|Prior to 1985|
Once relegated to the domain of research laboratories, molecular methods for the diagnosis of infectious disease had little, if any place, in a clinical diagnostic laboratory prior to 1985. Procedurally, molecular methods were very complex and required specialized instrumentation and dedicated laboratory space. They were also susceptible, initially, to the influence of variation of technique. Although they represented valuable research tools, and were helpful as esoteric testing for unique clinical situations, their performance characteristics simply did not fit well into most clinical laboratories.Certain pathogens were logical targets for development. Organisms that were of concern for significant patient populations, were difficult to sustain in transport, and/or were difficult to cultivate and detect by traditional methods represented some of the first targets of commercially offered molecular based assays.Sexually transmitted diseases, affecting significant numbers of people, with key pathogens affected by lability in transport or poor sensitivity with traditional cultivation or antigen detection methods, were among the first targets for development.
|Challenges for Implementation: Cost|
Implementing molecular methods may involve purchasing an equipment platform that represents a significant capital investment. Reagents for the assays are frequently more expensive, on a cost per test basis, than either culture or antigen detection methods. Reimbursement issues, although improving, can be more complex. Realistically, implementations of molecular methods are likely to represent increased costs that do need to be weighed against the potential benefits that can be realized.When considering the implementation of a molecular method, the following question should be asked:Will the methods significantly impact/improve clinical management and patient outcomes, reduce antimicrobial costs and lengths of stay, and/or facilitate infection control, epidemiology, or antibiotic stewardship programs?The answer may not be "yes" for every single agent of infectious disease for which molecular methods are now available.
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