Wednesday, April 2, 2008

"I never drink . . . wine," or core antibodies

Today is blood drive day at work, but my blood donation days are over thanks to an unreliable screening process and FDA cautiousness.

I've been a blood donor since I was first eligible. I was turned away once in Hamburg, New York, because my blood pressure was high. As I dripped sweat onto the floor, I asked naively, "Would riding a bicycle three miles uphill make it high?" Undoubtedly bemused, the nurse directed me to rest for a while, then we tried again. This time, my blood pressure was its usual laid-back self. Later, in my 20s, I was rejected once for low iron, but that proved to be a temporary condition.

I donated primarily through the Red Cross and later the University of Chicago hospitals. More recently, I've donated through an agency that performs workplace blood drives. My blood is healthy; the trouble has been getting at it and drawing it. My veins are either too deep or too small, and there seems to be only one, on the outer edge of my left elbow, that's consistently viable. We tried apheresis once, but it took too long.

At some point in the 1990s, after a donation the agency sent me a letter saying that my blood had tested positive for hepatitis B core antibodies and could not be used. This seemed unlikely to me, so I asked my doctor to order a screening. He couldn't find anything, and I wrote a rather tetchy letter to the agency with the results enclosed.

If I remember right, I donated a few more times without problem, then in the early 2000s the screening once again revealed the presence of hepatitis B core antibodies. By now, I was a little upset because it was clear to me the screening was flawed. I did not try to donate again until November 2007; I was under the impression that I still could.

No.

I received a stern letter from the agency saying that, although the screening was negative this time, I have been permanently deferred as a blood donor due to two positive screenings [with negative screenings in between].

The letter was not well written, and it wasn't clear to me if this was this particular agency's policy, a generally accepted practice among blood donation organizations, or legally mandated. I did a little digging and found the following on another organization's site:

There is also evidence to suggest that a high percentage of positive HBcAb tests in healthy blood donors are false positives. The hepatitis B core antibody should not become positive because of vaccination. Donors are deferred after 2 positive occurrences.

This sounded to me like a generally accepted practice that makes no sense.

In the meantime, the agency had gotten my Social Security number wrong, and the voicemail I'd left with the corrected number had gone unnoticed. Finally, I got hold of a living being and told her that my pint had been dispensed with as no good, so my Social Security number didn't matter. "Oh, no, it's important that we have the correct number on file," undoubtedly to send to the CIA, FBI, Red Cross, the remnants of the KGB, and anyone else who might be out for my apparently tainted blood, what with the hepatitis B core antibodies that I sometimes have and sometimes don't.

I had a thought. "Can I talk to someone [a nurse] who can explain why I've been permanently deferred?" The conversation with the nurse was enlightening, frustrating, and almost amusing.

She told me that blood from a donor with hepatitis B core antibodies can't be used as it causes problems for the recipient. Right—I understand that perfectly and have no desire to make someone whose health is compromised worse. According to her, the presence of these core antibodies is not a bad thing for me, as they provide protection against hepatitis B. Right—I am familiar with the general principles behind antibodies.

I pointed out that I either have them or I don't, and it looks to me like the screening process produces a number of false positives, making it rather useless. "Yes," she conceded, "the screening does produce a number of false positives." She went on to say that it is only a screening, not a test. The screening can be affected by a number of factors, such as medication and viruses. It is the FDA that requires donors with two positives to be permanently deferred. "But," she said (and would repeat several times, even after agreeing that most likely I don't have hepatitis B core antibodies, "it's not a bad thing for you that you have core antibodies . . ." "I thought you agreed that it's very unlikely that I do?" "Yes, but it's not a bad thing because . . .," etc. "Something caused the positives."

After several sets of this back-and-forth serving match, I said, "Essentially, you're telling me that the FDA permanently defers a huge pool of healthy blood donors based on a flawed screening process that yields a high number of false positives."

Yes, that's what she was telling me, and that's what I gleaned from my own research.

Part of my rational mind understands the FDA's conservatism. With the best intentions, we don't want to make a recipient's condition worse.

The other part of my rational mind, however, knows that I'm the ideal blood donor—healthy and with no risks of blood-borne diseases from transfusions, travel, or lifestyle practices.

The nurse from the agency said they would call me if the regulations are changed and that I can still donate bone marrow and organs. Meanwhile, despite the constant pleas for blood donations, I'll have to keep my healthy blood to myself. For that, I am genuinely sorry.

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