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Renew interest and enthusiasm for anaerobes stem from both technological improvements (culture media, production of an adequate anaerobic atmosphere, identification methods) and greater awareness on the part of clinicians. Anaerobic infections were historically treated empirically, targeting the species known to be involved in each type of infection. Prevotella, fusobacteria, and Gram-positive cocci (GPAC) were considered responsible for infections above the diaphragm whereas for intra-abdominal infections, Bacteroides of the fragilis group (BFG), GPAC and clostridia were predominantly implicated. The antibiotic susceptibility of anaerobes was only taken into consideration by the clinician in the event of treatment failure or when faced with infections by multidrug-resistant bacteria (MDR). The evolution of antibiotic resistance together with clinical failures due to the absence of detection of hetero-resistant clones has resulted in a greater need for accessible antibiotic susceptibility testing (AST) and disc diffusion method. Improved isolation and identification of anaerobes, along with the availability of accessible and robust methods for performing AST, will ensure that treatment, whether empirical or guided by an antibiogram, will lead to better outcomes for anaerobic infections. [ABSTRACT FROM AUTHOR]

Abstract Background Meropenem is a carbapenem that has an excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The major objective of the present study was to assess the in vitro activity of meropenem compared to imipenem and piperacillin/tazobactam, against 1071 non-repetitive isolates collected from patients with bacteremia (55%), pneumonia (29%), peritonitis (12%) and wound infections (3%), in 15 French hospitals in 2006. The secondary aim of the study was to compare the results of routinely testings and those obtained by a referent laboratory. Method Susceptibility testing and Minimum Inhibitory Concentrations (MICs) of meropenem, imipenem and piperacillin/tazobactam were determined locally by Etest method. Susceptibility to meropenem was confirmed at a central laboratory by disc diffusion method and MICs determined by agar dilution method for meropenem, imipenem and piperacillin/tazobactam. Results Cumulative susceptibility rates against Escherichia coli were, meropenem and imipenem: 100% and piperacillin/tazobactam: 90%. Against other Enterobacteriaceae, the rates were meropenem: 99%, imipenem: 98% and piperacillin/tazobactam: 90%. All Staphylococci, Streptococci and anaerobes were susceptible to the three antibiotics. Against non fermeters, meropenem was active on 84-94% of the strains, imipenem on 84-98% of the strains and piperacillin/tazobactam on 90-100% of the strains. Conclusions Compared to imipenem, meropenem displays lower MICs against Enterobacteriaceae, Escherichia coli and Pseudomonas aeruginosa. Except for non fermenters, MICs90 of carbapenems were Enterobacteriaceae and Acinetobacter but not P. aeruginosa. Some discrepancies were noted between MICs determined by Etest accross centres and MICs determined by agar dilution method at the central laboratory. Discrepancies were more common for imipenem testing and more frequently related to a few centres. Overall MICs determined by Etest were in general higher (0.5 log to 1 log fold) than MICs by agar dilution.

The article presents a study which discusses nimH, a novel nitroimidazole resistance gene contributing to metronidazole resistance in Bacteroides fragilis. Topics include plymerase chain reaction (PCR) amplification with NIM-3/NIM-5 primers yielded in both isolates; phylogenetic trees based on partial Nim amino acid sequences; and location of putative promotor sequence of nimH within IS614B.

