Impact of empirical treatment in extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. bacteremia. A multicentric cohort study.

BACKGROUND: The objective of this study is to analyze the factors that are associated with the adequacy of empirical antibiotic therapy and its impact in mortality in a large cohort of patients with extended-spectrum ß-lactamase (ESBL)--producing Escherichia coli and Klebsiella spp. bacteremia. METHODS: Cases of ESBL producing Enterobacteriaceae (ESBL-E) bacteremia collected from 2003 through 2008 in 19 hospitals in Spain. Statistical analysis was performed using multivariate logistic regression. RESULTS: We analyzed 387 cases ESBL-E bloodstream infections. The main sources of bacteremia were urinary tract (55.3%), biliary tract (12.7%), intra-abdominal (8.8%) and unknown origin (9.6%). Among all the 387 episodes, E. coli was isolated from blood cultures in 343 and in 45.71% the ESBL-E was multidrug resistant. Empirical antibiotic treatment was adequate in 48.8% of the cases and the in hospital mortality was 20.9%. In a multivariate analysis adequacy was a risk factor for death [adjusted OR (95% CI): 0.39 (0.31-0.97); P = 0.04], but not in patients without severe sepsis or shock. The class of antibiotic used empirically was not associated with prognosis in adequately treated patients. CONCLUSION: ESBL-E bacteremia has a relatively high mortality that is partly related with a low adequacy of empirical antibiotic treatment. In selected subgroups the relevance of the adequacy of empirical therapy is limited.

[Pancreatic pseudocyst infection caused by Haemophilus parainfluenzae. Report of one case]. / Infección de pseudoquiste pancreático por Haemophilus parainfluenzae. Caso clínico.

We report a 48-year-old male admitted to hospital due to a severe alcoholic pancreatitis. At four weeks of evolution of the acute episode, an abdominal CAT scan showed a fluid collection of 20 cm diameter located in the pancreatic tail and 2 small collections in the head. The patient received several antimicrobials and during the seventh week of evolution, while receiving vancomycin, presented fever. A fine needle aspiration of the cyst revealed the presence of Haemophilus parainfluenzae biotype VIII. The patient was treated with amoxicillin-clavulanic acid and a laparoscopic cysto-gastrostomy, with a good clinical response.

Polymerase Chain Reaction Versus Blood Culture to Detect Candida Species in High-Risk Patients with Suspected Invasive Candidiasis: The MICAFEM Study.

INTRODUCTION: We evaluated the diagnostic reliability of serum polymerase chain reaction (PCR) versus blood culture, abdominal fluid or both (composite measure) in patients receiving empirical antifungal treatment for suspected invasive candidiasis. METHODS: This observational, prospective, non-interventional, multicentre study in Spain enrolled 176 critically ill patients admitted to the intensive care unit. Separate blood samples for culture and serum PCR were taken before the start of antifungal therapy. Patient assessment was performed according to each site's usual clinical practice. The primary end point was concordance between serum PCR and blood culture. Secondary end points were concordance between serum PCR and a positive abdominal fluid sample or the composite measure. Quality indices included sensitivity, specificity, positive/negative predictive values (PPV/NPV) and kappa indices. RESULTS: Among 175 evaluable patients, rates of Candida detection were similar for serum PCR (n = 16/175, 9.1%) versus blood culture (n = 14/175, 8.0%). Quality indices for serum PCR relative to blood culture were: sensitivity 21.4%; specificity 91.9%; PPV 18.8%; NPV 93.1%; kappa index 0.125. Thirty-two abdominal fluid samples were positive. Quality indices for serum PCR versus abdominal fluid were: sensitivity 31.3%; specificity 83.0%; PPV 15.6%; NPV 92.3%; kappa index 0.100. Quality indices for serum PCR versus the composite measure were: sensitivity 15.8%; specificity 92.7%; PPV 37.5%; NPV 79.9%; kappa index 0.107. CONCLUSION: The sensitivity of serum PCR for Candida detection was low and the rate of concordance was low between serum PCR and the other diagnostic techniques used to identify Candida infections. Hospital-based diagnostic tests need optimising to improve outcomes in patients with suspected invasive candidiasis. FUNDING: Astellas Pharma Inc.

Molecular characterization of a Spanish isolate of Mycobacterium malmoense.

We present the genomic characterization of a Spanish isolate of Mycobacterium malmoense. Identification and molecular characterization of the microorganism were performed using the technique of PCR-restriction fragment length polymorphism analysis (PRA) and sequencing of the 16S and the ITS spacer (16S-23S rDNA intergenic spacer region). It was seen that our isolate is very similar to the strain described in Sweden, but differs in the sequencing of the ITS from the isolate in Great Britain. Molecular techniques facilitate a rapid diagnosis and enable a better understanding of the epidemiology of this microorganism.

[Study investigating the activity of several fluoroquinolones against Pseudomonas aeruginosa using the mutant prevention concentration]. / Estudio de la actividad comparada de varias fluoroquinolonas frente a Pseudomonas aeruginosa mediante la determinación de la concentración preventiva de mutantes.

