. coli isolates from group B2 and 31 from group D, which caused the same infections. METHODS: Among 105 E. coli isolated from the urine of patients with cystitis and pyelonephritis and from the blood of patients with urinary-source and other-source bacteriemia, the E. coli phylogenetic groups, 15 virulence-associated genes, 7 O-antigens and fluoroquinolone resistance were analyzed. RESULTS: E. coli from groups A and B1 showed fewer virulence determinants (median 3.5) than E. coli from group B2 (8.6, P < 0.01) or D (5.3, P < .001); however, a subgroup containing 3 isolates from group A and 5 from B1 harbored 5 or more factors. E. coli from groups A/B1 were associated with resistance to fluoroquinolones (74%, P < .001), whereas E. coli from group B2 were associated with susceptibility to this antibiotic (76%, P = .003). E. coli from groups A/B1 were isolated significantly more frequently in patients with pyelonephritis or sepsis and local or general factors favoring infection, association not observed in patients with cystitis. CONCLUSIONS: Even though most of the E. coli isolates from phylogenetic groups A and B1 presented a low virulence potential, they were able to cause extraintestinal infections, particularly in compromised patients.

Adolescent↗
PubMed2006

Prulifloxacin: a new antibacterial fluoroquinolone.

In the last few years, the antimicrobial activity, efficacy and relative safety of fluoroquinolones have made them attractive for the treatment of community-acquired and nosocomial infections. Prulifloxacin is a new fluoroquinolone antibacterial agent with a broad spectrum of activity against Gram-positive and -negative bacteria. Prulifloxacin is available for oral use, and after absorption is metabolized in to the active form, ulifloxacin. It exhibits good penetration in target tissues and a long elimination half-life, allowing once-daily administration. A number of randomized, controlled clinical trials carried out in Europe demonstrated the efficacy of prulifloxacin in the treatment of urinary tract (acute uncomplicated and complicated) and respiratory tract infections (acute exacerbations of chronic bronchitis), in comparison with the most widely used drugs such as ciprofloxacin, co-amoxiclav and pefloxacin. Prulifloxacin was generally well tolerated. The most frequent adverse reactions observed in clinical trials were gastric pain, diarrhea, nausea and skin rash. This review focuses on the characteristics of prulifloxacin, summarizing the relevant preclinical and clinical data.

Anti-Bacterial Agents↗
PubMed2005

Comparative study of Escherichia coli virulence determinants in strains causing urinary tract bacteremia versus strains causing pyelonephritis and other sources of bacteremia.

To assess the role of phylogenetic background and putative virulence factors (VFs) in Escherichia coli causing urinary bacteremia, 50 strains isolated from this condition were compared with 50 strains isolated from pyelonephritis and 50 from other sources of bacteremia. papA and papGII were significantly more prevalent in urinary bacteremia and pyelonephritis (78%, 66% and 70%, 58%) than in other-source bacteremia (48% and 24%), whereas sfa/focDE and cnf1 were more prevalent in urinary-source bacteremia (56% and 44%) than in pyelonephritis and other-source bacteremia (28%, 42% and 20%, 28%). Group B2 was the most frequent in all conditions (63% of isolates) and exhibited the greatest concentration of VFs. Urinary tract bacteremia, pyelonephritis, and other-source bacteremia isolates presented similar virulence scores (7.8, 7.0, and 6.6); however, there were striking differences among the phylogenetic groups (8.7 in group B2 versus 3.4 in group A; P < .001). Group A and B1 strains almost exclusively infected compromised hosts.

Bacteremia↗
PubMed2004

Rapid and specific detection of the O15:K52:H1 clonal group of Escherichia coli by gene-specific PCR.

Primers specific for Escherichia coli O15:K52:H1 were devised based on a novel single-nucleotide polymorphism identified within the housekeeping gene fumC, i.e., G594A. In experiments comparing various reference typing methods, the new primers provided 100% sensitivity and specificity for the O15:K52:H1 clonal group, including 162 diverse clinical and reference E. coli isolates.

Base Sequence↗
PubMed2004

Bacteriophages and diffusion of beta-lactamase genes.

We evaluated the presence of various Beta-lactamase genes within the bacteriophages in sewage. Results showed the occurrence of phage particles carrying sequences of bla(OXA-2), bla(PSE-1) or bla(PSE-4) and bla(PSE)-type genes. Phages may contribute to the spread of some Beta-lactamase genes.

Amino Acid Sequence↗
PubMed2003

Shiga toxin 2-converting bacteriophages associated with clonal variability in Escherichia coli O157:H7 strains of human origin isolated from a single outbreak.

Shiga toxin 2 (Stx2)-converting bacteriophages induced from 49 strains of Escherichia coli O157:H7 isolated during a recent outbreak of enterocolitis in Spain were examined in an attempt to identify the variability due to the stx(2)-converting phages. The bacterial isolates were divided into low-, medium-, and high-phage-production groups on the basis of the number of phages released after mitomycin C induction. Low- and medium-phage-production isolates harbored two kinds of phages but released only one of them, whereas high-phage-production isolates harbored only one of the two phages. One of the phages, phi SC370, which was detected only in the isolates with two phages, showed similarities with phage 933W. The second phage, phi LC159, differed from phi SC370 in morphology and DNA structure. When both phages were present in the same bacterial chromosome, as occurred in most of the isolates, only phi SC370 was detected in the supernatants of the induced cultures. If phi LC159 was released, its presence was masked by phi SC370. When phi SC370 was absent, large amounts of phi LC159 were released, suggesting that there was some regulation of phage expression between the two phages. To our knowledge, this is the first description of clonal variability due to phage loss. The higher level of phage production was reflected in the larger amounts of Stx2 toxin produced by the cultures. Some relationship between phage production and the severity of symptoms was observed, and consequently these observations suggest that the virulence of the isolates studied could be related to the variability of the induced stx(2)-converting phages.

