News / Africa

Tough TB Responds to Drug Treatment

A young patient with potentially fatal MDR TB in isolation in a hospital in South Africa (Photo: D.Taylor)
A young patient with potentially fatal MDR TB in isolation in a hospital in South Africa (Photo: D.Taylor)

Multimedia

Audio
Joe DeCapua
An antibiotic used to treat severe infections shows promise against a very resistant and deadly form of tuberculosis. XDR-TB is resistant to at least four of the drugs used most often against the disease.


Extensively drug resistant tuberculosis – or XDR-TB – is still considered rare, although cases have been reported in nearly 80 countries. Health officials believe the number of XDR-TB cases is underreported because there’s no specific test for it.

It can be cured, but the odds against that happening are often quite high. It can kill quickly, especially if a person is co-infected with HIV, the virus that causes AIDS.

Dr. Ray Chen, a staff clinician at the National Institute of Allergy and Infectious Diseases, says XDR-TB is the next step after MDR-TB, or multi-drug resistant tuberculosis, which is a lot more common.

“That’s been a known problem for many years, primarily as a result of people who don’t take their drugs well. And then the tuberculosis bug slowly develops resistance to the drugs that are used,” he said.

MDR-TB is resistant to two of the top line drugs used for standard tuberculosis therapy. When the disease becomes resistant to two additional first-line drugs, it’s upgraded to XDR-TB.

“It came to world attention in 2006 in a study in South Africa where a number of patients were found to have this extensive resistance to tuberculosis drugs, and they had a very high mortality rate. And so it became recognized as a major problem for tuberculosis,” he said.

In fact, the mortality rate was as high at 90 percent in patients also infected with HIV.

Standard TB treatment can take up to six months. MDR-TB treatment can last between 18 and 24 months.

So researchers knew that more drugs were needed to tackle the various forms of TB.  They had heard of some informal studies using the drug linezolid on TB patients with some success. But there was no formal study.

Linezolid is a drug that’s already on the market and it’s approved for the use of resistant bacteria, which we call gram-positive bacteria that don’t respond to typical antibiotics.

To find out, researchers tested linezolid on 41 patients with XDR-TB. The patients already had been treated for six months with the best TB drugs available, but failed to respond. Chen said linezolid was added to their regimen.

“We found that adding the linezolid had a significant effect and that most of the patients converted their sputum from showing tuberculosis to not having tuberculosis in the sputum by six months. About 87 percent of the patients became negative for tuberculosis within six months. So it showed a very good response,” he said.

That’s the good news. The bad news is many of the patients suffered severe side effects. These include nerve problems with hands and feet going numb. There were also eye problems and abnormalities with red and white blood cells. Use of the drug was stopped before any of the patients suffered permanent damage.

As a result, Chen said more studies are needed to determine whether it can safely be used on a large-scale in combination with other drugs. He also says new, potent antibiotics will be coming on the market and these may be tested on TB, as well.

You May Like

EU Court Fines Poland for Hosting CIA 'Black Sites'

Ruling is first time a court has acknowledged suspects were held and tortured at the sites, under US program launched following the 9/11 terrorist attacks More

Migrant Issues Close to Home Spur Groups to Take Action

Groups placing water, food in the desert, or aiding detainees after release, have one common goal: no more deaths of migrants crossing illegally into the US More

Video At AIDS Conference, Prevention Pill Stirs Excitement

Truveda shows promise, spurring debate over access and other approaches More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Israel Targets Gaza Supply Tunnelsi
X
July 24, 2014 4:42 AM
The Israeli military has launched a ground operation in Gaza to destroy the myriad tunnels that may have been used to smuggle weapons to Hamas. VOA's Zlatica Hoke reports that could mean more hardship for the people of Gaza, who obtain some of their essential supplies through these underground passages
Video

Video Israel Targets Gaza Supply Tunnels

The Israeli military has launched a ground operation in Gaza to destroy the myriad tunnels that may have been used to smuggle weapons to Hamas. VOA's Zlatica Hoke reports that could mean more hardship for the people of Gaza, who obtain some of their essential supplies through these underground passages
Video

Video MH17's 'Black Boxes' Could Reveal Crash Details

The government of Malaysia now has custody of the cockpit voice and flight data recorders from Malaysia Airlines Flight 17, which was hit by a missile over Ukraine before crashing last week. As VOA's Carolyn Presutti reports, the so-called black boxes may hold information about the final minutes of the flight.
Video

Video Living in the Shadows Panel Discussion

Following a screening of the new VOA documentary, "AIDS - Living in the Shadows," at the World AIDS conference in Melbourne, a panel discussed the film and how to combat the stigma associated with HIV/AIDS.
Video

Video IAEA: Iran Turns its Enriched Uranium Into Less Harmful Form

Iran has converted its stockpiles of enriched uranium into a less dangerous form that is more difficult to use for nuclear weapons, according to the United Nations’ Atomic Energy Agency. The move complies with an interim deal reached with Western powers on Iran's nuclear program last year, in exchange for easing of sanctions. Henry Ridgwell reports for VOA from London.
Video

Video Relic of Saint Draws Catholics Worried About Immigration Issue

A Roman Catholic saint who is a figure of devotion for those crossing the border into the United States is attracting believers concerned about the plight of undocumented immigrants. Mike O'Sullivan reports from Los Angeles, where a relic of Saint Toribio has drawn thousands to local churches.
Video

Video US Awards Medal of Honor for Heroics in Bloodiest of Afghan Battles

U.S. combat troops are withdrawing from Afghanistan, on pace to leave the country by the end of this year. But on Monday, U.S. President Barack Obama took time to honor a soldier whose actions while under fire in Afghanistan earned him the Medal of Honor. VOA's Jeff Seldin has more from the Pentagon.
Video

Video Ukraine Rebels Surrender MH17 Black Boxes

After days of negotiations, a senior separatist leader handed over two black boxes from an airliner downed over eastern Ukraine to Malaysian experts early Tuesday. While on Monday, the U.N. Security Council unanimously demanded that armed groups controlling the crash site allow safe and unrestricted access to the wreckage.
Video

Video In Cambodia, HIV Diagnosis Brings Deadly Shame

Although HIV/AIDS is now a treatable condition, a positive diagnosis is still a life altering experience. In Cambodia, people living with HIV are often disowned by friends, family and the community. This humiliation can be unbearable. We bring you one Cambodian woman’s struggle to overcome a life tragedy and her own HIV positive diagnosis.

AppleAndroid