The Union ministry of health has denied the presence of totally drug resistant tuberculosis (TDR-TB) reported in Mumbai. Researchers at the Hinduja Hospital in Mumbai documented the presence of this strain of TB in India for the first time in the December 21, 2011 edition of the journal, Clinical Infectious Diseases. Patients suffering from it are resistant to all available drugs to cure the deadly disease.
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Since October 2011, Mumbai has reported 14 instances of patients carrying the TDR-TB strain; of them, four patients have died, including a 13-year-old boy. Twelve cases are from the Hinduja hospital in Mahim and the remaining two are from Jamshedji Jijibhoy Hospital in Byculla.
But the health ministry in its press release on January 17 said that the term TDR-TB is “non-standardized” and “misleading”. It added that the term is neither recognised by the World Health Organisation (WHO) nor by the government-run national programme for TB control—Revised National TB Control Programme (RNTCP).
TDR TB does exist, say experts
However, doctors and public health experts say the term used to classify the 14 Mumbai patients is not new and has been used earlier in other countries.
“Cases of TDR-TB do exist. There is nothing extra-ordinary that these cases have come up. Many patients do not complete the treatment under RNTCP or the drugs they may be taking are not appropriate. Resistance to drugs develops in such cases. TDR-TB cases in India are expected. But the government is always in a denial mode,” says Sarman Singh, head of clinical microbiology department in the All India Institute of Medical Sciences (AIIMS).
TDR-TB cases are similar to extensively drug-resistant TB (XDR-TB), in which resistance develops to the second-line drugs for TB as well, says Soumya Swaminathan, scientist with the department of clinical research at the Tuberculosis Research Centre in Chennai, Tamil Nadu. “TDR-TB is very similar to the XDR-TB. It is very difficult to treat these cases,” she says.
Mortality in cases resistant to second-line drugs is more than 80 per cent and the only options left to treat these patients are either surgery or by giving patients drugs that have not been tried before.
The first-line drugs for TB are isoniazid, rifampicin, ethambutol, pyrazinamide and streptomycin. Once patients develop resistance to these drugs, they are given second-line of drugs—ofloxacin, moxifloxacin, kanamycin, amikacin, capreomycin, para-aminosalicylic acid and ethionamide.
Lab tests contested
The ministry has also contested the laboratory tests carried out by the doctors at Hinduja Hospital.
“The Hinduja Hospital Laboratory is not accredited by the RNTCP for culture and sensitivity for second line drugs to diagnose XDR-TB or TDR-TB cases, and is only accredited for conducting Drug Susceptibility Testing (DST) by liquid culture and sensitivity for first line drugs,” the release says.
The authors of the study, Zarir Udwadia, Camilla Rodrigues, Rohit Amale and Kanchan Ajbani, performed DST through bacteria culture at different concentrations of the antibiotic and found that the patients were resistant to all the WHO prescribed first and second line of drugs for treating TB. In addition, three of the patients underwent genotypic DST analysis using more advanced tests. They added in the study that the laboratory at the hospital is a referral laboratory and a RNTCP-accredited laboratory for Mumbai.
Besides DST, they also audited the prescriptions of the patients that revealed that three patients had received “erratic, unsupervised second-line drugs, added individually and often in incorrect doses, from multiple private practitioners (average of four physicians during a 18-month period) in an attempt to cure their multi-drug resistant TB (MDR-TB).”
The Maharashtra health department joint director for TB control, P Y Gaikwad, said the state government is planning to conduct field visits to assess how widespread the problem is in the state. “The state health department will be sending teams to the field and identifying more such cases, including cases in TB hospital in Sewri, Mumbai. Samples collected may even be sent to National TB Institute at Bengaluru. Samples collected will be those that are resistant to second-line TB drugs,” he said.
Most docs can't prescribe correctly
India has become the third country in the world to identify patients with TDR-TB. Earlier, TDR-TB cases were first identified in two patients in Italy in 2007 and then in 15 patients in Iran in 2009.
The authors write, “Only 5 of 106 private practitioners practising in a crowded area called Dharavi could prescribe a correct prescription for a hypothetical patient with MDR tuberculosis. The majority of prescriptions were inappropriate and would only have served to further amplify resistance, converting MDR tuberculosis to XDR tuberculosis and TDR tuberculosis. We would urge that patients with MDR tuberculosis only be treated within the confines of government sanctioned DOTS-Plus programmes to prevent the emergence and spread of this untreatable form of tuberculosis.”
As per the 2007 WHO global resistance report, only one per cent of patients in India with multi-drug resistance tuberculosis have to the Directly Observed Treatment, Short-course (DOTS)–Plus initiatives, treatment regime prescribed under RNTCP. India accounts for 20 per cent of the world’s MDR tuberculosis load.