Shyam Sunder Bulandi , Section Technical Coordinator , HLA & Molecular Biology, SRL Diagnostics , Gurgaon
"Conventional microbiology will not be replaced in the immediate future, but multiparameter identification of the most important pathogens using array-based detection technologies or rapid real-time PCR-based assays is becoming common in todays laboratories. "
The pace of technological development in clinical molecular diagnostics has been difficult to match for clinicians, payers, and regulators. The explosion of clinical molecular tests in the market place prompted an overhaul in billing codes to provide payers greater transparency into what is being ordered for which patients. Confronted with major healthcare cost drivers in demographic aging and the introduction of medical technologies, payers have subjected molecular diagnostic tests to greater scrutiny – temporarily halting payments or ending coverage for whole groups of tests.
We have seen major changes in clinical virology laboratories over the last decades with the introduction of molecular diagnostic techniques. The future is known – results within 60 minutes for each individual target – however, there are some challenges we will most likely encounter. The equipment needed for blood-borne viruses' assays are combined with US FDA and IVD-approved assays from diagnostic companies. On the other hand, in recent decades diagnostic laboratories have invested an enormous amount of money into a large range of equipment from different companies to enable them to deal with the diverse range of clinical samples and viral targets. Most, if not all of this equipment, was and is for research use only and is thus not FDA or IVD-approved.
Aside from the equipment, there is a wide range of reagents, enzymes, primers, and probes that can be purchased, which have to be combined within the regulatory boundaries, and with the research use only equipment. Therefore, it is obvious that there is, in general, a big difference in assays and equipment used for screening large, mostly negative, and healthy populations, in contrast to the combinations of equipment and reagents needed for the so-called laboratory-developed tests. Moreover, we have also accepted that the equipment used for our laboratory-developed tests are not routinely linked electronically to a laboratory information system (LIS). Another problem is that equipment from different vendors cannot exchange information with each other using a common IT language. Diagnostic laboratories in general are struggling with the lack of connectivity of equipment and some have developed their own solutions. On the other hand, regulatory authorities have not challenged diagnostic companies to solve this lack of connectivity and exchange of information. There is also a tendency to get results faster to ensure that a clinical result, positive or negative, is made available as soon as possible. Again connectivity to a LIS is a necessity, and this issue remains to be solved.
Diagnostics in general is often regarded merely as a cost factor. However, the benefits of diagnostics cannot be denied. A result with a short turnaround time where needed, performed at the highest standards, as we have agreed and as they are maintained by regulatory and accreditation agencies, should be the way to move forward. Looking backwards, we agree that the introduction of molecular tests have changed the clinical virology laboratory tremendously; we can generally detect and quantify all viral targets and we can rapidly develop new assays against new viral treats. The availability of proficiency panels, guidelines, and accreditation processes has improved the overall quality of our work.
The number of diagnostic assays in clinical bacteriology has increased steadily during the last decade. However, conventional microbiology will not be replaced in the immediate future, but multiparameter identification of the most important pathogens using array-based detection technologies or rapid real-time PCR-based assays is becoming common in today's laboratories. The improvement of multiplexing strategies and analysis technologies like MALDI-TOF MS might harbor the potential to cope with the evident problems of modern medicine, especially the steadily increasing threat by multidrug resistant pathogens. Combined with rapidly advancing innovations in microfluidics, the future trend clearly points toward complex multiparametric assays on miniaturized and automated lab-on-a-chip devices, also suitable for point-of-care diagnostics.