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Juan J Picazo

Publications and source records attributed to Juan J Picazo.

At least 19 recordsLinked to original sources
PubMed2006

Antimicrobial activity of tigecycline against clinical isolates from Spanish medical centers. Second multicenter study.

The antimicrobial activity of tigecycline, a novel glycylcycline, was evaluated against 1102 bacterial isolates from 20 centers in Spain. The MIC of tigecycline at which 90% (MIC(90)) of the pneumococci tested were inhibited was the lowest (0.06 microg/mL) of all the antibiotics tested. The MICs of tigecycline against enterococci ranged from 0.03 to 0.125 microg/mL. All staphylococci were inhibited by < or =0.25 microg/mL of tigecycline, and 99.6% of Enterobacteriaceae isolates were inhibited by < or =2 microg/mL of tigecycline. Tigecycline demonstrated good activity against Bacteroides fragilis group organisms with an MIC(90) of 4 microg/mL. The results of this study confirm the excellent activity of tigecycline against multiresistant Gram-positive and Gram-negative pathogens.

Anti-Bacterial Agents↗
PubMed2006

Comparative in vitro activity and the inoculum effect of ertapenem against Enterobacteriaceae resistant to extended-spectrum cephalosporins.

The in vitro activity and the inoculum effect of ertapenem were evaluated against a total of 70 Enterobacteriaceae isolates resistant to extended-spectrum cephalosporins. The extended-spectrum beta-lactamase phenotypic confirmatory disk diffusion test was performed and AmpC-inducible species were detected using cefoxitin/cefotaxime disk antagonism tests. beta-Lactamases were characterised by isoelectric focusing and TEM-specific polymerase chain reaction. Minimum inhibitory concentrations (MICs) were determined by the National Committee for Clinical Laboratory Standards agar dilution method. Ertapenem showed excellent activity against almost all isolates tested, with MIC(50) and MIC(90) values of 0.03 mg/L and 0.12 mg/L, respectively. When the inoculum was increased 100-fold, susceptibility decreased from 98.6% to 65.7% for cefepime and from 75.7% to 54.3% for piperacillin/tazobactam, without changing for ertapenem. The data from this study suggest that this new carbapenem may be useful for treating mixed infections involving Enterobacteriaceae isolates resistant to third-generation cephalosporins.

Anti-Bacterial Agents↗
PubMed2006

In vitro activity of tigecycline (GAR-936) and other antimicrobials against tetracycline- and ciprofloxacin-resistant Campylobacter clinical isolates.

During 2003 in our hospital, 236 clinical faecal Campylobacter spp. were isolated, of which 166 (70%) were resistant to tetracycline and 199 (84%) were resistant to ciprofloxacin by the disk diffusion method. Resistance to both antimicrobial agents was found in 146 isolates (62%). The in vitro activity of tigecycline was compared with that of erythromycin, clindamycin and amoxicillin/clavulanic acid using the agar dilution method against 116 selected Campylobacter spp. that were resistant to both tetracycline and ciprofloxacin. The minimum inhibitory concentration at which 90% of the isolates were inhibited (MIC90) was 0.06 mg/L for tigecycline and 4, 2 and 1 microg/mL for amoxicillin/clavulanic acid, erythromycin and clindamycin, respectively. The high in vitro activity of tigecycline against tetracycline- and ciprofloxacin-resistant strains suggests a potential therapeutic role in the treatment of infections that involve Campylobacter spp.

Anti-Bacterial Agents↗
PubMed2006

[Antimicrobial resistance surveillance: VIRA STUDY 2006].

