Asian Scientist (11.19.12)
Researchers from the Beth Israel Deaconess Medical Center in Boston, Mass., have developed a paper-based test for drug-induced liver toxicity. Liver tests are important for patients being treated for TB as the anti-tuberculosis drugs rifampicin and pyrazinamide can cause liver damage, especially in people co-infected with hepatitis B or hepatitis C. Also, people with HIV can develop liver damage when treated with nevirapine-based drugs. US doctors normally check blood to determine if patients are developing serious liver damage and adjust medications to suit, but in developing countries, clinicians may not have easy access to laboratory facilities to test for drug-induced liver injury, particularly clinicians in rural areas.
The new test uses a postage stamp-sized paper device with channels and wells that mix, split, and filter blood from a finger prick to detect chemical markers. In the trial, researchers used existing blood samples to compare the device to established tests. The overall accuracy of the new test was 90 percent compared with the gold standard of 100 percent. In 15 minutes, the test indicated normal, moderate, or high levels of liver markers based on color changes. It also includes a control that confirms the test was accurate. The estimated cost of the test is 10 US cents.
According to Jason Rolland, senior director of research at Diagnostics For All, which developed the technology, the test is cheap, easy to use, and portable, without need of electricity or instruments. Nira Pollock, assistant professor of medicine at Harvard Medical School, coordinated the trial and is liaising with the National Hospital for Tropical Disease in Vietnam to conduct field trials with HIV patients. If the test works as well in the field trials, the researchers are hoping to have a commercial product by 2014. At present, Diagnostics For All can manufacture 500 to 1,000 tests per day.
The study, “A Paper-Based Multiplexed Transaminase Test for Low-Cost, Point-of-Care Liver Function Testing,” was published in the journal Science Translational Medicine 2012 (Sep 19;4(152):152ra129).