Quantiferon-TB

Hi, if i've not mistaken, this is a very expensive test as compared to the common mantoux test. I've heard its still on trial in some hospital.

It is available at many reference labs, but it is expensive & has some limitations in terms of requiring a sample to be delivered to the lab within 12 hours. It is being marketed as a more accurate, and certainly much more objective test than a PPD. I am my hospital's Infection Control/Employee Health Nurse, and we currently, as a low risk facility, cannot justify switching to Quantiferon.

Thank you so much for your responses. I understand the test is expensive but compared to the expense (financial and physical) of undergoing 9 months of medication treatment with potential side effects; I would think it's worth it.

It is becoming more available in the US and indeed in other countries. eg Japan have recently abandened their PPD testing resorting to annual X rays to test their various populations until quantiferon TB Gold was approved last year and is now being recommended in their updated guidelines. In the US, Sanfrancisco were the first city to completely switch to the first version of quantiferon and more recently to the Quantiferon TB Gold for certain populations such as the homeless. They are now extending their testing to a wider population as logistics expand in the laboratory.

A newer version, quantiferon TB Gold Intube, is currently being evaluated and under FDA approval which removes the 12 hour limit of getting blood samples to the LAB. This version has special tubes to collect the blood sample and the antigens begin reacting immediately, thus making the test more sensitive. The USAF are currently evaluating this version. They are looking at replacing their PPD testing of soldiers with the quantiferon test. So over the coming years you will find this test being used more often in situations where the PPD has its problems of false negatives and false positives.

It is certainly worthwhile having a quantiferon test if available in your area prior to beginning a regime of TB treatment to confirm the PPD diagnosis. This is where the big savings are being experienced as resources are not being wasted treating people wrongly diagnosed as having TB.

I believe the test is offered in a growing number of labs and hostipals around the country. Some that I know of are

San Francisco Dept Health Labs

Nabraska University medical Centre (www.nphl.org/documents/TBInterferon2.pdf)

Texas Department of State Health Services (www.dshs.state.tx.us/lab/refman.pdf)

There are at least 40 major health departments, universities and labs offering the quantiferon TB test as a service. Over the coming years it will become available in all states and counties in the same manner as other blood tests. Check with your local health department for more information.