How to diagnose a hepatitis E infection

In this lesson, Dr. Wonnerth uses case studies to show you how to use case history and lab results to diagnose a hepatitis E infection. Learn the serological markers that correlate with HEV infection and how they behave differently in immunocompetent vs immunocompromised patients.

Lab investigations are crucial for diagnosing viral hepatic infections, but they can be tricky to interpret. See more cases of viral hepatitis in our course Viral Hepatitis Lab Essentials. Taught by Dr. Anna Wonnerth– Certified Family Physician and Laboratory Medicine Specialist at the Hospital of Wiener Neustadt, Austria–you'll be a viral hepatitis expert in no time.

[00:00:00] So now, let's meet some patients so we can put to work what we have learned about hepatitis E diagnostics. Our first patient is Hannah. She feels sick and had to vomit at home, she's feverish, and her skin has a yellowish color, her symptoms started one week ago. Four weeks ago, she came back from Mexico when she visited family. Obviously, we think about hepatitis. Let's order lab tests. In Hannah's lab report, we can see that her liver enzyme function is

[00:00:30] significantly elevated. Furthermore, her hepatitis E tests are positive. Hepatitis E RNA is also detectable. So, what's your diagnosis? Hannah has no history of immunosuppression. So, let's take a look back at the graphic, dealing with immunocompetent patients. Her ALT is very high, which signifies serious liver damage, anti-HEV IgM and IgG are both positive, and we could detect RNA in Hannah's stool. Based on these results, we can conclude that Hannah is most likely

[00:01:00] in the early phase after infection. So, Hannah is suffering from an acute hepatitis E infection. Let's see our next patient. Our second patient is Pete. He suffers from abdominal pain of recent onset. In the lab report, we can already see elevated liver enzymes. Pete received a lung transplant eight years ago. Currently, he's on immunosuppressive therapy. Furthermore, he tells us that he's a passionate hunter. Based on Pete's history, we include hepatitis E screening in our lab report.

[00:01:30] We can see that his liver enzyme function is significantly elevated. His anti HEV antibodies are negative, however, the lab detected HEV RNA in Pete's stool. What does that mean? Since we know that Pete is taking immunosuppressive medication, we should consider this in interpreting his lab results. We know that immunocompromised patients can have problems producing antibodies to the virus so, in Pete's case, it is essential to measure RNA. His lab report shows elevated ALT levels, as a sign

[00:02:00] of liver damage but negative antibody tests. However, there is RNA detectable in his stool. Pete is suffering from an active, ongoing HEV infection. Based on the laboratory findings, we cannot determine when Pete was infected. It may have been recently or more than six months ago. However, it is not important to know that. What is important is that Pete gets appropriate treatment and follow-ups. Congratulations. Now, you can handle hepatitis E lab results.