Donated blood... HTLV-positive test results?

Miscellaneous and Personal Stuff I Must Share
1

I donated blood last January, no problems. I donated again in September, and a few weeks later I got a letter from the Red Cross saying they had rejected my donation because of abnormal blood test results.

Their test for antibodies to the “HTLV Type I/II” viruses came back positive. So they automatically did a “supplemental” test that’s supposed to be a more specific test for these viruses, and that test came back negative. So, the letter says, I don’t actually have antibodies to the HTLV viruses. But just in case, we threw away your blood donation, we put your name on a list of banned donors, and please don’t ever donate blood again.

My feelings were hurt that they threw away my blood, because I had a heck of a time donating it (bruise the size of an egg on my arm).

I looked up HTLV, and it’s very rare in the US. Mostly it’s found in Asia, particularly among intraveneous drug users. It’s transmitted by exchange of body fluids. I have done nothing to be at risk for this, especially between January and September of last year. One of the HTLV viruses doesn’t seem to cause any health problems. The other one increases your risk of a nasty form of leukemia.

I was a little freaked out, so I went to see my doctor and he repeated the blood test, and got the same results: general test was positive, specific test was negative. He sent me to a doctor who specializes in infectious diseases. That doctor said I don’t have HTLV, that instead something in my blood just looks like the antibodies to HTLV, and fools the general test. He said this happens occasionally, he didn’t know why. It might go away, or I might test this way forever. I’m supposed to get retested this month to see. (He said it also happens with HIV tests, and those people get very upset and it is difficult to assure them that they don’t have HIV.)

Oh well, I never enjoyed giving blood anyway. I’m hard to stick. I did it a couple of times a year because I thought it was the right thing to do. I guess now I can abstain without feeling guilty.

Ara-Alon

2

Ugh, HTLV is one of the several pathogens I don’t ever want to contract.

looks in the -80 and sees the HTLV viral stocks

Some days my job really sucks.

3

The exact thing happened to me in 1997. I got two opinions from two docs, never traveled out of the country, and have not been symptomatic (thank goodness) since. It’s a real bummer, since I liked the smug feeling I got after donating. I’m glad to see that I am not alone.

4

I’m sure we can find something else for you to feel smug about. Have you considered veganism, or getting a hybrid? :wink:

5

This sort of thing makes me definitely second guess the idea that we are so really in need of blood. Even if you didn’t keep it with the rest, you’d think that, with low blood supplies, they’d keep it for emergencies when there’s nothing else to be used.

I mean, how great can the risk be that you actually have the disease even though the more specific test shows you don’t?

6

This stuff always makes me wonder about those who are poorer or less proactive in their health, lacking the funds or know how to get confirmation they just assume the result is real. Scary to think about.

7

Well gay people are told not to donate even if their blood is 100% free of disease. Think how they feel

8

When they give a blood transfusion, it is almost always an emergency, practically by definition.

I suspect the reason they don’t keep the blood has to do with liability issues. Imagine if they used it and there WAS a problem with it. It could cost them millions.

9

You know who else can’t donate blood, ZOMBIES!

10

Likewise, except maybe for the smug feeling (my reaction was usually a sense of relief that they’d leave me alone for a month or so — I have one of the rarer types, and could almost set my watch by the “it’s time to donate again” calls).

The only thing on the list of potential causes that could have applied to me was an extremely rare reaction to a flu shot. Kind of sucks that trying to take care of myself makes me persona non grata to the blood bank, but that’s the way the corpuscle bounces.

11

I’m going through the same thing, only with hepatitis C. There’s no chance I have it, but I still have to check it out, and I can’t ever donate blood again. The Red Cross (for good reason) doesn’t want to take the slightest chance with the blood supply, even if the danger is unlikely.

12

Maybe they can save all the questionable blood just for you.

