The future of infectious diagnostics

The ideal strategy for treating infectious diseases calls for patient specific and pathogen specific treatment with respect to minimizing development of antimicrobial resistance.
The current treatment strategy is a combination of empirical treatment followed by targeted treatment based upon results of diagnostic procedures.
The empirical treatment of severe disease is designed to be broad-spectrum in order to achieve coverage of (ideally) at least 95% of infections – but in most sites of the world not more than 50-60% coverage is achieved.
In spite of the broad-spectrum design of the initial empirical treatment, it is in fact “too narrow” in some patient populations leading to increased (and unnecessary) mortality in this population.
The switch to the more narrow-spectrum specific therapy depends upon the availability of specific diagnostics for the individual patient.
The diagnostics is traditionally based upon agar based culture in clinical microbiology laboratories and results are available to the clinician after several days.
Thus, in many parts of the world, traditional diagnostics will have little impact on clinical patient management decision, as the patient at the time of diagnostic result (hopefully) is improving, and therefore likely to continue on the efficient (but broad-spectrum) treatment.
Only in the case of failure of the initial empiric treatment, will a significant diagnostic impact on patient management be seen.
The consequence of this is unnecessary use of broad-spectrum antimicrobials is unwanted and escalating antimicrobial resistance rates – and unnecessary high mortality rates from severe infections.