Posted on behalf of K. S. Jayaraman.
The Indian government has dismissed reports that a form of incurable tuberculosis has arrived in the country. In a paper published late last year in Clinical Infectious Diseases, Zarir Udwadia and his colleagues at the Hinduja National Hospital and Medical Research Centre in Mumbai reported 12 cases of totally drug-resistant tuberculosis (TDR-TB) (see ‘Totally drug-resistant TB emerges in India’)
But in a statement released on 17 January, the Ministry of Health and Family Welfare dismissed the report. It says that a team of doctors sent by the ministry found that seven of the patients are responding to treatment. “For now, these cases are defined as Extensively Drug Resistant tuberculosis (XDR-TB), and accordingly can be managed by national XDR-TB treatment guidelines,” it says.
The ministry adds that the hospital is not one of the three labs in the country accredited by the government for diagnosing XDR-TB cases — those in which first-line drugs such as isoniazid and rifampicin have failed. “Any type of drug resistant TB can only be diagnosed by laboratory test and not by clinical examination alone,” it says.
“Let them call it what they want,” says Udwadia. “For physician and patient it’s not just a question of semantics — it’s a question of survival and of mortality,” he told Nature. “Look, we are dealing with a disease where there is no effective drug. With XDR at least you have the option of one of the injectables, one of the new quinolones or one or more of the other second-line drugs working. With TDR, as the name suggests, you have very few options.”
Tanjore Balganesh, who until recently headed AstraZeneca’s TB research centre in Bangalore, says the molecular tests to determine whether a strain is XDR or TDR are quite tricky. The reports of TDR-TB cases “raise concern, because the results have come from a really good lab. Even if there is a tendency for the strain to become resistant to second-line drugs, we are in trouble.”
But it is “definitely not time to press the panic button”, he adds. “Whether there is only a tendency, or there is really a resistance, is difficult to say from the data that is available.”