The best test is a biopsy, but many people avoid it.
And as Vince Sherry reports, a new blood test may help.
Lorena Loarca will never forget hearing she was infected with hepatitis b.
She said, "you may die of liver cancer or cirrhosis in ten, fifteen years, and there's no cure for this disease. And this is the way that the doctor told me."
Lorena's initial shock was replaced with a determination to hunt down answers.
"I started thinking, 'what if I become a scientist one day, and I found the cure for hepatitis b?' I was, like, so naïve!" she said.
But Lorena did become a scientist.
And though a cure has yet to be found, her colleagues at the Pennsylvania Biotechnology Center have found a way to keep tabs on the liver with a simple blood test.
Doctor Anand Mehta said, "if you have significant scarring of the liver or significant fibrosis, that measurement is higher in the blood."
Their blood test looks for an antibody that only shows up in people with liver damage.
Doctor Timothy Block added, "and it turns out that the more liver disease you have, the more of this antibody in you, that there is."
The theory is that the antibody is targeting a bacterial sugar that's not getting cleaned out of the already-scarred liver.
Doctor Block also said, "suddenly it becomes much harder to clear this sugar, and, and you'll see more and more and more of these sugars accumulating, aggravating the liver disease."
The test clearly shows the degree of disease, with clear or white circles showing no scarring and black ones severe disease.
Doctor Mehta added, "here's a very strong positive, this patient has significant fibrosis. This person has mild fibrosis"
This tool isn't available yet, but it's moving forward.
"The next step for this would be to get it developed as some kind of assay kit or available to diagnosticians or practitioners,." said Doctor Block.
It's a test lorena hopes for, and her condition continues to inspire her work.
Loarca said, "I am planning to dedicate the rest of my life to hepatitis b research."
It's a commitment that's both professional, and personal.
This is Vince Sherry reporting.
The test will not replace a liver biopsy entirely, but encourages monitoring, and gives doctors a way to check a treatment's effectiveness.