November 20, 2015
Researchers at the University of California (UC) Irvine Health have developed a cost-effective test that can detect and confirm the presence of hepatitis C virus (HCV) infections in one go.
Presenting the findings at the Annual Meeting of American Association for the Study of Liver Disease (AASLD) in San Francisco, Dr Ke-Qin Hu, director of hepatology services said the new method would significantly improve sensitivity and specificity, compared to current tests.
Dr Hu explained that, for the first time, urine samples could be used to both screen and diagnose the virus, which is spread through bloodborne pathogens.
The cost-effective test could make it simpler for healthcare workers to see whether they have been exposed to hepatitis C after a needlestick or other medical sharp injury.
Currently, a blood test is needed to confirm that a person is infected with the virus. This is expensive as it requires two steps to get a firm diagnosis, which also means it can be inconvenient for patients and is not suitable in many places around the world.
According to the team, many developing countries are not equipped to perform the two-step test, especially the latter HCV-specific part.
Firstly, virus-specific antibodies must be detected in the blood and then the sensitive HCV RNA PCR test must be performed to see whether the infection is active. Although this blood-based method is specific and sensitive, it is itself to determine whether an infection is old or has been previously treated.
Dr Hu, professor of gastroenterology and hepatology at UC Irvine School of Medicine, said: "Finding a more convenient, easy-to-use and cost-effective screening alternative is imperative, because HCV is significantly under-screened and under-diagnosed."
In the US, the old test costs around $200 to perform. The new method developed by UC Irvine Health could significantly reduce the cost, human resources and time required for the test results.
"The ability to detect infection using urine rather than blood avoids needlestick and blood sample collection, greatly reduces the cost and necessary clinical infrastructure for screening and diagnosis, helping to promote widespread adoption of the test on a global scale," Dr Hu says.
Currently, the Centers for Disease Control and Prevention (CDC) estimates that around 150 million people worldwide are infected with hepatitis C, with around 3.2 million people in the US. Effective screening and fast diagnosis are critical for treatment and controlling transmission.
Detection is crucial as people with the HCV infection often don't display symptoms until they are severe such as fibrosis, cirrhosis, or liver cancer.
The CDC recommends screening tests for high-risk patients, including intravenous drug users, and individuals who had blood transfusions before 1992, as well as those born between 1945 and 1965.
"Those who are HCV infected can now be cured, before a further liver injury and complications develop, but only if they are diagnosed," Dr Hu says.