Background: Meropenem is a carbapenem that has an excellent activity against many gram-positive and gramnegative aerobic, facultative, and anaerobic bacteria. The major objective of the present study was to assess the in vitro activity of meropenem compared to imipenem and piperacillin/tazobactam, against 1071 non-repetitive isolates collected from patients with bacteremia (55%), pneumonia (29%), peritonitis (12%) and wound infections (3%), in 15 French hospitals in 2006. The secondary aim of the study was to compare the results of routinely testings and those obtained by a referent laboratory. Method: Susceptibility testing and Minimum Inhibitory Concentrations (MICs) of meropenem, imipenem and piperacillin/tazobactam were determined locally by Etest method. Susceptibility to meropenem was confirmed at a central laboratory by disc diffusion method and MICs determined by agar dilution method for meropenem, imipenem and piperacillin/tazobactam. Results: Cumulative susceptibility rates against Escherichia coli were, meropenem and imipenem: 100% and piperacillin/tazobactam: 90%. Against other Enterobacteriaceae, the rates were meropenem: 99%, imipenem: 98% and piperacillin/tazobactam: 90%. All Staphylococci, Streptococci and anaerobes were susceptible to the three antibiotics. Against non fermeters, meropenem was active on 84-94% of the strains, imipenem on 84-98% of the strains and piperacillin/tazobactam on 90-100% of the strains. Conclusions: Compared to imipenem, meropenem displays lower MICs against Enterobacteriaceae, Escherichia coli and Pseudomonas aeruginosa. Except for non fermenters, MICs90 of carbapenems were <4 mg/L. Piperacillin/tazobactam was less active against Enterobacteriaceae and Acinetobacter but not P. aeruginosa. Some discrepancies were noted between MICs determined by Etest accross centres and MICs determined by agar dilution method at the central laboratory. Discrepancies were more common for imipenem testing and more frequently related to a few centres. Overall MICs determined by Etest were in general higher (0.5 log to 1 log fold) than MICs by agar dilution. [ABSTRACT FROM AUTHOR]

In anaerobic infections, the relationship between clinical failure and antibiotic resistance is difficult to demonstrate, especially in mixed anaerobic-aerobic infections. Single isolates of anaerobes in cases of bacteraemia revealed that treatment failures were due to inappropriate therapy. We review here cases, where the empiric treatment was unsuccessful due to resistance of anaerobic bacteria to the administered agents and where the change of the antibiotic allowed the patients to be cured. Many therapeutic failures could be linked to the lack of timely detection of resistance, including heteroresistance of the anaerobes. Disk diffusion or Etest methodology may be suitable, at least for rapidly growing anaerobes, to detect both resistance and heteroresistance to antibiotics widely used for empirical therapy. • Role of antibiotic resistance is difficult to demonstrate in mixed infections. • Empirical therapy of anaerobic bacteremia may be unsuccessful. • Unsuccessful empirical therapy is linked to resistance in anaerobes. • Disk diffusion test or Etest can detect heteroresistance in the anaerobes. [ABSTRACT FROM AUTHOR]

Introduction Recovery of the bacteria responsible for prosthetic joint infections is a major problem, which is due in part to the alteration of their ability to grow by storage during transportation to the laboratory. Methods In this prospective study, we assessed the benefit of inoculating an enriched liquid medium (Rosenow's broth) with intraoperative samples from 72 patients with prosthetic joint revision due to infection. We compared the results of culture of specimens collected in a standard receptacle with the results for specimens collected in Rosenow's broth. Results and interpretation 144 samples were taken by each of the 2 collection methods for subsequent culture. Concordance between standard and Rosenow samples was observed for 52 of the 58 strains cultured on agar and for 42 of the 97 strains (p Propionibacterium acnes, but also coagulase-negative staphylococci and streptococci. ? [ABSTRACT FROM AUTHOR]

Minimal inhibitory concentrations of moxifloxacin were compared with those of ofloxacin, ciprofloxacin, clindamycin, metronidazole and six β-lactams for 159 anaerobes isolated from human clinical samples. Unlike other fluoroquinolones, moxifloxacin demonstrated high activity against the 76 strains of the Bacteroides fragilis group as the minimal inhibitory concentration50 was 0.5 mg/l. Porphyromonas, Prevotella, Fusobacterium and Gram-positive anaerobic cocci were inhibited by 1 mg/l or less of moxifloxacin. It inhibited 93.7, 94.9 and 98% of the 159 strains investigated at concentrations of 1, 2 and 4 mg/l, respectively. Moxifloxacin was more potent than ofloxacin and ciprofloxacin against Gram-positive rods and anaerobic cocci. Its broad anaerobic spectrum in vitro is promising for the treatment of intra-abdominal and respiratory infections. [Copyright &y& Elsevier]

