TB type is lethal for HIV patients
A highly drug-resistant form of tuberculosis has killed about 85% of South African HIV patients who have become infected, presenting one of the most worrisome problems in HIV and tuberculosis control, researchers reported Sunday.
About 330 cases of so-called extensively drug-resistant, or XDR, tuberculosis have been verified in South Africa over the last year, said Karin Weyer of the South African Medical Research Council in Pretoria.
The outbreak began in KwaZulu-Natal province last year and is now found throughout the country, she said.
Dr. Paul Nunn, coordinator of tuberculosis and HIV at the World Health Organization, called the 85% mortality rate “completely egregious.”
The South African findings were presented at the opening of the Conference on Retroviruses and Opportunistic Infections in Los Angeles. It is the largest scientific gathering for AIDS researchers.
XDR tuberculosis is resistant to most drugs but can be treated with four antibiotics if caught early enough.
“This creates a huge challenge in terms of infection control, especially in settings where high numbers of HIV-positive individuals are converging,” such as hospitals, Weyer said.
Doctors have seen sporadic cases of XDR tuberculosis for decades, but it gained attention after the outbreak in KwaZulu-Natal province.
The WHO has reported that the number of countries with XDR tuberculosis has increased from 17 in March to 28 today.
The hardest-hit areas include South Africa, South Korea and parts of Eastern Europe, according to the U.S. Centers for Disease Control and Prevention.
The disease can kill quickly, particularly among HIV patients, whose immune systems are weakened.
Researchers reported last year that median survival time for patients was 25 days after their diagnosis.
Weyer said the disease appeared in about 10% of patients who had been diagnosed with multi-drug-resistant TB, a less severe form.
XDR tuberculosis has appeared in the U.S., but at much lower levels -- 47 cases since 1993, resulting in 13 deaths, said Dr. Kevin Fenton, director of the CDC’s National Center for HIV, STD and TB Prevention.
The death rate is six times higher than the rate for typical tuberculosis, he said.
Resistance testing is widespread in the U.S., but Fenton said the South African cases were a “wake-up call” for strengthening TB surveillance and prevention.
He noted that there were large numbers of multi-drugresistant TB cases in China, Russia and India, providing more opportunities for the development of XDR tuberculosis.
“We increasingly live in a small world,” he said. “With foreign travel and migration to the U.S., we have to be very much aware of emerging threats of XDR TB.”