Novel blood test helps evaluate severity in rare lung disease: U.S. researchers

LOS ANGELES, Aug. 25 (Xinhua) -- Researchers at the U.S. National Institutes of Health (NIH) have found that a novel blood test can be used to easily evaluate disease severity in patients with pulmonary arterial hypertension (PAH), a rare lung disease, and predict survivability, the agency said on Thursday.

PAH is a rare, life-threatening condition that causes unexplained high blood pressure in the lungs. In early clinical studies, the researchers showed the test to significantly improve upon conventional tests, some of which use invasive tools, according to the NIH.

The new blood test measures DNA fragments shed by damaged cells. Researchers found that these fragments, called cell-free DNA, were elevated in the blood of patients with PAH and increase with disease severity.

PAH, whose exact cause is unknown, is estimated to affect less than 50,000 people in the United States, according to the NIH's Genetic and Rare Diseases Information Center.