On April 9, 2012 we posted a blog entitled Combining TBDx with Other Detection Technologies. The blog illustrated how TBDx™ could be used, in a layered diagnostic protocol, to identify the most highly probable TB suspects for additional confirmation and evaluation for drug resistance, using GeneXpert or a similar molecular test. This past weekend in Kuala Lumpur, during the 43rd Union World Conference on Lung Health, this concept was on further display.
Dr. David Clark, the Deputy CEO of the Aurum Institute, and closely aligned to our development of TBDx™ and evaluation of GeneXpert in South Africa, provided a model illustrating the cost benefits of combining these technologies. Entitled Automated TB Microscopy – Recent results and a model to increase pre-test probability to gene-based diagnostics, Dr. Clark presented the results of recent performance testing using multiple TBDx™ detection algorithms, and described the potential of TBDx™ to reduce laboratory costs by directing the most highly probable TB cases to more expensive molecular tests, such as Xpert.
Presentation Key Points:
- TBDx™ performs significantly better than conventional microscopy.
- All TBDx™ algorithms, when combined with Xpert, perform better than conventional microscopy and Xpert, at 50% to 80% of the cost.
- The sequential use of TBDx™ and Xpert perform similarly to Xpert alone, but at 45% of the cost.
As Dr. Clark determines in his presentation, it is feasible to conclude that computer vision and automated TB microscopy can replace conventional microscopy and that it can increase the pre-test probability of TB detection and reduce the cost of molecular testing when used in sequential combination, thus making it more affordable for healthcare providers.
Further performance and testing analysis combining these two technologies will start soon at the Center for Tuberculosis in Johannesburg, South Africa.