INTRODUCTION: The objective of this study was to determine the current antimicrobial susceptibility patterns of the most frequent multi-resistant bacteria and to analyze any possible changes with respect to the two VIRA studies carried out in 2001 and 2004. METHODS: In February 2006, the 40 participating hospitals sent the following microorganisms: non-penicillin-susceptible Streptococcus pneumoniae (92), methicillin-resistant Staphylococcus aureus (MRSA) (290), clinically significant coagulase-negative staphylococci (136), ampicillin-resistant Enterococcus faecium (89), ampicillin-resistant Haemophilus influenzae (67), ciprofloxacin-resistant Escherichia coli (365), Pseudomonas aeruginosa (181), and Acinetobacter baumannii (92). The hospitals provided epidemiological data on these microorganisms. Susceptibility was determined with a broth microdilution method. RESULTS: Among the non-penicillin-susceptible S. pneumoniae isolates, the proportion of those ones resistant to this antibiotic showed a significant (p < 0.001) decrease (59.8% in 2001, 30.2% in 2004 and 14.3% in 2006). Among MRSA, we detected one isolate nonsusceptible to linezolid, four resistant to quinupristin-dalfopristin and one strain with a vancomycin MIC of 4 microg/mL. The prevalence of extended-spectrum beta-lactamase-producing E. coli was 12.1%. Resistance of A. baumannii to imipenem varied from 27% in the 2001-2004 period to 47.8% in 2006 (p < 0.005). CONCLUSION: These results again emphasize that resistance surveillance systems are an important tool for preventing the emergence and spread of multi-resistant pathogens.

Acinetobacter baumannii↗
PubMed2005

Changing patterns of fluoroquinolone resistance among Bacteroides fragilis group organisms over a 6-year period (1997-2002).

The evolution of susceptibility to the newer fluoroquinolones, moxifloxacin and trovafloxacin, of Bacteroides fragilis group organisms isolated in our hospital from 1997 to 2002 was studied. A total of 927 strains were included in the study. Trovafloxacin was more active than moxifloxacin against the various species of the group. During the study period, an increase in resistance to both quinolones was observed. Rates of resistance to moxifloxacin at a breakpoint of 8 microg/mL remained stable at around 6% during the period 1997-1998 and increased to 11.4% in 2000 and to 16.5% in 2001-2002 (P<0.005). Resistance to trovafloxacin rose significantly from 0.6% in 1998 to 6.8% in 1999 (P<0.05) and did not change appreciably over the last 3 years studied. This study confirms the increasing resistance of B. fragilis group organisms to trovafloxacin and moxifloxacin and emphasizes the need to perform periodic antimicrobial susceptibility tests to guide the selection of appropriate antimicrobial therapy.

Anti-Infective Agents↗
PubMed2005

Management of the febrile neutropenic patient.

Fever of unknown origin in oncological patients is a frequent problem throughout the world. The microbiology of infections in these patients can vary widely. Gram-negative bacteria were more prevalent in early trials, but Gram-positive organisms have become increasingly common since the mid 1980s. However, Gram-negative microorganisms appear to be resurging. Equally important changes have occurred in the antimicrobial susceptibility of infective pathogens, most importantly methicillin-resistant Staphylococcus aureus, coagulase-negative staphylococci, vancomycin-resistant enterococci, viridans group streptococci, ciprofloxacin-resistant Escherichia coli and Pseudomonas aeruginosa. Current management strategies for febrile neutropenic patients emphasize risk assessment and the suitability of individual patients for outpatient versus hospital treatment and for oral versus parenteral therapy. Among the new determinants of infection risk, the most important are the severity and duration of neutropenia. Additional significant issues include: the selection of monotherapy versus combination therapy; and prophylaxis, which involves, among other strategies, quinolone use, prevention of fungal and viral infections, surveillance cultures, prevention of catheter-related infections, and vaccines. With relation to the consensus document, it should clearly define fever and neutropenia, and rank the strength of recommendations and the quality of the evidence on which they are based. Finally, the document should provide a detailed, stepwise management algorithm, addressing the initial empirical antimicrobial therapy and the antimicrobial therapy on days 3-5 and days 5-7 of therapy.

Anti-Bacterial Agents↗
PubMed2005

Differences in the DNA sequence of the translational attenuator of several constitutively expressed erm(A) genes from clinical isolates of Streptococcus agalactiae.

