Unworthy replacement: Doctors find it handy to use QuantiFERON-TB Gold latent TB infection kit!
While the government of India banned the use of serodiagnostic antibody-based tests for TB in 2012, the letter from the Treatment Action Group (TAG) and members of the Global TB Community Advisory Board (TB CAB) as well as civil society in India, has pointed towards Qiagen's QuantiFERON-TB Gold, being used to detect active TB disease in the private sector (where serology use was rampant).
"Because of the void created by the serology ban, it appears that private laboratories have essentially replaced the banned serological tests with "TB-Gold" and doctors now think this is a better serological test than the antibody enzyme-linked immunosorbent assays that existed until the ban", says the letter written to Mr Peer M Schatz, chief executive officer and managing director, Qiagen Benelux B.V. on May 14, 2013.
"We urge you and your distributors to market your test as the label indicates and take action to stop the unethical, off-label use of the test for active TB. This is not only relevant for India but also for other high TB burden countries. For instance, we have heard that QuantiFERON-TB Gold is also used in the South African private sector for active TB diagnosis," the letter mentioned.
As per TAG, the Global TB CAB and other representatives of affected communities, they will continue to monitor the situation in India and elsewhere by visiting random labs and talking to distributors and doctors. "We hope that such surveillance confirms that IGRAs are not being promoted for off-label use. We will be obligated to call attention to instances in which this is occurring, and also take up the matter with the the Indian Ministry of Health and Family Welfare and Indian regulatory agency," the letter concluded.
The letter draws its base from a survey titled, 'Perspectives of Quantiferon TB Gold test among Indian practitioners' published in the Journal of Opthalmic Inflammation and Infection in early 2013, that determined the preferences and perspectives regarding the Quantiferon TB Gold test for the diagnosis of tuberculosis (TB) in India. The urvey was distributed among 46 uveitis specialists, rheumatologists, and pulmonologists with a minimum of 2 years experience in the management of tuberculosis, in order to restrict the respondents to specialists who have used this test in their practice in the diagnosis of tuberculosis. Topics included demographics, usage, logistics, effectiveness, and preferences related to the Quantiferon TB Gold test.