Sunday, January 29, 2012

                                                     Totally Drug Resistant TB in India 
TB is already one of the world’s worst killers, up there with malaria and HIV/AIDS, accounting for 9.4 million cases and 1.7 million deaths in 2009, according to the WHO. At the best of times, TB treatment is difficult, requiring at least 6 months of pill combinations that have unpleasant side effects and must be taken long after the patient begins to feel well.
Tuberculosis is a bacterial disease, treated with antibiotics. As has been documented in other places, over time many kinds of bacteria develop resistance to antibiotics. TB bacteria have been especially adept at this. We’ve already seen multi-drug resistant TB, and extensively drug resistant TB. Totally drug resistant tuberculosis was the logical progression, and we’ve reached it.
At least 12 patients were reported infected with TB that has become resistant to all the drugs used against the disease, tech site said. The discovery makes India the third country in which a completely drug-resistant form of the disease has emerged, following cases documented in Italy in 2007and Iran in 2009.  Because of the mismatch between treatment and symptoms, people often don’t take their full course of drugs — and from that (and some other factors I’ll talk about in a minute) we get multi-drug resistant and extensively drug-resistant, MDR and XDR, TB. MDR is resistant to the first-choice drugs, requiring that patients instead be treated with a larger cocktail of “second-line” agents, which are less effective, have more side effects, and take much longer to effect a cure, sometimes 2 years or more. XDR is resistant to the three first-line drugs and several of the nine or so drugs usually recognized as being second choice.
As of last spring, according to the WHO, there were about 440,000 cases of MDR-TB per year, accounting for 150,000 deaths, and 25,000 cases of XDR. At the time, the WHO predicted there would be 2 million MDR or XDR cases in the word by 2012. 
This awful news leaves us with a lot of what-do-we-do-next questions. How do we handle the people who have TDR TB? How do we keep it from spreading? Is this a sign we’re taking the wrong approach to fighting the disease? Here’s hoping we can find some kind of answers.
Since the 1960s, two drugs — isoniazid and rifampicin — have been the standard TB treatment. Although episodes of resistance cropped up periodically, during the 1990s the incidence of multiple drug resistance grew significantly, leading researchers in 2006 to refer to it as extensively drug-resistant tuberculosis (XDR-TB). Surveillance data from the WHO indicate that XDR-TB is present in at least in 58 countries, with an estimated 25,000 cases occurring each year.
Epidemiologist Carole Mitnick of Harvard Medical School in Boston, Massachusetts, agrees that TDR-TB is not new, and points to the history of XDR-TB. “When XDR-TB was first named, it was a phenomenon that had existed but hadn’t gotten much attention before. TB in general doesn’t receive a lot of attention,” she says.
As the full form of TDR-TB suggests, none of the known TB combination drugs work on the patient. All 12 showed resistance to 12 drugs. "The TB bacilli have obviously mutated. The emergence of TDR-TB has grave implications for public health," said Hinduja Hospital's Dr Zarir Udwadia, whose observations have been published in the latest issue of the US-based Clinical Infectious Diseases (CID) peer review journal. His team started isolating TDR-TB cases among patients with pulmonary TB in October 2011.
Dr Amita Athawale, who heads KEM Hospital's chest department, said TDR-TB was a reality in India. "The cases we clinically isolate are just the tip of the iceberg," she said. TB is one of the biggest killers in India, along with heart attack.
Controversy over TDR TB
Mumbai continues to paint a gory picture of extremely resistant tuberculosis (XDR-TB) TB with Bai Jerbai (BJ) Wadia hospital alone having identified at least 11 children infected with XDR-TB after testing 500 children infected with TB in the last three years.Amid the current controversy over TDR-TB, a term which is being rejected by state and government health agencies, Dr Shah told DNA, “We have diagnosed 11 patients with ‘partial XDR-TB’ which shows that the bacteria is mutating fast due to poor and partial treatment.”Dr PY Gaikwad, joint director, health (TB) at the state health department, said, “There is no term like partial XDR-TB. To say XDR, patient needs to have resistance to fluoroquinoline and aminoglycoside both. However, we need to know the details of such patients and also whether the testing lab is accredited. Otherwise, one cannot confirm that the patient has XDR-TB.” He further added that doctors must try to get details of the two missing children with XDR-TB so that the state and BMC can provide help.