OBJECTIVES: To study the regulatory region of a constitutively expressed erm(A) gene in Streptococcus agalactiae clinical isolates. METHODS: Thirty clinical isolates of S. agalactiae which were cross-resistant to erythromycin and clindamycin and with a clindamycin MIC higher than that of erythromycin were studied by PCR, sequencing and molecular typing. RESULTS: PCR analysis revealed that all the strains harboured the erm(A) gene, either alone (26 isolates) or in combination with erm(B) (four isolates). Sequencing of the region upstream of erm(A) showed that all isolates possessed two types of genetic alteration. Most of the strains showed point mutations in the second leader peptide (mainly A137C) and, in four isolates (two clones), an insertion fragment with high homology to IS1381 and transposase genes was detected. Epidemiological analysis of strains indicated several clonal origins of isolates. CONCLUSIONS: The mutations described here are thought to result in increased or constitutive expression of the erm(A) gene.

5' Untranslated Regions↗
PubMed2005

Trends in nalidixic acid resistance in nontyphoidal Salmonella isolated from 1999 to 2002: decreased susceptibility to 6 fluoroquinolones.

We determined the resistance to nalidixic acid and 6 fluoroquinolones of 771 nontyphoidal Salmonella strains isolated from humans between 1999 and 2002. A total of 22 different serotypes were identified among the Salmonella isolates, the most common being Salmonella Enteritidis (79%) and Salmonella Derby (8%). Resistance to nalidixic acid increased from 38% in 1999 to 43% in 2002. This resistance was not homogeneous among the different serotypes, with the highest percentage of resistant isolates belonging to Salmonella Hadar (79%) followed by Salmonella Enteritidis (46%). Reduced ciprofloxacin susceptibility (minimal inhibitory concentrations [MICs] from 0.12 to 0.5 microg/mL) was observed in 300 (39%) Salmonella. In our study, the nalidixic acid-resistant strains had an MIC90 at least 4-fold higher than the susceptible ones for all the fluoroquinolones tested, thus showing that resistance to nalidixic acid is an indicator of low-level resistance to all fluoroquinolones.

Anti-Bacterial Agents↗
PubMed2005

In vitro activity of telithromycin against viridans group streptococci and Streptococcus bovis isolated from blood: antimicrobial susceptibility patterns in different groups of species.

The in vitro activities of penicillin, erythromycin, clindamycin, and telithromycin were determined against 155 viridans group streptococci (VGS) and 18 Streptococcus bovis blood isolates. Heterogeneity in the susceptibility patterns and macrolide resistance phenotypes and genotypes in the different groups of VGS was detected. We found seven telithromycin-resistant S. bovis isolates all harboring the erm(B) gene.

Animals↗
PubMed2004

Significance of nested PCR and quantitative real time PCR for cytomegalovirus detection in renal transplant recipients.

Immunocompromised renal transplant recipients are susceptible to severe cytomegalovirus (CMV) infection that makes its detection important in clinical practice. A total of 536 blood and 536 serum samples from 67 renal transplant recipients who had previously been diagnosed with terminal renal insufficiency were studied for CMV infection. In all samples, serology, shell vial culture, antigenaemia and nested polymerase chain reaction (PCR) in blood and serum were tested, and a real-time quantitative PCR was run on 90 specimens. Sixty-seven blood donors were used as controls. The results show that the quantitative real-time PCR assay could be of great interest for predicting CMV disease, and to monitor the onset of pre-emptive therapy.

Adult↗
PubMed2004

[Surveillance of antimicrobial resistance: VIRA study 2004].

