Point-of-care molecular diagnostic system: A novel way to identify pathogens in the clinical setting

 
By: Mirrah Almira - CMI Fellow  

Introduction: Eager to solve one of the biggest problems in the clinical setting, engineers and physicians at the University of Pittsburgh have teamed up to create a rapid, reliable, and inexpensive system that is able to detect and identify the pathogens causing hospital-acquired infections.

[Pittsburgh, February 11, 2015] According to an article published in 2013 by Center of Disease Control and Prevention (CDC), drug-resistant microorganisms infect 2 million of people and kill 23,000 patients annually. Most of these cases are hospital-acquired infections (HAI) caused by either of these two drug resistant organisms: methicillin-resistant Staphylococcus aureus (MRSA), or a member of carbapenem-resistance Enterobacteriaceae (CRE) family like carbapenemase-producing Klebsiella pneumoniae. Broad spectrum antibiotics will not be effective to treat infections caused by either of these two microorganisms.

Therefore, for each infection case, confirming the identity of the microorganism is a very important process. Correct identification of the microorganism will allow physicians to effectively and efficiently treat the infection, enabling them to administer the proper antibiotic in a timely fashion.

Currently, clinical diagnosis of the pathogen (microorganism that causes infection) relies on resource-extensive and time consuming microbiology laboratory routines that can take 3-4 days to finish. In the mean time, the critically ill patient remains in the ICU and may receive inappropriate antibiotics.

Other methods are nucleic acid amplification testing (NAAT) and isothermal NAAT (INAAT) which detect the genetic material (nucleic acid) of the bacteria causing the infection. Although NAAT and INAAT offer greater sensitivity compared to biological assays such as immunoabsorbent, hybridization, and in vitro culture tests, these two methods have not successfully addressed the issue of near-patient point-of-care (POC) applications.

Realizing that identification of specific pathogens is critical, a team led by Dr. Abhay Vats from the University of Pittsburgh has developed a rapid, inexpensive, palmtop computer-based point-of-care (POC) device, which they called the "box", and rapid test method for detecting MRSA and carbapenemase-producing K. Pneumoniae. The assay itself employs a new isothermal NAAT method, called Spiral Isothermal DNA Replication (SPIDR), which was invented Dr Vats. It utilizes simple heaters and real time detection of fluorescence. The device is currently in the prototyping phase. It is a small-footprint, optoelectronic analyzer equipped with a wireless transmitter able to send the recorded data to a palmtop computer, like iPad and iPhone, for analysis and display. The combination of the device and the rapid assay will answer the need for a sensitive and accurate test system that is easy to use and can determine the pathogen identity rapidly so that the appropriate antibiotic treatment can be administered quickly.

The team behind this system consists of innovative physicians and engineers. They are:

 

 
The $18,000 grant from CMI in 2014 is an extension of an initial award of $25,000 in 2013. On the technical side, the team has been able to install a new heater component for the SPIDR assay, miniaturize the box, and optimize the SPIDR assay for detecting genes that are responsible for antibiotic-resistance.

On the business side, the team has developed a market plan, filed their patent for this technology (published by United States Patent and Trademark Office in December 2014), and initiated a relationship with company that is interested in licensing the technology.

In the future, the team plans to focus on the technical development of the "box" and also further validation of the assays. The team also plans to take the research-use-only (RUO) pathway as the initial marketing route for the assays and the box. This RUO way can be either through a startup company or a Clinical Laboratory Improvements Amendment (CLIA) certified lab in Pittsburgh. (MA)