Important note: Information in this article was accurate in 2006. The state of the art may have changed since the publication date.
Wall Street Journal - March 24, 2006
Betsy McKay, betsy.mckay@wsj.com
The federal public-health agency also said that the number of people in the U.S. infected with another form of TB -- one that is resistant only to the two most commonly used drugs and is known as multidrug-resistant TB, or MDR-TB -- is rising after generally declining for more than a decade, reflecting the growing global epidemic of drug-resistant TB.
In a survey of 25 tuberculosis laboratories on six continents, the Atlanta agency and the World Health Organization found that 2% of patient samples tested between 2000 and 2004 were resistant not only to the two most commonly used TB drugs, but also to most of the medications that are considered the second line of defense against the disease. This new form of the disease, known as extensively drug-resistant TB, or XDR-TB, is of great concern to public-health officials because it is virtually untreatable with available drugs, leaving patients to "preantibiotic" era methods, such as removal of part of the lung, said Kenneth Castro, assistant surgeon general and director of the CDC's division of tuberculosis elimination.
XDR-TB rose from 5% of MDR-TB cases in 2000 to 6.5% of MDR-TB cases in 2004, and was found most commonly in South Korea, Eastern Europe, and Central Asia, according to the CDC survey. There also have been cases in the U.S.
The new super-resistant TB is spreading at a time when officials are already struggling to bring TB under control. Each year, about nine million people world-wide are diagnosed with new active cases of TB, which is caused by a bacillus spread through the air, mainly by coughing. Two million people die from the disease. TB infects a third of the world's 40 million people with HIV, fueling two epidemics. HIV can activate latent TB infection, and TB speeds progression of HIV to AIDS.
Drug-resistant tuberculosis occurs when patients don't complete a treatment, or when doctors prescribe ineffective drugs, allowing mutant strains of the TB bacteria to multiply. About 400,000 new cases of multidrug-resistant TB emerge globally each year, requiring long and costly treatment, according to the WHO. The CDC said that six new TB drugs will soon be tested in humans, potentially offering an option for treatment of drug-resistant forms of the disease.
The number of people in the U.S. with MDR-TB rose 13.3% in 2004. The vast majority of those in the U.S. with forms of TB that are resistant to drug treatment are foreign-born. Of the 128 people who were diagnosed with MDR-TB in 2004, 97 were from countries such as Mexico, the Philippines and Vietnam, the agency said. MDR-TB made up 1.2% of all U.S. TB cases in 2004 that were tested for susceptibility to drugs, the CDC said.
The CDC also said the decline in TB cases has slowed in the U.S., largely reflecting cuts in funding for TB-control measures, Dr. Castro said.
060324
WJ060301
Copyright © 2006 - The Wall Street Journal. Reproduction of this article (other than one copy for personal reference) must be cleared through the WSJ Permissions Desk.
AEGiS is made possible through unrestricted grants from Boehringer Ingelheim, Bridgestone/Firestone Charitable Trust, Bristol-Myers Squibb Company, Elton John AIDS Foundation, the National Library of Medicine, and donations from users like you. Always watch for outdated information. This article first appeared in 2006. This material is designed to support, not replace, the relationship that exists between you and your doctor.
AEGiS presents published material, reprinted with permission and neither endorses nor opposes any material. All information contained on this website, including information relating to health conditions, products, and treatments, is for informational purposes only. It is often presented in summary or aggregate form. It is not meant to be a substitute for the advice provided by your own physician or other medical professionals. Always discuss treatment options with a doctor who specializes in treating HIV.
Copyright ©1980, 2006. AEGiS. All materials appearing on AEGiS are protected by copyright as a collective work or compilation under U.S. copyright and other laws and are the property of AEGiS, or the party credited as the provider of the content. .