13

Well, it’s whatever the false negative rate on the specific test is times the incidence of people with the disease who get a positive on the first test. That’s almost certainly way higher than the false positive rate on the first test combined with the incidence of the disease in the general blood-donating population, so it makes lots of sense to throw the blood out. Even if it’s very unlikely the blood is bad, the cost of giving someone infected blood is so high that it even a relatively small probability cancels out the value of using the blood.

I have a friend who can’t donate because his blood generates a positive on the standard HIV antibody test. He’s not HIV+, but it takes a more expensive test to verify that, and even with that test, the very low chance that he has HIV is still too high for it to be economical for him to donate blood.

14

Definitely people exist who test falsely positive for pathogens, and for whatever biological reasons, they will continue to test falsely positive, which will prevent their blood from being used. The blood center has donors fill out surveys to assess their risk level (travel to countries with endemic disease, M/M sex, ID use, etc.); the reason that this is done is because no blood test exists that has zero window (i.e. the amount of time between infection and detection). If you consider the window periods for different diseases and the claims that are made (e.g. most people test HIV positive in 25 days, but 99% test HIV positive within three months), you’ll see that even the window periods themselves are not concrete. Manufacturer of tests claim that their tests have improved so much that cases of people eventually testing positive who initially tested false negative outside the window period don’t exist anymore. In turn, people rely on the test manufacturer’s window claim to declare that they test truly negative once outside the window period. HTLV is notorious in this aspect, because unlike HIV, HTLV doesn’t cause massive viral reproduction, which in turn doesn’t cause much antibody production, which in turn is harder to detect in testing. The blood banks use 51 days as the window for HTLV antibody detection, but doctors will tell you to test out to six months, and some will even say test longer. All of this window ambiguity is the reason that blood banks are trigger happy when it comes to discarding blood. A research paper on NY blood donors showed that as much as 25% of them had components of the HTLV virus in their blood, even though their blood tested HTLV antibody negative - does that sound like the testing is catching everything? And this talk about HTLV being an “overseas” illness should remind us that planes full of people commute back & forth to other countries every day, allowing pathogens to travel. We didn’t have HIV in North America until someone took a plane from Africa to Haiti, and we didn’t have HTLV in Brazil until the Japanese emigrated there.

15

Having been in the position of needing to try to urgently obtain blood for a hospital patient who had so many rare antibodies that there was, literally, ONE active donor in the state who was compatible with that particular person, I would definitely say that there is a real need for anyone who can donate to do so. You never know if your blood might turn out to be essential for a particular patient.

However, I don’t blame the blood banks for being very cautious about rejecting blood. There would be lawsuits and a public outcry if someone ended up with a disease in circumstances that could have been prevented. It’s bad enough when, despite all the screening, there are those rare cases of people contracting a disease from blood transfusions.

16

And yes, disease via transfusion still occurs, even though it is rare, it is not non-existent. No one wants to be on the receiving end of HIV, HTLV, HCV, etc. simply because the protocol to discard questionable blood wasn’t adhered to.

17

I kind of hesitate to bother to post this, because it’s at the tail end of a zombie, so I doubt that it will reach a wide audience, but what the hell.

When designing a test, you have to decide between high false positive rates and high false negative rates. Obviously, a perfect test would enable you to correctly distinguish between positive and negative correctly 100% of the time. But in the real world, it turns out that a lot of the time, you’re setting a more or less arbitrary cut-off line and saying “this is where negative turns into positive”. And you have to be very careful about where you put that line.

So screening tests are done first. These are typically cheap, easy and quick, and they are specifically designed to have a very very low false negative rate - that is, you want to be very certain that no one who actually has the disease sneaks through. The tradeoff for this is that you’re going to have a relatively high false positive rate - lots of healthy people will be flagged as being possibly infected.

You can then take these putative positive people and do a more sensitive diagnostic test. These are typically more expensive and take longer. They should ideally be based on a different technology, so that you’re testing samples in two different ways. With these tests, you’re going for a much lower false negative rate - you want to make sure that if the patient tests positive, they really are positive, because they’re about to undergo expensive, inconvenient, and sometimes painful treatment for the disease.