INTRODUCTION: The objective of this study was to compare the activity of ciprofloxacin, levofloxacin, moxifloxacin, gatifloxacin and ofloxacin against Pseudomonas aeruginosa by determining the mutant prevention concentration (MPC). METHODS: Thirty-four clinical isolates of Pseudomonas aeruginosa causing nosocomial infection were studied. MPC values were determined using an inoculum of 10(10) cfu/mL on Mueller-Hinton plates with serial dilutions of the antibiotics. The microorganisms were classified according to whether the patients had been previously treated with fluoroquinolones or not. RESULTS: The fluoroquinolone with the lowest MPC values was ciprofloxacin, followed by levofloxacin. Analysis of strains from patients previously treated with fluoroquinolones showed persistent susceptibility according to the CLSI criteria, but with lower activity of all the drugs. CONCLUSIONS: Although the microorganism remained susceptible to fluoroquinolones according to classical methods, the suitability of using these drugs in patients with severe infection and a history of fluoroquinolone use should be evaluated.

Infección de pseudoquiste pancreático por Haemophilus parainfluenzae: Caso clínico / Pancreatic pseudocyst infection caused by Haemophilus parainfluenzae: Report of one case

We report a 48-year-old male admitted to hospital due to a severe alcoholic pancreatitis. At four weeks of evolution of the acute episode, an abdominal CAT scan showed a fluid collection of 20 cm diameter located in the pancreatic tail and 2 small collections in the head. The patient received several antimicrobials and during the seventh week of evolution, while receiving vancomycin, presented fever. A fine needle aspiration of the cyst revealed the presence of Haemophilus parainfluenzae biotype VIII. The patient was treated with amoxicillin-clavulanic acid and a laparoscopic cysto-gastrostomy, with a good clinical response.

Criteria of time and antibiotic susceptibility in the elimination of duplicates when calculating resistance frequencies.

We studied the effects of various systems of eliminating repeat isolates on the absolute number and susceptibility of Pseudomonas aeruginosa, Acinetobacter baumannii and Staphylococcus aureus isolates over a 2 year period. The criterion of time is objective and reproducible, whereas that of variation in antibiotic susceptibility detects variations in the susceptibility of microorganisms that acquire resistance during treatment, but may be affected by methodological errors in determining the antibiotic susceptibility. These tools are useful in the control of multi-resistant bacteria and enable the true situation regarding antibiotic resistance in each geographical area to be determined.

Estudio de la actividad comparada de varias fluoroquinolonas frente a Pseudomonas aeruginosa mediante la determinación de la concentración preventiva de mutantes / Study investigating the activity of several fluoroquinolones against Pseudomonas aeruginosa using the mutant prevention concentration

Introducción. La finalidad de este estudio es comparar la actividad de ciprofloxacino, levofloxacino, moxifloxacino, gatifloxacino y ofloxacino frente a Pseudomonas aeruginosa mediante la determinación de la concentración preventiva de mutantes. Métodos. Se estudiaron 34 aislados clínicos de P. aeruginosa productores de infecciones nosocomiales. La determinación de la concentración preventiva de mutantes (CPM) se realizó mediante el inóculo de 10 10 UFC/ml en placas de Mueller-Hinton con concentraciones seriadas de antibióticos. Los microorganismos se agruparon en función de si el paciente había recibido tratamientos previos con fluoroquinolonas. Resultados. La fluoroquinolona que presenta menores valores de CPM es ciprofloxacino, seguida de levofloxacino. Al analizar las cepas de pacientes con tratamientos previos con fluoroquinolonas, se observa que aunque las cepas siguen siendo sensibles según los criterios del Clinical and Laboratory Standards Institute (CLSI), todos los fármacos muestran menos actividad. Conclusiones. Aunque el microorganismo sea sensible a las fluoroquinolonas por los métodos clásicos, debe valorarse la idoneidad de administrar tratamientos con estos compuestos en infecciones graves si el enfermo ha sido previamente tratado con ellos (AU)

Introduction. The objective of this study was to compare the activity of ciprofloxacin, levofloxacin, moxifloxacin, gatifloxacin and ofloxacin against Pseudomonas aeruginosa by determining the mutant prevention concentration (MPC). Methods. Thirty-four clinical isolates of Pseudomonas aeruginosa causing nosocomial infection were studied. MPC values were determined using an inoculum of 10 10 cfu/mL on Mueller-Hinton plates with serial dilutions of the antibiotics. The microorganisms were classified according to whether the patients had been previously treated with fluoroquinolones or not. Results. The fluoroquinolone with the lowest MPC values was ciprofloxacin, followed by levofloxacin. Analysis of strains from patients previously treated with fluoroquinolones showed persistent susceptibility according to the CLSI criteria, but with lower activity of all the drugs. Conclusions. Although the microorganism remained susceptible to fluoroquinolones according to classical methods, the suitability of using these drugs in patients with severe infection and a history of fluoroquinolone use should be evaluated (AU)