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  #1  
Old 03-01-2005, 05:09 PM
CC CC is offline
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why can't I donate blood with Hep b antibodies?

Eleven years ago, much to my surprise, I got a letter from the local blood donation drive informing me I was never going to be able to donate blood again, because hep B surface Antibodies were detected in some blood I had given. They said that sometime during my life (I'm freakin' 62, fer cri yi) I had had contact with hep B. I was negative for hep B surface antigens, negative for hep C antibodies. They said that there is a concern that I might have also been exposed to other hepatitis viruses that they cannot test for. OK. 11 years have passed. Can someone in the Doper community tell me if I'm ok to donate again? This was one of my favorite societal obligations, along with voting, and that, as it turns out, isn't very satisfying anymore. Are there better Hepatitis tests now? Am I considered safer now? What's the straight dope on this? Thanks. xo C.
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  #2  
Old 03-01-2005, 05:14 PM
Tenar Tenar is offline
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The safest thing to do would be to check with your local Red Cross (or other) blood donation center and ask them.

I used to be ineligible to donate because if I answered all of the HIV screening questions honestly, I would be eliminated even though I knew conclusively (based on several tests over a period to a couple of years, along followed by a long period of abstinence) that I was NOT HIV positive. I recently (a year or so ago) noticed that, using the current questionaire, I would pass with flying colors.
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  #3  
Old 03-01-2005, 05:47 PM
Loopydude Loopydude is offline
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Even in the absense of detectable antigen, it's not a stretch to suspect you've been exposed if there's detectable antibody against HepB antigens in your serum.

It's also worth considering that antibodies are not perfectly specific for a particular protein. Sequence and structural similarties with other proteins may allow a particular monoclonal antibody to cross-react with any number of other proteins that contain a motif sufficiently similar to the antigen that generated the immune response you clearly manifest. Whether it's due to true Hep B exposure, exposure to another similar virus, or something else entirely that just happens by pure chance to be similar, is difficult to determine, and well outside of the means of the blood banks attempting to regulate the safety of their inventories to establish. In all but the most benign permutations of the latter case, you may pose a risk to a recipient; there's just no practical way to know for sure. They have peformed an immunoassay that gave a positive result, and based on that result have acted according to their guidelines. Their guidelines do leave certain questions unanswered, but it's no feasible for them to answer those questions, so they must remain moot.

Just because of where I've been in the world, and for how long, I cannot now donate blood (CJD risk-assessment preculdes it). I'm in the same boat, essentially, and sympathize with your disappointment. Unfortunately, there's nothing for it but to seek other outlets for performing civic duties.
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  #4  
Old 03-01-2005, 05:47 PM
Nunavut Boy Nunavut Boy is offline
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Here is a quote from the AABB (American Association of Blood Banks) Technical Manual (the Bible for blood transfusion related stuff)

Quote:
After initial HBV infection, a proportion of patients fail to clear infectious virus from the bloodstream and become chronic carriers for years or life. HBV carriers produce, in addition to the infectious viral particle, large amounts of noninfectious envelope protein detected by the assay for hepatits B surface antigens (HBsAg). The risk of becoming an HBsAg carrier is strongly age-dependent. Of those infected with HBV as adults, about 5% become chronic HBsAg carriers, while 95% recover completely and develop protective antibody against HBsAg.
So, theoretically, even if you WERE a carrier, it SHOULD STILL be detectable. But in blood banking, this is an unnecessary risk when we can find other donors with much less possibility of HBsAg in their bloodstream.

You should be reassured about the steps taken to keep the blood supply safe!
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  #5  
Old 03-01-2005, 06:07 PM
Qadgop the Mercotan Qadgop the Mercotan is offline
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I once had a patient who was HIV positive on the Western Blot. Thanks to modern anti-virals he was able to reduce his viral load so low that it was "undetectable" (a common occurance). He then proclaimed himself cured of HIV (sadly untrue, even when the virus cannot be detected), and demanded loudly to be allowed to donate blood at the Red Cross.

Anyone want him in the donor pool?

The principle with Hepatitis is the same, as Nunavut Boy has pointed out. Just because the virus is undetected doesn't mean that the virus is absent.

Why risk the blood supply? Just so someone can feel good about donating?

QtM, MD
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  #6  
Old 03-01-2005, 09:27 PM
KarlGauss KarlGauss is offline
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Does this mean that people who have received the Hep-B vaccination are ineligible to donate? Or only those with antibodies but who can't provide a vaccination history?
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  #7  
Old 03-01-2005, 09:55 PM
JillGat JillGat is offline
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You can still donate if you've been vaccinated against Hepatitis B. They can tell the difference.
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  #8  
Old 03-01-2005, 10:11 PM
JillGat JillGat is offline
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I should clarify that. It is possible to test positive for Hep B surface antigen for a short period of time after having been vaccinated. Probably be safe to donate a few months after you've had your last shot.