That’s the general strategy of testing blood, and that’s why you get a lot of false positives reported, as in the original OP. Now, as to why he’s banned forever from giving blood, well, I think that’s more of a political issue. If someone ever caught a disease from a transfusion, and it was shown that the donor had once been flagged as a possible carrier, but they took his blood anyway, the shit would hit the fan. And, since no diagnostic test can be 100% accurate, they can never be completely certain that the initial positive result was false.

18

The exact same thing happened to me in 2008. Same pattern of positive then negative. The only difference is that I got really freaked out after the testing at the doctors came back “reactive” again. They didn’t do the confirmatory testing, where they look for the actual virus like they did at the blood bank, probably because my insurance wouldn’t pay for it. The NP and even the other nurses plus a dr there all seemed to think that A, I tested positive because what I really had was HIV, or B, that I should just trust the confirmation test the blood bank did and stop freaking out. It was a really horrible experience and I haven’t gone to the doctor ever since except to get flu shots or for biometric screenings. The thing that concerns me the most obviously, is being hiv positive. But then even if I am only positive for htvl, it would be an awkward thing to explain to anyone, especially someone that wants to be involved romantically with you. I am single mother of a young boy, and I guess another thing that worries me is having either of these conditions and not being able to cope well with it which would in turn affect my parenting. I wish I could have been as dismissive as ara alon when it all happened 5 years ago or that I would have just kept going to doctors, regardless of the outcome, truly positive or not. I still think its possible I may be sick, and the lack of confirmation has caused me significant stress. I don’t date as I’m afraid that I may be carrying something I may give to someone else, even though I am cautious and firmly believe in always using protection. Also I would hate to develop an emotional attachment to someone, then eventually have to deal with the complications of having to explain what’s wrong with me. I can only imagine how hard it is to be rejected by someone you care about because you’re sick.

BTW, I don’t blame blood banks for being cautious and rejecting some donors. I just wish that when things like this happen they would be more involved with the individual and possibly arrange for a meeting in person. Follow up testing through the blood bank would be a good idea as well. This way they could keep track of situations where people eventually DO truly test positive, and people who previously received that donors blood could be informed of the possible exposure. Also, face to face follow ups are a lot more reassuring than a freaking letter saying we don’t want your blood anymore because it may have “cooties”, but yes its safe to assume that you are most likely not infected.
:frowning:

19

I have a familt member who was positive with htlv …n we believe is when tha person got shot on the leg n lost a lot of blood…could that cuz the issue…

20

Rosa, could you clarify the story a bit?

You have a family member who tested positive for HTLV. This person was . . . shot in the leg and lost a lot of blood? Did they receive a blood transfusion?

There are two things going on here. The first is how your relative was tested for HTLV. There are two ways to test: the faster, easier, and cheaper is to test the blood for antibodies to HTLV. Antibodies indicate that that a person has been infected and their immune system is responding to the infection. However, the test isn’t perfect. It could pick up on something which makes it react as if there are antibodies. The second type of test looks for the virus itself. It’s more likely to give an accurate answer, but it’s more expensive and time consuming.

HTLV is transmitted by blood, which means a person can become infected if they have sex with, share IV needles with, or receive blood from an infected person. The thing is, all donor blood is tested for HTLV (it may cause some forms of cancer, so we really, really don’t want it in our blood supply). As the original poster reported, even a likely false positive (the test says you have HTLV antibodies, but you really don’t) is not questioned. The blood is disposed of and never used.

So, your family member may have tested positive, but not really have it. In order to be sure, they should see a doctor and ask for the second, more specific test. It may be that your family member does have HTLV. If they do, they almost certainly did not get it through a blood donation. Whichever, your family member needs to see a doctor to a) confirm their status and b) determine treatment if they are positive. HTLV can cause lymphoma, a highly treatable form, but it has to be caught in time.