Ned Tijdschr Geneeskd. 2000 Dec 30;144(53):2568-72.
[Vancomycin-resistant Enterococcus faecium outbreak in a nephrology ward]

[Article in Dutch]

van der Steen LF, Bonten MJ, van Kregten E, Harssema-Poot JJ, Willems R, Gaillard CA.

Universitair Medisch Centrum Utrecht, divisie Interne Geneeskunde, afd. Infectieziekten & Aids, Heidelberglaan 100, 3584 CX Utrecht.

In April 2000, an outbreak of vancomycin-resistant Enterococcus faecium (VRE) was discovered in an internal medicine/nephrology and dialysis ward of the Eemland Hospital, Amersfoort, the Netherlands. Although enterococci are considered relatively non-virulent, VRE are resistant to almost all commercially available antibiotics. Surveillance cultures were obtained from all patients at the ward, all patients visiting the dialysis ward and the environment of patients. VRE were determined and clustering of strains was analysed using molecular genotyping. In all, 12 patients were colonized with the outbreak strain. Transmission of VRE usually occurs via the hands of health care workers. The ward was closed for new admissions, patients were divided in cohorts of colonized and non-colonized patients, and rooms were disinfected after patient discharge. Infection control measures (such as handwashing and use of gloves and gowns) were enforced and prescriptions of vancomycin and cephalosporins were reduced. With these measures the outbreak could be controlled. Epidemiological analysis demonstrated that earlier admission and previous use of ciprofloxacin, amoxicillin and amoxicillin-clavulanic acid were risk factors for colonization. A nearby hospital was a possible source of this outbreak.

Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11191795&dopt=Abstract antibiotic amoxicillin

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Thiamphenicol-glycinate-acetylcysteinate (TGA; CAS 20192-91-0) is widely used for the treatment of infections of varied aetiology. The aim of this study was to compare the antibacterial activity of thiamphenicol-glycinate (TG; CAS 15318-45-3), TGA, amoxicillin (CAS 61336-70-7) plus clavulanic acid (CAS 58001-44-8), azithromycin (CAS 83905-01-5) and ceftriaxone (CAS 104376-79-6). Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined against Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus pyogenes, Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae according to the National Committee for Clinical Laboratory Standards (NCCLS) methods. The effects of changes in assay conditions were also examined. The activity of TG and TGA was similar to that of amoxicillin plus clavulanic acid, with the exception of methicillin resistant S. aureus. Azithromycin and ceftriaxone were characterised by a limited activity against gram-positive cocci and methicillin resistant and cefinase-positive S. aureus, respectively. TG and TGA are characterized by a wide spectrum of activity, comparable to that of recent commercialized antibiotics for treatment of respiratory tract infections.

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Antimicrob Agents Chemother. 2001 Feb;45(2):589-92.
Comparative antianaerobic activity of BMS 284756.

Hoellman DB, Kelly LM, Jacobs MR, Appelbaum PC.

Departments of Pathology and Clinical Microbiology, Hershey Medical Center, Hershey, Pennsylvania 17033, USA.

Agar dilution MIC methodology was used to compare the activity of BMS 284756 with those of ciprofloxacin, levofloxacin, moxifloxacin, trovafloxacin, amoxicillin-clavulanate, piperacillin-tazobactam, imipenem, clindamycin, and metronidazole against 357 anaerobes. Overall, the respective MICs at which 50% of the isolates tested were inhibited (MIC(50)s) and MIC(90)s (in micrograms per milliliter) were as follows: BMS 284756, 0.5 and 2.0; ciprofloxacin, 2.0 and 16.0; levofloxacin, 1.0 and 8.0; moxifloxacin, 0.5 and 4.0; trovafloxacin, 0.5 and 2.0; amoxicillin-clavulanate, 0.5 and 2.0; piperacillin-tazobactam, 0.25 and 8.0; imipenem, 0.06 and 1.0; clindamycin, 0.25 and 8.0; and metronidazole, 1.0 and >16.0. BMS 284756 is a promising new quinolone with excellent antianaerobic activity.

Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11158759&dopt=Abstract antibiotic amoxicillin




Antimicrob Agents Chemother. 2000 Nov;44(11):3144-9.
ACI-1 from Acidaminococcus fermentans: characterization of the first beta-lactamase in Anaerobic cocci.

Galan JC, Reig M, Navas A, Baquero F, Blazquez J.

Servicio de Microbiologia, Hospital Ramon y Cajal, Instituto Nacional de Salud (INSALUD), 28034 Madrid, Spain.

Acidaminococcus fermentans belongs to the group of strictly anaerobic gram-negative cocci. All previously described Acidaminococcus strains are susceptible to beta-lactam antibiotics. An A. fermentans strain (RYC-MR95) resistant to penicillin and expanded-spectrum cephalosporin (amoxicillin and cefotaxime MICs, 64 microgram/ml) was isolated from a human perianal abscess. A fragment encoding a beta-lactamase from genomic DNA was cloned in Escherichia coli K-12 strain HB101, and the recombinant strain expressed resistance to amoxicillin (MIC, 1,024 microgram/ml) and cefotaxime (MIC, 4 microgram/ml). Clavulanic acid decreased the MICs to 8 and 0.03 microgram/ml, respectively. Analysis of the nucleotide sequence revealed a new class A beta-lactamase, ACI-1. In accordance with its biochemical properties, we propose to assign ACI-1 to functional group 2be. The ACI-1 enzyme (estimated pI 4.3) had <50% amino acid identity with any other class A beta-lactamases, the closest being ROB-1 from Haemophilus influenzae (44%). ACI-1 was closer to class A beta-lactamases from some gram-positive organisms (41 to 44% amino acid identity with Bacillus beta-lactamases) than to most class A enzymes from gram-negative organisms (TEM-1, 24.6%). The aci1 gene had a G+C content of 42.1%, in contrast with 56% G+C content for genomic DNA from A. fermentans, thus suggesting that aci1 may have been obtained by horizontal gene transfer.

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