Quantiferon and active TB

Too often amongst the list of pro's and con's of QFT you read the line

It cannot easily distinguish between latent infection and active disease.

However, research has shown that variations in the response to antigens changes between latent and active TB

we have shown for the first time that multiple biomarkers measured in QFT test supernatants have high ability to discriminate between active TB and the absence of active disease

This could be good for researchers but the demands for further lengthy study and assessment and regulatory approval would make such a diagnostic difficult to make available for general use in the foreseeable future.

By employing available diagnostics researchers from Chung-Ang University School of Medicine, Seoul, Korea were successful in diagnosing active TB in false negative polymerase chain reaction (PCR) patients. They found that the combination of high-resolution computed tomography (CT scan) and QuantiFERON Gold was the most effective

the current findings support that the combination of HRCT and QFT-G allow for a rapid diagnosis of PTB in patients who are sputum smear negative or have no sputum production at all.

Note that the study did not use the TB skin test.