Antimicrobial susceptibility of Helicobacter pylori to six antibiotics currently used in Spain.

BACKGROUND: Antibiotic resistance is directly related to the loss of efficacy of currently accepted Helicobacter pylori therapies. Knowledge of the antibiotic susceptibility in a local area can contribute to the design of specific 'à la carte' treatments. The aim of this study was to analyse the susceptibility of H. pylori isolates to six conventional antibiotics currently used in a northern region of Spain. METHODS: Seventy-one isolates were obtained from gastric biopsies of 76 consecutive adult patients suffering from peptic ulcer disease, dyspepsia or familial gastric cancer and known to be infected with H. pylori by conventional methods. Susceptibility testing was performed for amoxicillin, ciprofloxacin, levofloxacin, clarithromycin, metronidazole and tetracycline using the Etest method. RESULTS: The prevalence rates of resistance were as follows: amoxicillin, 1.4% [95% confidence interval (CI) 0.0-7.6]; clarithromycin, 14.7% (95% CI 7.3-25.4); ciprofloxacin, 14.3% (95% CI 7.1-24.7); levofloxacin, 14.5% (95% CI 7.2-25.0); metronidazole, 45.1% (95% CI 33.2-57.3); and tetracycline, 0% (95% CI 0.0-5.1). CONCLUSIONS: Our study confirms an increasing rate of resistance to levofloxacin that equals that of clarithromycin in our healthcare area. This fact may reflect a wide and indiscriminate use of the former antibiotic and could account for a loss of clinical effectiveness of levofloxacin-containing regimens. Moreover, clarithromycin resistance rates remain stable, which could allow us to maintain its use in our area.

Caracterización molecular de aislados clínicos de Pseudomonas aeruginosa productores de la metalobetalactamasa VIM-2 en Cantabria, España / Molecular characterization of Pseudomonas aeruginosa isolates in Cantabria, Spain, producing VIM-2 metallo-beta-lactamase

Introducción En España el aislamiento de cepas de Pseudomonas aeruginosa productoras de metalobetalactamasas (MBL) es poco frecuente. En este artículo se describe la caracterización de 9 aislados clínicos de P. aeruginosa multirresistentes clonalmente relacionados, aislados en Cantabria (España) que poseen el gen (..) (AU)

Introduction Pseudomonas aeruginosa strains producing (..) (AU)

[Molecular characterization of Pseudomonas aeruginosa isolates in Cantabria, Spain, producing VIM-2 metallo-beta-lactamase]. / Caracterización molecular de aislados clínicos de Pseudomonas aeruginosa productores de la metalobetalactamasa VIM-2 en Cantabria, España.

INTRODUCTION: Pseudomonas aeruginosa strains producing metallo-beta-lactamases (MbetaL) are uncommon in Spain. This study describes the characterization of 9 new clonally related multiresistant P. aeruginosa isolates possessing the bla(VIM-2) gene in Cantabria (Northern Spain). METHODS: P. aeruginosa clinical strains (1 per patient) were isolated in the Microbiology Service of Marqués de Valdecilla University Hospital between January 2004 and December 2006. Identification and preliminary susceptibility studies were performed with the MicroScan WalkAway system (Dade Behring, Sacramento, CA) and results were verified by a microdilution reference method. RESULTS: MICs of imipenem and meropenem for the 9 isolates ranged from 32 to 128 and 16 to 64 microg/mL, respectively. Nine isolates had a single Rep-PCR pattern and were intermediate or resistant to ceftazidime, cefepime, gentamicin, tobramycin, amikacin and ciprofloxacin. Eight of the 9 isolates were susceptible to aztreonam. Hydrolysis activity of imipenem in MbetaL-positive isolates ranged from 162+/-18 to 235+/-28 pmol/min/microg protein and was abolished in the presence of 5 mM EDTA. All isolates possessed an integron with genes aac(6')32, bla(VIM-2) and a putative transposase-encoding gene, flanked by the conserved 5'CS and 3'CS regions. CONCLUSION: In the clinical isolates studied, the presence of MbetaL VIM-2 sufficed to explain their resistance to carbapenems.

Isolation of Mycoplasma hominis in critically ill patients with pulmonary infections: clinical and microbiological analysis in an intensive care unit.

OBJECTIVE: Mycoplasma hominis is a well recognized extragenital pathogen. However, it is an uncommon cause of respiratory infections in critically ill patients admitted to the intensive care unit (ICU). DESIGN AND SETTING: Prospective clinical investigation in a 21-bed ICU in a university hospital. PATIENTS: Seven patients requiring intensive care who developed a ICU-acquired pneumonia in which M. hominis was recovered from bronchoalveolar lavage and pleural fluid cultures. INTERVENTIONS: M. hominis was isolated in all patients by use of conventional bacteriological cultures. All strains were identified by 16S rRNA gene sequencing analysis. Patients' charts were reviewed for each case of infection. RESULTS: Seven strains of M. hominis were isolated during a 4-year period. All of these isolates were recovered from adult men admitted to the ICU and all had clinical signs of pneumonia. In three patients treatment for M. hominis with quinolones was associated with a good clinical response. CONCLUSION: Suspicion of M. hominis pneumonia must be heightened particularly in critically ill patients. Therefore an understanding of the microbiology of this organism is essential to successfully treat patients with these infections that are not ordinarily covered with standard antibiotic therapy.

Pneumonia due to Mycoplasma hominis in a healthy adult.

A case of pneumonia due to Mycoplasma hominis in a healthy adult is presented. The bacterium was diagnosed by a quantitative culture method and identification to the species level by sequence analysis of 16S rRNA gene. The objective of this presentation is to bring to attention the need to search for this opportunistic pathogen. Mycoplasma may be an important cause of bacterial pneumonia without microbiological diagnosis and its incidence may be underestimated.