Friday, April 04, 2008

Dr. O’Leary’s bull, or when “normal” isn’t normal

I keep my CLL history -- things like CBC results, FISH tests with xeroxed blotches that are supposed to signify something, lengthy dissertations by experts and not-so-experts upon my condition -- in file folders, organized by year.

The year of diagnosis, 2003, doesn’t have much in it. By now, in 2008, the files are 2" thick when stacked on top of one another. The year 2007, in which autoimmune hemolytic anemia greeted me like the Huns greeted Rome, accounts for fully half that thickness.

And speaking of thick, let’s open that file for a minute, shall we? I recently got the complete physician’s notes from Dr. O’Leary, the man who managed, and then mismanaged, my AIHA. O’Leary was nothing if not thorough in these reports, each titled “Follow-Up Office Vis
it” and most of them making reference to my node-filled “bull neck.” Well, moo. Or snort. Or something.

I remember a couple of times
during these visits talking to O’Leary about my haptoglobin, a protein that people hip to the terminology abbreviate as “hp.” When your hp tanks, as measured by a blood test, you’re in trouble. When red blood cells are actively being destroyed, hp disappears faster than it is created.

I had noticed, at one point during my travels, or travails, that my hp was declining, even though it was within the “normal range” (or “reference interval”) of 34 to 200. I had the sense that this could be a problem, and I asked O’Leary about it. He replied that there was no need to worry, it was within the normal range.

Later that day, after I left, he made his dictation, which contained this comment:

“We discussed at length his other laboratory tests. His haptoglobin remains normal, although it is drifting down a bit. It was around 170, then it was 67 and now it is down to 49, although it is normal.”

Well, you guessed it: It continued to drift down. Four weeks later all hell broke loose and the AIHA was pounding at the city gates again.

There are a number of lessons to be learned here. One: Patient, trust your intuition. Two: Just because a result is “normal,” that does not mean an important trend ca
n’t be identified and appropriate action taken. Three: I really wonder whether O’Leary should be practicing medicine. In the United States. On people. (Drifting down “a bit”!)

But let’s focus on number two: Reference intervals, normal values, and the like are not licenses to not worry.

Some of this depends on what is being tested: ZAP-70, for example, is positive once it passes a certain point, usually 20%. It doesn’t matter whether you are 22% positive or 82% positive, you are positive. As far as I can tell, and I once asked Dr. Terry Hamblin about this on the ACOR CLL List, the level of positivity does not count as much as the fact that you are positive.

Red blood counts are another matter. Many of us see our hemoglobin d
rifting down as the disease progresses, a result of marrow impaction. Your HGB might be 15.6 one year, 14.3 a year later, 13.1 a year after that. These numbers are all within the “normal range” but they signify a trend that tells us something important.

The same is true with haptoglobin. That is the point of this pos
t. In your test results, look for trends. Do not be lulled into thinking that just because the result is still “normal” that you don’t have anything to worry about. (I know it is especially hard to argue with doctors about this sort of thing. O’Leary may have thought I had a bull neck, but I think he was bull-headed; he tended to dismiss my concerns, which almost ended in disaster, and which did end with me switching doctors.)

I have alerted Dr. Belle to all this, and we are watching my hp for any
signs of a downward trend. We are also keeping track of my LDH, which would increase with hemolysis, and my bilirubin, which would do so as well.

And so far, so good. I continue to show improvement in the red counts, which are either "normal” now, or tantalizingly close. The icing on the cake is that my lymphocyte count has slowly drifted downward since my last cycle of chemo four months ago.

My only discomfort is in knowing that somewhere out there Dr. O’Leary is telling a cancer patient not to worry, that their test results -- despite evincing a trend that, if it had a mouth, would bite them -- are “normal.”


Richard said...

Hi David,

Your comments fit exactly with my experience. I think GP's must be trained to only trigger into action once measurements go outside accepted limits.

I think whoever makes software for GP's should put in a trend detection algorithm as well as a threshold trigger. I'm sure they would detect a lot more illnesses earlier if this was done.

My RBC has been tracking down since before my CLL diagnosis and my MCV has been tracking up, but they are both just still in the 'normal range'. The platelets on the other hand have been roughly constant. The lymphocyte count also appears roughly constant to my GP, but when corrected for my physical activity, it is also increasing steadily. I'm guessing I've got chronic AIHA rather than a marrow problem. Having seen the recent work on cytopenias and prongnosis, this would appear to be the more optimistic interpretation. However as your case shows AIHA can turn really nasty when it feels like it

Is your AIHA hot or cold?

Lang mae yer lum reek


David Arenson said...

I got a little concerned when I heard that my lum could be reeking, but Google has set me at ease.

I don't know what makes some doctors ignore the obvious, except perhaps laziness, or a past experience in which things did not turn out for the worst. This is called "leaving the patient to chance." At the time of the hp discussion with Dr. O, I was on absolutely no treatment for AIHA, no steroids, no nothing. Would it have been prudent to put me on steroids and see if the hp trend reversed itself? [Rhetorical question]

Richard, if you think you have a "touch" of AIHA, I would suggest you get some tests done before that touch turns into an embrace. These tests would include hp, reticulocyte count, DAT (Coombs) -- to see if you are low in the first, high in the second, and positive in the third.

Tich tor ang tesmur!

Anonymous said...

This sort of thing could also be a case where, even if trends are truly indicative of an impending problem, given the nature of this disease it is not yet time for counteractive measures. And since one can't be sure at that point whether the trend is significant or not, perhaps the most humane attitude for the doctor to portray is, "The counts are still normal, so there's no cause for worry at this point."

David Arenson said...

The previous commenter makes a valid point: Just because one sees a trend, it may not be time for countermeasures. That is where the *art* of medicine comes in. I have come to understand a lot more about AIHA since the day of O'Leary's dictation. If you have a patient who has undergone severe and rapid hemolysis in the past, who is still Coombs positive, and you see the hp numbers declining significantly -- and the patient is on no maintenance tx such as steroids -- a proactive measure at that point is only prudent.

Terry Hamblin said...

David, you have spotted a problem with many doctors. In many cases single measurements are not very informative and the trend is more important.

In my experience AIHA in CLL is poorly undersood and managed by most doctors.