Base Sequence↗
PubMed2002

Prevalence of clinical isolates of Escherichia coli producing inhibitor-resistant beta-lactamases at a University Hospital in Barcelona, Spain, over a 3-year period.

About 7% of 7,252 nonduplicated clinical Escherichia coli strains from a Spanish hospital showed reduced susceptibility to amoxicillin-clavulanate. Of these, 0.37% produced the IRTs TEM-30, TEM-31, TEM-33, TEM-34, TEM-37, TEM-40, TEM-51, and TEM-54; 5.3% were probable class C beta-lactamase overproducers; 0.8% were probable TEM-1 hyperproducers; 0.18% produced OXA-30; 0.15% overexpressed SHV-1; and 0.03% produced a PSE-1 enzyme.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed2002

Novel complex sul1-type integron in Escherichia coli carrying bla(CTX-M-9).

For the present report, a novel complex class 1 integron, In60, was characterized. Part of this integron includes the bla(CTX-M-9) gene and its downstream nucleotide sequence, which shares 81% and 78% nucleotide identity with those of kluA-1 beta-lactamase and orf3 of K. ascorbata, respectively. Furthermore, a new insertion sequence, IS3000, has been found in In60. PCR analysis indicates that integron In60 is present in 33 of 34 nonclonal enterobacterial isolates carrying the putative beta-lactamase CTX-M-9.

Base Sequence↗
PubMed2002

Global molecular epidemiology of the O15:K52:H1 extraintestinal pathogenic Escherichia coli clonal group: evidence of distribution beyond Europe.

Escherichia coli O15:K52:H1 is a significant extraintestinal pathogen in Europe (G. Prats et al., J. Clin. Microbiol. 38:201-209, 2000). To search for evidence of this clonal group outside of Europe, 75 non-European E. coli isolates of serogroup O15 were compared with five members of the O15:K52:H1 clonal group from Barcelona, Spain, according to genomic background, virulence genotypes, and antimicrobial resistance profiles. Amplification phylotyping showed that 16 (21%) of the 75 non-European O15 isolates corresponded with the O15:K52:H1 clonal group. The 16 non-European O15:K52:H1 clonal group members represented diverse geographic locales. They were isolated almost exclusively from humans with extraintestinal infections and accounted for 50% of all O15 isolates from five human clinical collections studied. Most non-European clonal group members exhibited a consensus virulence factor profile that included the F16 or F7-2 papA alleles (P fimbrial structural subunit), papG allele II (P fimbrial adhesin), iha (putative adhesin siderophore), and iutA (aerobactin receptor). This resembles the virulence profiles of (i) European representatives of the O15:K52:H1 clonal group and (ii) phylogenetically related "clonal group A," a recently recognized significant contributor to trimethoprim-sulfamethoxazole resistance in the United States (A. R. Manges et al., N. Engl. J. Med. 345:1007-1013, 2001). Antimicrobial resistance profiles were variable, and resistance was inconsistently transferred by conjugation. These findings indicate that the O15:K52:H1 clonal group is broadly distributed beyond Europe, exhibits previously unrecognized phenotypic and genotypic diversity, and contributes significantly to extraintestinal infections in humans.

Animals↗
PubMed1996

Endemic meningococcal disease in Cerdanyola, Spain, 1987--93: molecular epidemiology of the isolates of Neisseria meningitidis.

OBJECTIVE: To establish the relationships between 30 Neisseria meningitidis strains isolated in Cerdanyola (Spain) from 30 out of 36 sporadic cases of meningococcal disease (MD) during 1987--93 and their spread in this population by multilocus enzyme electrophoresis (MEE) and by pulsed-field gel electrophoresis (PFGE), and to evaluate the usefulness of PFGE versus serologic typing methods and MEE as an alternative epidemiologic marker to study meningococcal infection. METHODS: Serotyping, electrophoretic mobility of seven isoenzymes determined by MEE and chromosomal DNA macrorestriction with NheI resolved by PFGE were analyzed. RESULTS: Of these 30 strains, 25 were serogroup B and the remaining five were serogroup C, with the 4:P1.15 and the 2b:NT as the most common antigenic phenotypes, respectively. There were 13 electrophoretic types (ETs) by MEE, with 14 isolates showing an identical ET, 8. Sixteen pulse types (PTs) were generated by PFGE. The 14 ET 8 isolates were clustered into six PTs, A1, A2, A4, A5, A6 and A8. However, by combining both methods, 19 genetically distinct groups were obtained. Eleven of these groups (20 serogroup B strains) and two of these (four serogroup C strains) were genetically related. CONCLUSIONS: We conclude that, according to the clonal population structure, these 30 N. meningitidis strains are heterogeneous although a great number are related. Moreover, PFGE is a useful method to establish clonal structure in N. meningitidis strains under endemic conditions. Finer discrimination of these strains was achieved by combining both MEE and PFGE methods.

Journal Article↗