Rapid TB test more effective than traditional diagnostics for detecting cases among children

17 July 2011 - London - Xpert MTB/RIF, a rapid automated test for tuberculosis (TB) has proved more effective than smear microscopy for diagnosing cases of TB in children, according to a study published in The Lancet.

The World Health Organization has already recommended the test for diagnosing active TB in adults. However no data had previously existed on its use with children. TB is difficult to diagnose in children, even when laboratory facilities are good.

The study enrolled 452 children of 15 years or younger with suspected pulmonary TB from pediatric wards in Cape Town, South Africa. Using induced sputum samples, doctors managed to detect twice as many cases of active TB using the Xpert MTB/test compared to using traditional smear microscopy.

"The MTB/RIF test is widely anticipated to replace smear microscopy in resource-poor settings where HIV co-infection or drug-resistant tuberculosis are common, and our results suggest that its use is a major improvement over use of smear microscopy," said Dr Mark Nicol, one of the authors.

The Xpert MTB/RIF test utilizes nucleic acid amplification to detect both TB and sensitivity to rifampin, one of the first-line drugs to treat tuberculosis. The table-top device can detect TB and resistance to rifampin within 100 minutes, compared to up to three months with traditional diagnostics.