Enterococci antimicrobial resistance

Aerestrup F.M., Y. Agerso, P. Gemer-Smidt, M. Madsen, and L.B. Jensen (2000). Comparison of antimicrobial resistance phenotypes and resistance genes in Enterococcus faecalis and Enterococci faecium from humans in the community, broilers, and pigs in Denmark. Diagnostic Microbiology and Infectious Disease 37 127-137. 

Welton L.A., L.A. Thai, M.B. Perri, S. Donabedian, J. McMahon, J.W. Chow, and M.J. Zervos (1998). Antimicrobial resistance in enterococci isolated from turkey flocks fed virginiamycin. Antimicrobial Agents and Chemotherapy 42 705-708. 

Aarestrup FM, Seyfarth AM, Emborg HD, Pedersen K, Hendriksen RS, Bager F. Effect of abolishment of the use of antimicrobial agents for growth promotion on occurrence of antimicrobial resistance in fecal enterococci from food animals in Denmark. Antimicrob Agents Chemother 2001 45(7) 2054-9. 

There are a number of methods in use that directly detect the production of antimicrobial resistance in pathogens. /3 -Lactamase production can be detected rapidly and easily in the clinical laboratory with the use of nitrocephin disks. Nitrocephin is a chromogenic cephalosporin derivative that changes color on hydrolysis by /3-lactamase. Colonies from a growing bacterial culture can be touched to a disk, with /S-lactamase production noted within a few minutes. Although rapid and reliable, this method is limited to the assessment of strains of staphylococci, enterococci, H. influenzae, Moraxella catarrhalis, and N. gorwrrhoeae. The nitrocephin disk also cannot detect /3-lactam... 

The role of enterococci in nosocomial infections is probably due to a variety of factors of which antimicrobial resistance appears to be a primary cause. Enterococci possess a broad spectrum of both natural (intrinsic) resistance and acquired (transferable) resistance (Franz et al. 2003). Examples of antibiotics to which the enterococci present an intrinsic resistance include the P-lactam antibiotics (third generation cephalosporins), sulphonamides and clindamycin and aminoglycosides in low levels (Eranz et al. 2003). Acquired resistance based on plasmids or transpo-sons acquisition has relevance for chloramphenicol, erythromycin, high levels of clindamycin, aminoglycosides, tetracycline, high levels of P-lactam antibiotics, fluoroquinolones and glycopeptides like vancomycin (Murray 1990 Leclercq 1997). In particular, vancomycin-resistant enterococci (VRE) pose a major problem... 

Loguerdo C, Abbiati R, Rinaldi M, Romano A, Vecchio D, Blanco C, Coltorti M (1995) Longterm effects of Enterococcus faecium SF68 versus lactulose in the treatment of patients with cirrhosis and grade 1-2 hepatic encephalopathy. J Hepatol 23 39-46 Lopes MFS, Ribeiro T, Abrantes M, Marques JJF, Tenreiro R, Crespo MTB (2005) Antimicrobial resistance profiles of dairy and clinical isolates and type strains of enterococci. Int J Food Microbiol 103 191-198... 

Animals and humans constitute overlapping reservoirs of resistance, and consequently the use of antimicrobials in animals can have an impact on public health. For example, the occurrence of vancomycin-resistant enterococci in food-animals is associated with the use of avoparcin, a glyco-peptide antibiotic used as a feed additive for the growth promotion of animals. Vancomycin resistant enterococci and vancomycin resistance determinants can therefore spread from animals to humans. The bans on avoparcin and other antibiotics as growth promoters in the EU have provided scientists with a unique opportunity to investigate the effects of the withdrawal of a major antimicrobial with respect to the selective pressure on the occurrence and spread of antimicrobial resistance. Data shows that although the levels of resistance in animals and food, and consequently in humans, were markedly reduced after the termination of use, the effects on animal health and productivity were very minor. ° ... 

Antimicrobial resistance of major consequence may be detected, e.g., the test is very useful in detecting glycopeptide-resistant enterococci and glycopeptide-intermediate Staphylococcus aureus and slow-growing pathogens such as Mycobacterium tuberculosis. Furthermore, it can be used for detecting extended spectrum P-lactamases. In conclusion, the E-test is a simple, accurate and reliable method to determine the MIC for a wide spectrum of infectious agents [33, 34]. 

A major problem with antibiotics is that their overuse and improper use have led to the development of drug resistant bacteria and thus an increased number of infections with opportunistic bacteria, such as enterococci, coli-forms, pseudomonads, streptococci which are versatile and capable of becoming multidrug resistant. With this background, it may be said that searching for newer antimicrobial substances would be a promising line of research in the field of clinical microbiology. 

Quinupristin/dalfopristin, a new addition to the antimicrobial arsenal. Lancet 354 2012-2013 Kelkar P S, Li J T-C 2001 Cephalosporin allergy. New England Journal of Medicine 345 804—809 Moellering R C 1998 Vancomycin-resistant enterococci. Clinical Infectious Diseases 26 1196-1199... 

S. aureus and S. pyogenes account for the majority of community-acquired SSTIs. Data from the most recent SENTRY Antimicrobial Surveillance Program showed S.aureus to also be the most common cause (45.9%) of nosocomial SSTIs. Also of note in this study was the 30% incidence of methicillin resistance among strains of S. aureus. Other common nosocomial pathogens included Pseudomonas aeruginosa (11%), enterococci (8%), and E. coli (7%). ... 

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