Can autoimmune diseases cause a false positive for PBC?

[freckles1962]

I started going to a hematologist because my white bloods cells were elevated. He ran all sorts of lab work and finally got a hit on the CRP test. He also did a AMA M2 which was positive. I had a liver biopsy done and it was normal. I have vitaligo and eczema. Could these autoimmune diseases cause a positive AMA M2 test result?

[gwillistexas]

If I remember correctly, AMA has 9 codes. M2 is suggestive of PBC.

[GrittyReads]

The presence of AMAs - even AMA-M2 - is not sufficient of a positive diagnosis of PBC. Some people 'just' have AMAs - in fact, about 8% of the population. UK Blood donor statistics show that about 10% of their would-be donors have AMAs, and only about 1.5 - 2.0% of those go on to develop PBC. It has been known that I have AMAs since 1992, but I still have no sign of PBC. The AMAs were spotted in routine tests for some symptoms, and after extensive checks and tests for PBC I was told I didn't have it, but I have to have annual liver function (lfts) tests every year, just to keep an eye on it.

I have had the full checkouts repeated twice since, largely because a new-to-me GP panicked when she saw the AMA result. The most recent check was with the UK's leading PBC specialists, who finally pronounce that I don't have PBC - but still need the annual tests. I'm in my 60s, very fit for may age (just started rock climbing again), and in good all-round health.

For a positive diagnosis of PBC, 2 of the following criteria have to be present:

- the presence of AMAs (and/or):

- abnormal lfts, which are consistent with PBC (usually high ALP, ALT, GGT) … (and/or):

- a liver biopsy (increasingly fibroscans are also used) that shows PBC in the liver. *

One of these, alone, is not enough for a positive diagnosis of PBC, and diagnosis usually follows repeat tests over several months so as to rule out any anomalies. However, you should also for all other liver complaints and all other autoimmune condtions, just to be safe - my GP tested me for everything.

* NB these are the official guidelines for the diagnosis of of PBC, and your medics should be following them.

Hope this helps, but do talk to the trained advisors at the 'PBC Foundation' who run this site - link at top, or google 'PBC Foundation'.

Take care.

[2bear in reply to GrittyReads]

Hi what if ama plus alkaline phos but not the other liver markers ..

[gwillistexas in reply to 2bear]

I was diagnosed by positive AMA-M2 & elevated ALP. all others normal.

[GrittyReads in reply to 2bear]

I agree with gwillistexas, AMA-M2 plus elevated ALP, is usually enough for a diagnosis of PBC, but you should be tested over a period of time just to make sure that the raised ALP is not a brief anomaly.

When my AMAs were first 're'-noted (back in 20079?) I was tested about 3 times over 6 months, just to make sure none of my lfts became abnormal, and after that it went back to the once-a-year lft testing; but then my lfts have always been 'perfect'.

So, if your ALP is raised significantly, and has stayed raised, then it is pretty likely that it is PBC. Also, you don't mention if you have any symptoms - although diagnosis of PBC should not be just on symptoms. Nb They should also test you thoroughly, to rule out all other liver conditions, and other autoimmune conditions. Try to make sure you are seeing a really good liver specialist, preferably a PBC- expert.

Hope it goes okay.

[Yankeerose3 in reply to GrittyReads]

So, do you know if it is possible to go off of urso once you start taking it and find out you don't have PBC?

[GrittyReads in reply to Yankeerose3]

I don't know the answer to that. If you do have 2 out of the 3 diagnostic tests showing PBC, and they are confident of the diagnosis of PBC, then urso is usually for life.

There is another drug for treating PBC if you have serious, serious problems with taking Urso. However, many people now - and over the last 15-20 years - who have PBC and have been treated with Urso, would possibly not be alive if it hadn't been for urso. Now most people with PBC can live happy, full lives and die of old age, which did not used to be the case, so Urso is a Godsend to people with PBC.

What makes you think you don't have PBC? The ALP etc, (it's not the only lft/blood test marker for PBC) can go back to normal once you are taking Urso, but it doesn't mean the PBC has gone, just that the urso is doing a good job in helping your liver.

Please talk to the advisors at the 'PBC Foundation' who host this site. Their website is brilliant (see link at top of page, or google 'PBC Foundation'. Plus, as well as talking to them, it would be really good if you read all around the website, especially the section on diagnosis and treatment.

Hope this helps, take care,

Gritty.

[Yankeerose3 in reply to GrittyReads]

Thank you