Re: Weird hepatitis B test results

On Aug 18, 7:30 pm, ri...@xxxxxxxxx (Rich Wales) wrote:
David Rind wrote:

> Five years is probably too short. This can certainly occur
> over 20-30 years, and probably over some shorter time frames.

I'm puzzled right now as to when and how I might have been exposed
to hepatitis B. I've never been sexually promiscuous or a drug
abuser, and I've never had a blood transfusion. Assuming for the
moment that I may somehow have had hepatitis B years ago, what
would be some other, less common ways I might have been exposed?

Rich Wales ri...@xxxxxxxxx http://www.richw.org
*DISCLAIMER: I am not a doctor. My comments are for discussion pur-
poses only and are not intended to be relied upon as medical advice.

The virus lives outside the body for a long time and household
contacts are a prime source of exposure. I would concentrate on not so
much how but who. Obviously the concern is a family member such as a
parent, brother or sister who is a carrier or has chronic active
hepatitis. The goal is to monitor carrier patients and to treat
chronic hepatitis patients.

Prenatal hepatitis B antigen testing is mandatory and therefore your
spouse would not be such a candidate for chronic carrier state and as
David mentioned it probably happened years ago and so extended family
is more a probable concern. If it happened during high school sporting
activities then there's not much you can do about it.

Davids point is well taken concerning false positives with one
addition, biological false positives are not as prevalent as
mechanical false positives. The mechanical causes are much more common
and policies and procedures are included with each test system as to
how to minimize or eliminate these results. These aberrant results
should not make it to the final report. These results are usually
within the low positivity gray-zone area and usually must be repeated
twice after proper handling of the initial specimen. The two out of
three results win. Fortunately or unfortunately the S/CO specimen to
cut-off ratios are not reported but simply the interpretation.
Discordant results must always be interpreted within the clinical
context of the patient as he mentioned the high risk groups concerning
the low probability of it being a false positive. A repeat specimen
is always recommended as it can validate results from a lab error
perspective, technical precision aspect.
It was repeated in this case and so the technical aspects of the test
is repeatable.

If a clinician where to challenge the result or question it then a
send out for an alternate methodology or a search for heterophil
antibodies may be in order although because of it's typical nature of
the sole marker being present most just move on. I don't have an
answer as to why only anti-HBc persists longer than anti-HBs does. It
might be that one part of the virus is more antigenic than the other
part.

.

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