To the OP, are you sure you tested positive for "surface antibodies? I thought blood banks only tested for Hepatitis B surface antigen (HBsAg) and Hepatitis B core antibody (anti-HBc)
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  #9  
Old 03-01-2005, 11:32 PM
Loopydude Loopydude is offline
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That is my understanding as well. If I recall correctly, to be negative for HBsAg, but positive for anti-HBc (Hep B core IgM, I think) can mean a false positive, recent acute infection, or chronic carrier with unmeasurably low circulating HBsAg. They typically don't look any further, though there certainly are tests (like PCR-based viral DNA assays as well as liver function tests) that can more rigorously establish chronic disease or lack thereof.
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  #10  
Old 03-01-2005, 11:51 PM
KarlGauss KarlGauss is offline
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Quote:
Originally Posted by JillGat
To the OP, are you sure you tested positive for "surface antibodies? I thought blood banks only tested for Hepatitis B surface antigen (HBsAg) and Hepatitis B core antibody (anti-HBc)
Quote:
Originally Posted by JillGat
To the OP, are you sure you tested positive for "surface antibodies? I thought blood banks only tested for Hepatitis B surface antigen (HBsAg) and Hepatitis B core antibody (anti-HBc)
This is why I was confused. I thought the vaccine elicited anti-surface antibodies and so would have been surprised if potential donors were disqualified on the basis of such antibodies being present. Still, I didn't know that blood banks looked for anti-HBc.

Do they still check for elevated transaminases?
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  #11  
Old 03-02-2005, 01:04 AM
nevermore nevermore is offline
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now I'm curious, what's the difference between core antibodies and surface antibodies? core = circulating and surface = on B cell surface?

if that's the case, I wouldn't expect surface antibodies to last very long, since any given cell's got a pretty limited lifespan. so I'm probably wrong. anyone?
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  #12  
Old 03-02-2005, 01:28 AM
Loopydude Loopydude is offline
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I'm no virologist, but I believe Hep B (as well as the other HPVs) is composed of a few viral coat proteins (the surface antigens) making the outer layer of the capsid, a nested layer of proteins surrounding the viral genome (the core proteins), as well as the virus' own DNA replicating enzyme.
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  #13  
Old 03-02-2005, 08:18 AM
CC CC is offline
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from the original letter...

This is from the original letter I received: "In testing the blood that you donated we found that the test for an antibody to Hepatitis B virus (HBV), the 'Anti-Heptatitis B Core Antibody' test, was positive...Other hepatitis-related test results include: Hepatitis B Surface Antibody (a measure of immunity to HBV): positive...Hepatitis B Virus Surface Antigen (a part of HBV itself): negative." I think I inadvertently led some folks astray by not providing sufficient information. After re-reading the posts, it sounds as if I have evidence - both core and surface - of antibodies to Hep B. That tells me that I must have been exposed to the antigens of Hep B at some point and my body responded to it by making antibodies. But I still don't understand why that makes me a risk if I have no evidence of infectious particles, i.e. virus or antigens.
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  #14  
Old 03-02-2005, 08:31 AM
Loopydude Loopydude is offline
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I'd say if you're positive for antibodies for two kinds of antigen from the same virus, the chance that it is a false positive is so remote as to be not worth considering. If I might hazard a guess, you're probably a chronic carrier with too few circulating viral particles to be detectable in the bank's immunoassay. A test for circulating HBV DNA will clinch it, and it might not be a bad idea to get one.

As pointed out above, low titer is not no titer, and no titer is the only kind that can't lead to infection of a recipient. It's perfectly reasonable, given your serology, to conclude that your blood does pose an unacceptable risk. Even in the absense of a positive result in a sensitive PCR-based assay, it would still be inappropriate to give your blood to another person. You've clearly been exposed to competant virus in amounts sufficient to elicit the sort of immune response characteristic of infection. Once you've been infected, that's it; no more blood doning. It's simply too dangerous for the folks downstream. Certainly, the lower the viral load, the lower the chance of infection, but nobody wants to play Russian roulette.
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  #15  
Old 03-02-2005, 03:27 PM
Billdo Billdo is offline
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I would check with your local blood services.

Sometime in the early 1990's, I got a similar letter from the New York Blood Center regarding a positive test for something related to one or another variety of hepatitis (I don't recall the details). I was checked out by my doctor, who found no problems.

Several years later, I got a letter from the blood center saying that I could donate again. When I went to donate again, they checked in their computer and said I was fine to do so.

I don't know why they changed the policy, but you should check with your local blood organization to see if you fall in the same category.
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  #16  
Old 03-02-2005, 03:58 PM
USCDiver USCDiver is offline
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I'm going to try to recall my microbiology from 3 years ago here.... (basics: antigen is the protein on the virus that illicits an immune response; antibody is what the body produces to enable it to recognize and eliminate future exposures to antigen)

The HBV vaccine consists of HBV surface antigen (HBs) which the body produces an immunologic response to, generating anti-HBsAb (antibody).

Infection with HBV exposes the person to both the surface antigen and the core antigen resulting in both anti-HBsAb and anti-HBcAb. The vaccine contains no core antigens (it is not a live virus immunization), hence it is impossible to have Anti-HBcAb without infection.
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  #17  
Old 03-02-2005, 04:48 PM
odaran odaran is offline
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Personal story (maybe TMI)

I am on the Indefinatly(sp?) Deferred Donors list and I did not even get my blood tested.

About 6 years ago, I got mono and had elevated liver enzymes in my urine. I had gone to the doctor because of the color (kind of a strained tea look) and he sent me to the hospital to get an ultra sound on my gall bladder. When he called the hospital to let them I was coming, he mentioned Hepatitis and I freaked. I did not perform any behavior that could have exposed me(that I knew of) and he informed me that was a catch all term for problems with the liver(hence the dicoloration).

After sitting for 2 hours, the ER doctor told me I had mono.

Fast forward 5 years later, I was going to donate blood and they asked if I have Hepatitis. I told them the story above and was informed that the way the rules are written, I could not donate blood now or ever, until the rules changed.
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  #18  
Old 03-02-2005, 04:57 PM
ouryL ouryL is offline
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You can donate blood.

Some of the blood plasma places welcome hep positives for the antibodies.
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