Validation of the T5000/PLEX-ID for system for the identification of etiologic agents of respiratory infection 


Charlotte A. Gaydos heads up the project to validate a rapid, sensitive, specific and comprehensive platform capable of detecting various common pathogens, as well as atypical pathogens.



Febrile illnesses account for 10-20% of visits to emergency departments (ED). For many patients, fever represents a self-limiting and benign process. Occasionally, serious bacterial or viral respiratory tract infections may be present which can cause life threatening complications or death. The infectious agent may be one of a number of commonly occurring pathogens acquired in the community, or less frequently an atypical agent, or an emerging biothreat (BT) pathogen.

Of increasing concern, as well, is the potential patient who presents to the ED with a respiratory febrile illness who may be infected with a BT agent. Prompt directed therapy based on an identified pathogen is critical for optimizing patient outcome, and protecting public concerns.

Unfortunately, front line clinicians are currently limited in their ability to rapidly and reliably identify infectious agents. Bacterial and viral culture, the current "gold standard" assays for pathogen identification, is restricted by significant delays in reporting of results (24-48 hours for bacteria and even longer for viruses), and has relatively low sensitivity. These limitations result in physicians waiting for results of tests, or initiating empiric therapy. Potential problems associated with this approach include delayed treatment, improper choice of therapeutic agent, unnecessary use of antibiotics, and development of antibiotic resistance. In the case of atypical, emerging and BT agents, improper or delayed diagnosis has added costs associated with contagion and delayed recognition and management of public health threats.

Molecular based diagnostic methods have shown repeatedly to be able to detect and identify various respiratory pathogens, including bacteria, viruses and potential BT agents. Use of molecular based diagnostics potentially facilitates ED physician decision to direct appropriate therapy for the most severe cases, particularly in the instance of a potential BT event.

The primary objective of this study was to evaluate the ability of the Ibis Biosciences/Abbott Molecular T5000/PLEX-ID diagnostic platform to accurately and rapidly detect and identify bacterial, fungal, and viral pathogens associated with respiratory disease, in various complex clinical samples.

Completed Project Overview

The purpose of this project was to assess the potential capability of a novel technology, RT-PCR/ESI-MS, to potentially impact andimprove public health and public health responses by providing rapid and accurate diagnostic information regarding a wide variety ofhuman pathogens including bacteria, fungi and viruses. Multiple evaluations of this technology were performed on various sample types,and again focused on a variety of human pathogens, including Category A-C bacterial pathogens.

All evaluations indicated that use ofRT-PCR/ESI-MS via the PLEX-ID as a diagnostic platform would provide timely sensitive and specific diagnostic information aboutbacterial, viral and fungal human pathogens. Five publications and seven scientific presentations were generated from the workassociated with this project.

Principal Investigator(s) and Researchers(s)

Charlotte Gaydos, Dr.P.H., M.P.H., M.S.

Principal Investigator, PACER