HHE Infectious disease diagnostics | Page 8

8 | VALUE OF DIAGNOSTICS THROUGHOUT THE PATIENT PATHWAY | 2021
molecules , such as lipopolysaccharide , PCT is also produced by extra-thyroidal cells including immune and endothelial cells . 14 The detection of elevated levels of PCT using immunoassays has been demonstrated to be highly sensitive and specific for differentiating bacterial from viral infection and other inflammatory causes of systemic inflammatory response syndrome . Clinical trials have demonstrated that PCT can be safely used to help reduce the duration of antimicrobial therapy and even delay the prescribing of antibiotics in situations where a diagnosis of infection may not be clear . 15 IVDs such as PCT immunoassays are important additions to laboratory-based molecular methods in helping the clinician risk-stratify patients , determine whether a microbiological result is likely colonisation / contamination or significant , and guide the appropriate duration of treatment .
The future of IVDs for infectious diseases The ability to be able to miniaturise techniques behind molecular diagnostics , such as multiplex PCR , is driving the development of point-of-care microbiological testing . 16 Multiplex PCR has been demonstrated to be sensitive and specific for the identification of infective organisms and genotypic resistance mechanisms , providing rapid turn-around-times for organism identification and inference of phenotype . Linked with antimicrobial stewardship programmes , multiplex PCR can have a significant clinical impact on patient outcomes . 17 With advances in techniques such as loopmediated isothermal amplification ( LAMP ), multiplex PCR can be miniaturised and applied to lab-on-chip diagnostics to support organism identification and rapid detection of genotypic markers of antimicrobial resistance . 18 Lab-on-chip diagnostics have the potential to move molecular-based IVDs for infectious diseases away from traditional laboratories towards point-of-care / near-patient testing . This shift in IVDs will require a consideration of antimicrobial and diagnostic stewardship practices to ensure that the added value of these approaches is achieved . 7 This may include linkage with electronic clinical decision support systems ( CDSS ) and artificial intelligence , which have been developed in parallel to many of the advances in IVDs for infectious disease . 16
In addition to IVDs , advances in technology have facilitated the development of companion in vivo diagnostic approaches that are emerging to support the management of infectious diseases . Technologies such as aptamer-based biosensing and microneedle technology are supporting the exploration of in vivo methods of real-time monitoring of drugs and biomarkers . For example , in vivo monitoring of antimicrobial concentrations in blood and interstitial fluid using biosensors have been reported . 19 , 20 In vivo diagnostic approaches may eventually compliment many of our IVDs . The focus on development of technologies that can perform reliably in vivo is also likely to help advance technology used in IVDs and thus should not be seen as competition , but a natural evolution building on the successes of preceding diagnostics .
Conclusion IVDs are important in supporting the diagnosis and optimal treatment of infection . With advances in IVD technology , a greater focus on the value of diagnostic use and the information they provide is required . This will require greater linkage with antimicrobial and diagnostic stewardship programmes and additional technologies that are under development to ensure that appropriate support is provided to the end-user .
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