There are a couple of new systems just on the market which I suspect will revolutionise PCR testing, particularly where an urgent result is desirable. This is often the case when trying to diagnose Influenza and RSV in the acute care setting.
Cepheid and Roche have both released benchtop PCR systems for Influenza and RSV testing which can be placed in the ward/ED environment, requires minimal training and can give you a highly sensitive result for influenza/RSV in well under an hour.
“Highly sensitive” are the key words here. This is in contrast to rapid antigen tests for Influenza and RSV which although can be useful in certain circumstances, are limited in their clinical usefulness by sub-standard sensitivity. RSV and Influenza rapid antigen tests are now living on borrowed time….
The other highlight is “under an hour”. This allows real-time management of the patient in the ED./acute assessment ward (including treatment, isolation, cohorting, discharge etc.) based on the result of the PCR test.
The big downsides of course are the cost and the “one at a time access”. More expensive (the cost will come down)than traditional batched PCRs it might be a while before such testing systems become commonplace. (A lot depends on the funding model of your healthcare system.)
But they will, you can be sure of that.
I have had to do some work on Ebola Preparedness recently and this has involved looking at the role in such cases of various point of care tests (POCT), that can thus be utilised at the patient’s bedside.
At first sight, the POCTs I have looked at seem fantastic. They generally produce accurate results, they are very quick and even I can use them.
However there is a darker side..
There are aspects of POCT where the lab still wins hands down. This is with regards to electronic recording and interfacing of results into a result repository, external and internal quality control of the test, maintenance of the equipment, and training the users.
With regards to the first problem I think wireless interfacing of POCTs will start to become more prevalent as the technology is now available (click here for an example).
With regards to the other problems, I think it is extremely important that the laboratory has complete jurisdiction over POCT within any given institution, and that the accreditation agencies recognise these pieces of equipment as part of the laboratory. It is only by doing this that all the quality control measures that are necessary for such equipment can be implemented and assessed.
I don’t see POCT as a threat to the laboratory, just because the equipment is not physically in the laboratory itself. A good laboratory should embrace POCT and see it as an integral part of their operation.
Click here for another article on the development of POCT and Quality Control issues (about a 10 min read)