INTRODUCTION: The objective of the study was to know the current situation of the antimicrobial sensitivity patterns of the main multi-resistant bacteria and to analyze any possible changes with respect to the VIRA study carried out in 2001. METHODS: The 40 participating hospitals sent a total of 1,425 microorganisms isolated in February 2004, distributed as follows: penicillin-resistant Streptococcus pneumoniae (139), methicillin-resistant Staphylococcus aureus (289), clinically significant coagulase-negative staphylococci (158), ampicillin-resistant Enterococcus faecium (89) and Enterococcus faecalis (2), ampicillin-resistant Haemophilus influenzae (85), ciprofloxacin-resistant Escherichia coli (346), Pseudomonas aeruginosa (187), and Acinetobacter baumannii (130). The hospitals provided epidemiological data on these microorganisms. Sensitivity was determined by the broth microdilution method. RESULTS: The number of highly penicillin-resistant pneumococci fell significantly (p < 0.0001) compared with the previous study (from 59.8% to 30.2%). Global methicillin-resistance in S. aureus was 31.2%, which represents a significant increase (p < 0.001) compared with the year 2001 (24.8%). 11.3% of the E. coli strains were extended-spectrum beta -lactamase-producers and came from 24 hospitals. One P. aeruginosa isolate gave a positive result in the E-test MBL assay, suggesting the presence of metallo-beta -lactamases. The strains of imipenem-resistant A. baumannii presented cross-resistance with several antibiotics. CONCLUSION: These results show how the multi-resistant bacteria included in the study represent a growing problem in our hospitals. This emphasizes the importance of resistance surveillance systems and the correct use of antimicrobial agents.

Acinetobacter baumannii↗
PubMed2003

[Epidemiologic study of infection by resistant gram-positive bacteria (G + R Study)].

INTRODUCTION: This epidemiologic study was performed to obtain the following information: incidence of the main multiresistant gram-positive microorganisms (coagulase-negative staphylococci, Staphylococcus aureus, Streptococcus pneumoniae and enterococci) in Spanish hospitals, the type of infections they cause and the most highly affected hospital areas, as well as some antimicrobial resistance patterns, specifically S. aureus to methicillin and S. pneumoniae to penicillin. METHODS. Among the various Spanish autonomous regions, 104 hospitals and 446 doctors belonging to several medical fields participated in the study. Patients admitted to the following departments were included: Intensive Care, Infectious Diseases, Internal Medicine, Hematology, Surgery, Pneumology, Oncology and Pediatrics. The study was performed between December 2000 and March 2001, using two one-week time periods. RESULTS: Staphylococci were the most frequently isolated microorganisms, comprising more than 70% of the etiologic agents found. Enterococci were responsible for 17 to 20% of the infections evaluated. Among the total, 35.3% of S. aureus were methicillin-resistant and 28.6% of pneumococci were penicillin-resistant. The most frequent infections were bacteremias, followed by skin and soft tissue infections, and lower respiratory tract infections. CONCLUSIONS: This study confirms the high percentage of methicillin-resistant S. aureus and penicillin-resistant S. pneumoniae present in our country. It also shows that among gram-positive microorganisms, there is a clear predominance of staphylococci as pathogenic agents.

Drug Resistance, Multiple, Bacterial↗
PubMed2003

[Respiratory infections in adults hospitalized in internal medicine and pneumology departments. DIRA (Adult Respiratory Infection Day) study].

INTRODUCTION: Respiratory tract infections (RIs) are frequent processes that can require hospitalization or affect already hospitalized patients. The Foundation for the Study of Infection has promoted the DIRA (Adult Respiratory Infection Day) Project, with the aim of investigating and assessing the impact of this problem, particularly in Internal Medicine and Pneumology Departments. METHODS: Prospective prevalence study involving 158 physicians in 100 Internal Medicine and Pneumology Departments. Data were collected on predetermined days, once every three months (total of four data sets) and included information on number of patients attended, number of patients with infection, and epidemiologic, clinical, microbiologic and treatment characteristics of patients with RI. RESULTS: A total of 3,596 patients were hospitalized at the four time points. Among these, 39.1% presented clinical symptoms consistent with infection and 34.3% of these were RIs. The mean age of RI patients was 65.6 years, 68.8% were males, 84.1% had an underlying disease (most frequently chronic obstructive pulmonary disease) and 25.1% had one or more predisposing factors. Pneumonia was the most frequent diagnosis (41.3% of RIs). RI was documented microbiologically in 15.8% of cases. Antibiotic treatment was applied in 99.7% of patients with acute bronchitis and 81.8% of those with upper respiratory tract infection; penicillins were the most frequent treatment. Data are presented by diagnosis. CONCLUSIONS: A substantial rate of respiratory infections was found in patients admitted to hospital Internal Medicine and Pneumology Departments, with pneumonia being the most frequent. There was a paucity of microbiologic documentation. It is likely that antibiotic treatment was not justified in the majority of patients with upper respiratory tract infections. A combination of two or more antimicrobial agents was used in about half of cases.

