The number of labs/private hospitals in the country offering the WHO-approved tests like GeneXpert, Line Probe Assay (LPA) for diagnosing TB disease at a subsidised price has reached 54. There are over 10,000 collection centres spread across the country.
In eight months since the novel initiative — Improving Access to Affordable & Quality TB Tests (IPAQT) — was launched, the number people accessing these labs for the subsidised tests has risen to 30,000. Of them, over 15,000 people have availed the Xpert test. These people have been referred by private doctors.
That the WHO’s Global Tuberculosis Report 2013 had highlighted this novel initiative reveals how important it is.
Four labs offer this test in Chennai — YRG Care, Hitech Diagnostic Center, Bharat Scans & Specialties Lab and SRM Institute for Medical Science. Unlike these four labs, the TB control programme in Tamil Nadu (RNTCP) provides this test free of cost at the Intermediate Reference Lab (IRL), Chetpet, Chennai.
The ipaqt.org site provides the details of other labs in the country that offer the WHO-approved subsidised tests.
But starting January 15, 2014, the cost of the subsidised Xpert test will go up from Rs.1,700 to Rs.2,000. According to a reliable source from one of the non-profit partners of the initiative, the compulsion to increase the price was due to the depreciation of rupee against the U.S. dollar.
The agreement with the manufacturers of Xpert was reached when the dollar exchange rate was Rs.53. The agreement allowed for a 10 per cent variation in the exchange rate.
According to the source, despite the 10 per cent variation in place, the cost of the test was not increased even when the rupee depreciated 19 per cent.
“The price is internationally set at $9.98 per cartridge. No matter who is buying it (in any country), if their currency is weaker against the U.S. dollar, then it will affect them,” Dr. Madhuka Pai noted in an email to this Correspondent. Dr. Pai is one of the Governing Council Members of IPAQT and an Associate Professor at McGill University, Canada.
Despite the increase, the cost differential between the subsidised test offered by the 54 labs/hospitals and those offered by labs which are not part of the IPAQT initiative is substantial.
Labs which are not part of the IPAQT initiative charge anywhere between Rs.3,500 and Rs.5,000 for the Xpert test.
“Before IPAQT was launched, the price of Xpert MTB/RIF in the private sector was in excess of Rs.3,000, and less than 500 tests were done in the private sector in all of India. After IPAQT was launched 15,000 Xpert tests have been done. This suggests that making WHO-endorsed tests more affordable can increase uptake,” he noted. “But much more can be done, given the heavy TB burden in India and the large private sector.
“There is not enough awareness among private doctors about IPAQT and the fact that good, WHO-endorsed tests are now available at these lower prices. Member labs are just starting to take up demand generation and awareness initiatives.”
The increase in the cost notwithstanding, there are abundant reasons for opting for the GeneXpert test. While the sensitivity of smear microscopy is about 50 per cent, Xpert has 90 per cent sensitivity (in smear positive cases) and 98 per cent specificity. It can therefore diagnose more people who have TB and with a greater degree of confidence. It can turn in results in about two hours.
And unlike smear microscopy, Xpert can also indicate resistance to rifampicin — a first-line TB drug. Almost 98 per cent of people who are resistant to rifampicin are also resistant to isoniazid, another first-line TB drug.
A person is said to have multi-drug resistant TB when he is resistant to at least two first-line TB drugs. In short, Xpert can help doctors know if a patient suffers from MDR-TB even before starting treatment.
While the Revised National TB Control Programme (RNTCP) uses Xpert and other WHO-approved diagnostic tests like LPA only for retreatment cases (where the patient had earlier been successfully treated for TB), private practitioners prefer Xpert even in the case of fresh cases (those who have never before been down with TB disease).
A ban on the serological test, one of the major decisions taken in early 2012 by the government of India, will go a long way in correctly diagnosing TB disease on time.
The serological TB test diagnoses TB disease based on the presence of antibody response. But it’s a fact that the presence or absence of antibody response does not reflect the true TB disease status. Hence, serological test is a highly unreliable for diagnosing TB disease.
But the ban had created a void in the diagnostic tests that the private labs could offer. The IPAQT initiative is now successfully filling this vacuum.
“The idea is to promote the high volume but low margin model that aims to make products more affordable to the bottom of the pyramid,” Dr. Pai explained. “Surveys conducted with practising doctors in the private sector indicate that unequal financial gain is only one of the reasons for prescribing inappropriate tests.
“The other reasons include lower availability (and higher costs) of high-quality, WHO-endorsed tests [till IPAQT came into the picture], and lack of awareness about the value of these tests.”
Not for TB disease
Unfortunately, with the serological test banned, many labs are offering TB Gold blood test. “The Indian private sector, for many years, has been heavily reliant on inaccurate serological blood tests. [As a result], when the ban happened in 2012, the market may have shifted towards TB Gold because this test also uses blood,” Dr. Pai noted.
It is important to note that the TB Gold test can only diagnose latent TB (TB infection) and cannot and should not be used for diagnosing TB disease.
With nearly 40 per cent of the adult population in India infected with TB bacilli, the blood test is of no use except in instances where there is scope for preventive therapy — child contacts of TB cases, individuals with HIV-infection and other immune-compromising diseases.