November 6, 2008
Half Of Patients With Extensively Drug-resistant TB Die
New research on drug-resistant tuberculosis found that the hard-to-treat disease results in death for half of patients who get it.
South Korean researchers presented the study "“ one of few to track survival rates from the condition called extensively drug-resistant TB "“ in the latest edition of the American Journal of Respiratory and Critical Care Medicine.
The study consisted of 1,407 patients who had either multidrug resistant TB, which is the most aggressive because it resists at least one of the two main TB drugs, or extensively drug-resistant TB, or XDR-TB, which defies nearly all drugs used to treat TB.
Of those with extensively drug-resistant TB (XDR-TB), 49 percent died compared to 19 percent of those with multidrug resistant TB (MDR-TB), according to lead author Dr. Tae Sun Shim of Asan Medical Center in Seoul.
The patients were diagnosed between 2000 and 2002 and were followed for up to seven years, the researchers said. About 5 percent of the patients had XDR-TB.
"We have so little information on XDR-TB to begin with," said D'Arcy Richardson of the Seattle-based nonprofit group PATH. Richardson wrote a commentary with two other TB experts accompanying the study,
Cases of drug-resistant tuberculosis account for about 5 percent of the 9 million new TB cases annually, the WHO said. It said that 489,139 MDR-TB cases emerged in 2006, and about 40,000 were XDR-TB.
"We know that it's a very big problem in Eastern Europe. We know it's a very big problem in Asia, particularly in India and China, where they don't necessarily have large percentages of MDR and XDR but because of the size of the population with TB we have significant numbers," Richardson said.
TB killed 1.7 million people worldwide in 2006, the WHO said. It can be spread by breathing in air droplets from a cough or sneeze of an infected person.
WHO is working to dramatically reduce the burden of TB, and halve TB deaths and prevalence by 2015, through its Stop TB Strategy and supporting the Global Plan to Stop TB.
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