Adult↗
PubMed2003

[Respiratory infections outside the hospital. DIRA study].

INTRODUCTION: Most visits to the primary care center are for infection and particularly respiratory tract infection. Antimicrobial administration for these clinical processes is common and these agents are often used to treat viral infections. La Fundación para el Estudio de la Infección (Foundation for the Study of Infection) designed the DIRA (Día de la Infección Respiratoria del Adulto, Adult Respiratory Infection Day) Project to investigate and assess the impact of this problem. METHODS: The study design consisted of one-day cross sections with the participation of 720 physicians belonging to Primary Health Care Centers from the 17 Autonomic Regions of Spain, establishing a one-day cross section every three months for one year. Epidemiologic, clinical and therapeutic factors were evaluated. RESULTS: The total number of visits attended was 72 929, and 14 426 patients had infectious processes (43.9%). Among these, 9145 (63.4%) had a respiratory infection. The mean age of the patients was 44.6 years and 34.1% had an underlying condition. Common cold was the most frequent diagnosis. Antibiotics were prescribed in 53.2% of patients. Results were compared to those of a previous study. DISCUSSION: Infection in general and respiratory infection in particular is frequently attended in primary care. Antibiotics are widely used in our setting and self-medication is common.

Adolescent↗
PubMed2003

Distribution of tetracycline resistance genes tet(M), tet(O), tet(L) and tet(K) in blood isolates of viridans group streptococci harbouring erm(B) and mef(A) genes. Susceptibility to quinupristin/dalfopristin and linezolid.

Susceptibility to erythromycin, tetracycline, clindamycin, quinupristin/dalfopristin and linezolid was investigated using 111 consecutive non-duplicate blood culture isolates of viridans-group streptococci (VGS). The erm(B) and mef(A) genes were detected, either alone or in combination, in the 47 (42%) erythromycin-resistant strains. The tet(M) gene alone was predominant (78%) in the 36 (35%) tetracycline-resistant isolates. Two isolates carried the tet(O) gene alone and two others the tet(L) associated with tet(O) or tet(M). The association between erythromycin and tetracycline resistance was common and the erm(B) and tet(M) determinants seem to be associated in our VGS. We found three isolates resistant to quinupristin/dalfopristin, all of them were erythromycin and tetracycline-resistant. For all isolates tested, linezolid MICs were <or=2 mg/l.

Acetamides↗
PubMed2003

Staphylococcus aureus bacteremic pneumonia: differences between community and nosocomial acquisition.

OBJECTIVE: The aim of the study was to ascertain the clinical and epidemiologic characteristics of patients with nosocomial or community-acquired Staphylococcus aureus bacteremic pneumonia. METHODS: A prospective study of 134 cases diagnosed between January 1990 and December 1995 was performed. RESULTS: Fifty cases involved primary bacteremic pneumonias, of which 80% were nosocomial (the majority, 72%, in intensive care unit patients, of whom 57% were post-surgery). Of the 84 cases of secondary pneumonia, 36 were non-intravenous drug users (78% nosocomial, of whom 43% were in the intensive care unit), and 48 cases were intravenous drug users (98% community-acquired). CONCLUSIONS: Nosocomial S. aureus bacteremic pneumonia was especially frequent in intensive care unit patients (68.1%), and community-acquired pneumonia in intravenous drug users (72.3%). In non-intravenous drug users, clinical outcome and mortality were similar for nosocomial and community-acquired pneumonia.

Adult↗