Genetic methods for detection of antimicrobial resistance

Abstract

Sundsfjord A, Simonsen GS, Haldorsen BC, Haaheim H, Hjelmevoll SO, Littauer P, Dahl KH. Genetic methods for detection of antimicrobial resistance. APMIS 2004;112:815-37.Accurate and rapid diagnostic methods are needed to guide antimicrobial therapy and infection control interventions. Advances in real-time PCR have provided a user-friendly, rapid and reproducible testing platform catalysing an increased use of genetic assays as part of a wider strategy to minimize the development and spread of antimicrobial-resistant bacteria. In this review we outline the principal features of genetic assays in the detection of antimicrobial resistance, their advantages and limitations, and discuss specific applications in the detection of methicillin-resistant Staphylococcus aureus, glycopeptide-resistant enterococci, aminoglycoside resistance in staphylococci and enterococci, broad-spectrum resistance to b-lactam antibiotics in gram-negative bacteria, as well as genetic elements involved in the assembly and spread of antimicrobial resistance.

GENETIC METHODS FOR DETECTION OF ANTIBIOTIC RESISTANCE: FOCUS ON EXTENDED-SPECTRUM Β-Lactamases

“…However, they can be helpful in providing explanations for unusual, complex antibiograms, confirming specific resistance mechanisms and in rapid identification and detection of resistance mechanisms in slow-growing organisms such as Mycobacterium tuberculosis. These modern methods have great potential for epidemiological studies that monitor the spread of resistant strains and mobile genetic elements in human or animal populations [6][7][8] .…”

“…A large number of interesting reviews on molecular detection of antimicrobial resistance have been published [5][6][7] . These describe the principles and practical applications of the most frequently reported genetic methods for assessing the presence of resistance genes or detection of mutations associated with antimicrobial resistance.…”

Antibiotic Resistance in Staphylococcus Species of Animal Origin

“…Microarray technology enables detection of a large number of resistance genes in a single experiment and has the potential for significant automation in a microchip format. However, a costeffective and user-friendly format for application in antimicrobial susceptibility testing remains to be developed (Sundsfjord et al, 2004). There are many examples of the use of DNA microarray for detection of antibiotic resistance genes in staphylococcal (Cui et al, 2005;Frye et al, 2006;Garneau et al, 2010;Monecke et al, 2007;Zhu et al, 2007a).…”

“…This is particularly important for difficultto-culture organisms; (v) Reduction in detection time of slow growth of the organism; (vi) More precise and fast therapeutic predictions; (vii) Minor biohazard risk once it is not necessary to propagate by culture of a microorganism (Sundsfjord et al, 2004).…”

“…(iv) It may detect not clinically relevant resistance genotypes; (v) Mutations in primer binding sites can generate false-negative results; (vi) It presents low clinical sensitivity when performed directly on mixed microbial samples due to inhibition of nucleic acid amplification or a limited number of targets; (vii) Regulatory mutations that affect gene expression are not detected unless a quantitative measurement of the specific mRNA is targeted; (viii) Unlike for conventional culture-based susceptibility test methods, no standards exist for performing genetic testing methods (Sundsfjord et al, 2004).…”