Seventeen diabetic patients with moderate to mild foot lesions associated with 20 osteomyelitic bones diagnosed by both bone scan and bone biopsy received rifampicin plus ofloxacin for a median duration of 6 months. Cure was defined as disappearance of all signs and symptoms of infection at the end of the treatment and absence of relapse during follow up. At the end of the treatment period, cure was achieved in 15 patients (88.2%) and was maintained in 13 patients (76.5%) at the end of an average post-treatment follow-up of 22 months. No serious drug-related adverse events were recorded. [ABSTRACT FROM AUTHOR]

We report the first case of intrafamily transmission of a C-MRSA clone harbouring toxic shock syndrome toxin-1 (TSST-1). Because of the risk of this clone to spread in the community, family members of these patients should be screened to detect and prevent the diffusion of recurrent or new infections. [ABSTRACT FROM AUTHOR]

Abstract: In this report, we review one case of bacteremia infection due to Dialister pneumosintes. The patient was admitted in post-partum with vaginosis and suppurative thrombosis of the ovarian veina. D. pneumosintes was isolated in pure culture from the three blood culture flasks. Identification of this bacterium was difficult and requires the amplification and partial sequencing of the 16S rRNA gene. The patients had favorable outcome after antibiotic treatment. [Copyright &y& Elsevier]

Describes a case of melioidotic osteomyelitis of the femur occurring in an Asian traveler. Treatment administered to the traveler; Bacillus that causes osteomyelitis; Risk of acquiring the disease in developing countries.

Abstract: The activity of telithromycin and comparator antibacterials was examined in isolates of Streptococcus pneumoniae and Haemophilus influenzae isolated from patients with community-acquired pneumonia (CAP), acute exacerbations of chronic bronchitis (AECB), or sinusitis during year 5 (2003–2004) of the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin global resistance surveillance study. Among S. pneumoniae, penicillin nonsusceptibility and erythromycin resistance were 35.7% and 36.0%, respectively. β-Lactamase was produced by 12.3% of H. influenzae isolates. β-Lactamase–negative ampicillin-resistant strains, mainly from Japan, comprised 5.2% of global H. influenzae isolates. Telithromycin and levofloxacin were the most active agents tested against S. pneumoniae and H. influenzae (>99% of isolates susceptible) isolated from patients with CAP, AECB, or bacterial sinusitis. Amoxicillin–clavulanate, levofloxacin, and telithromycin were the most active agents against multidrug-resistant S. pneumoniae. [Copyright &y& Elsevier]

Minimal inhibition concentrations (MICs) were determined for linezolid (LZD) and compared with those of reference antibiotics against 265 anaerobes. For the Bacteroides fragilis group, MIC range for LZD was 2–4 mg/l. Strains resistant to the other antibiotics were detected including one strain of B. fragilis showing high level resistance to metronidazole (64 mg/l). LZD MIC50 was 4 mg/l for prevotella and 1 mg/l for fusobacteria. LZD MICs were <1 mg/l for porphyromonas and veillonellae and ≤4 mg/l for all Gram-positive anaerobes. For all anaerobes, resistance rates were 1, 2.4, 9.8 and 17% for imipenem, amoxycillin–clavulanic acid, metronidazole and clindamycin, respectively. As no strains resistant to LZD were detected, this antibiotic seems a promising candidate to treat infections caused by anaerobes. [Copyright &y& Elsevier]

Of 69 clinical isolates of Finegoldia magna tested, 36% presented high-level MICs of erythromycin (>256 μg/ml), harboring erm (A) (n = 20) or erm (B) (n=5). Of nine isolates exhibiting an inducible resistance phenotype to macrolides-lincosamides-streptogramins B, four (44%) were susceptible with a potential risk of treatment failure due to emergence of resistant mutants. • Twenty-five (36%) isolates of F. magna were highly resistant to erythromycin. • All harbored an erm (A) subclass erm (TR) gene (80%) or an erm (B) gene (20%). • They exhibited a constitutive (64%) or an inducible MLS B phenotype (36%). • Clindamycin resistance was found in 84% of erythromycin-resistant isolates. • For isolates with an inducible MLS B phenotype, 44% were susceptible to clindamycin. [ABSTRACT FROM AUTHOR]