A promising new diagnostic test for detecting drug-resistant tuberculosis (DR-TB) quickly and reliably is finally available, said a new report by Médecins Sans Frontières (MSF).
The possibility that the number of DR-TB cases might treble in South Africa, which has a high TB-burden, highlights the use of this new tool in relation to problems like the pricing and supply of DR-TB medication.
The “GeneXpert” machine – about the size of a milk crate – provides a fully automated nucleic acid amplification test (NAAT) that is effective in the early diagnosis of TB, multidrug-resistant TB (MDR-TB), and TB patients co-infected with HIV, which is more difficult to diagnose.
“I’m so proud to finally have this test,” said Xoliswa Harmans, a former patient with extensively drug-resistant TB (XDR-TB) and HIV, whose diagnosis in 2008 took six weeks. “It was very difficult [waiting for my results]. I was very sick. I couldn’t eat and was losing weight,” said Harmans, who now works as a TB counselor.
Unlike the previous “gold standard” test, which used a culture technique that could take six to eight weeks, this test – endorsed by the World health Organization (WHO) in December 2010 – provides results in about two hours and has a sensitivity rate of 90 percent.
Another advantage of the new test is its simplicity – it can be used by people who are not necessarily health workers because sputum sample “cartridges” are simply inserted into the machine for diagnosis.
The Ubuntu Clinic in Khayelitsha, about 32km from Cape Town, is so far the only South African clinic to use the test. The township has one of the highest national and global rates for HIV and TB. In 2009, antenatal HIV prevalence was 30 percent, and the case notification rate for TB was at least 1,500 per 100,000 people annually – one of the highest levels of TB infection in the world.
“Because of the rise of HIV, TB has become more prevalent,” said Dr Jennifer Hughes, DR-TB co-coordinator for MSF in Khayelitsha. “People with HIV are more susceptible to dying from TB, so if we can diagnose sooner we can get them on treatment sooner.”
Patients diagnosed with DR-TB are immediately eligible for ARV treatment, whereas “normal” TB patients are eligible only if their CD4 count (which measures immune system strength) falls below 350.
Read more of the story here at the IRIN news service:
SOUTH AFRICA: Quick and easy TB diagnosis puts pressure on treatment
Related articles
- Stepping Up Pediatric Tuberculosis Diagnosis in Kenya (netnewspublisher.com)
- More Molecules for Tuberculosis (netnewspublisher.com)
- Caring About Palliative Care in South Africa (netnewspublisher.com)
