Lateral flow immunoassays – a new era of antimicrobial resistance detection

Antimicrobial resistance (AMR) is the biggest global threat to public health, with at least 1.27 million deaths attributed to antibiotic resistant bacteria.¹ Amongst those associated most with deaths include third-generation cephalosporin-resistant and carbapenem-resistant Enterobacterales, which cause life threatening infections with limited treatment options.

Of particular concern is the rise of carbapenemase-producing Enterobacteriaceae (CPE). Species belonging to this family include Escherichia coli, Klebsiella spp. and Enterobacter spp., which are some of the most common causes of infections. Acquisition of carbapenemases by these species means they are resistant to the last line of antibiotics used to treat them, such as ertapenem and meropenem. Treatment becomes challenging and morbidity and mortality increase. This places a heavy burden on the UK health system and a study estimated that a CPE outbreak where 40 patients were colonised or infected cost the NHS £1 million.^2,3 With these bacteria spreading rapidly in healthcare settings, intervention strategies are therefore crucial to prevent spread, limit financial costs and save patient lives.

In a routine microbiology workflow, detection of antimicrobial resistance is achieved through antibiotic sensitivity testing (AST) methods and/or direct identification of antibiotic resistance mechanisms. The latter is particularly important, as antibiotic susceptibility does not always correspond to the presence or absence of resistance mechanisms that, when undetected, can lead to inappropriate antibiotic use and spread of resistance. The OXA-48-like carbapenemases are a prime example of this, as low-level carbapenem resistance mediated by this class of enzymes has meant they can often go undetected, resulting in them now being the most common carbapenemase family isolated in the UK.⁴