Chronic HBV can lead to autoimmune hepatitis?

Question

Hello Dr McGovern,

I have been a life-long carrier of Hepatitis B for 40 years. My doctor believes I am an inactive carrier because my liver function tests, ALT, AST have been consistently normal. (By normal, I mean ALT < 33 IU, not like the ridiculous ULN of 55 IU reported by some labs). Viral load has never exceeded 3000 IU. Even liver biopsy shows zero fibrosis and no significant inflammation. So I guess I am very likely to remain an inactive carrier without the need for any treatment.

One lab that concerns me is this: Anti-smooth muscle antibody: positive. Anti-smooth muscle antibody titer: 1:160

My understanding is that 1:40 is barely positive, 1:80 is suspicious, and 1:160 is very suggestive of auto-immune hepatitis. 1:320 basically leaves no doubt. As you can see, my titer is right at the edge.

Other markers of auto-immune disease are negative: ANA, F-actin antibodies, AMA.

I came across an article which proposes the idea that antibodies against part of HBV polymerases may cross-react with self-proteins.

Mimicry Between the Hepatitis B Virus DNA Polymerase and the Antigenic Targets of Nuclear and Smooth Muscle Antibodies in Chronic Hepatitis B Virus Infection.

http://www.jimmunol.org/content/162/3/1802.long#ref-1

This really scares me. Does my high level of anti-smooth muscle antibodies suggest that I will eventually get autoimmune hepatitis? Have you seen any HBV patients with auto-immune disease? If so, how are they treated?

Thanks, JK

Answer

I looked up the journal article you found, but you will note that this is only a studies of laboratory phenomena...There are no liver biopsy results reported. Autoimmune disease is a diagnosis based on liver histology in most cases.

Some patients with autoimmune hepatitis have other clues regarding their liver disease, such as thyroid problems, diabetes, anemia and platelet problems....

I would not jump to the conclusion that you have autoimmune hepatitis. Would speak to your physician further. By the way, you can see this positive in patients who are overweight.