Monday, March 14, 2011

0 Books: Mini Review on "Bull's Eye"

I've been reading bits and pieces from Bull's Eye: Unraveling The Medical Mystery Of Lyme Disease.

Someone told me it may be a frustrating read, so I was prepared for that - but it hasn't been that difficult to get through, actually, once you get past the fact that the author can write about Alan Steere more matter-of-factly than anyone I know.

That's one of the main criticisms I've heard other Lyme patients who have read it have about the book - but after reading a huge chunk of it, I'd have to say that it is more balanced about discussing the controversy than I thought it would be and that much of it focuses on things other than Steere: the history of Lyme disease in Connecticut, history of Borrelia in Europe, general research on Borrelia burgdorferi, epidemiology, difficulties in diagnosing Lyme disease, problems with serological testing, the Dearborn criteria, coinfections, shortcomings in the IDSA view of Lyme disease, the Ed Masters story, experimental treatments, genomes, vaccines, and legal issues.

And it's an easy read, for what it's worth - for the most part, people who aren't knowledgeable about Lyme disease or its controversy can jump right in and begin getting an idea of the big picture pretty quickly.

One of the things that makes it readable is the author, Jonathan Edlow, MD,  can outline procedures using metaphors and analogies in a basic way so that those reading this kind of material for the first time can 'get it', and I've found  the Ambiguity in the Lab chapter to be one of more interesting reads because of how it was written.

In the book, the author describes for the reader how Western blot tests are done for Lyme disease:
"Like the ELISA, the Western blot tests for antibodies, but it allows the laboratory to find precisely which antigens a patient's blood contains antibodies to - not just whether there are any kinds of anti-borrelial antibodies. 
First, the B. burgdorferi is put into a detergent to break up all its proteins. Each of these proteins has different sizes and each has a slight electrical charge. These proteins (antigens) are placed on a gel to which an electrical current is applied. The proteins then migrate across the gel, which is full of nooks and crannies, rather like an English muffin. Because the proteins have different sizes, they move through the gel at different rates, the larger ones moving more slowly than the smaller ones. After a certain amount of time migrating with the electrical current across the gel, the proteins from the B. burgdorferi have traveled different distances. 
Imagine a massive jungle gym with evenly spaced bars going every which way. A group of people who are four to seven feet tall are instructed to start at one end of the jungle gym and travel through the latticework as far as they can in five minutes toward the other side. In this group of people, ten are exactly four feet tall; ten are exactly four feet, six inches tall; ten are five feet tall, and so on - such that there are seven groups of ten people who are all the same height. 
Since the spaces between the bars of the jungle gym are uniform, the smaller people will be able to travel faster across this jungle than the larger, heavier people. When the five minutes are up, the larger people will be closer to the start and the smaller closer to the finish. Assuming that the participants are equal in their abilities, at the end of the five minutes, the seven groups will settle out in seven distinct regions of the jungle gym. If one were to take a picture of the apparatus at the end of the five minutes, it would show seven bands - clusters of people of the same height - interspersed with bare areas of the jungle gym devoid of anyone.
This is what happens to the proteins from borrelia in the Western blot. They migrate across the gel, through the network of obstructions, at different rates on the basis of their molecular weights. After a specified period of time, the proteins are clustered on the gel at specific regions. They are then transferred (blotted) onto a special kind of white membrane. Specific antibodies (attached to a dye and so that they can be seen) will bind to specific borrelial proteins, and colored bands will appear on the white membrane."
Edlow explains other processes and definitions by using metaphor and analogy throughout the book, making it easier to visualize them. He uses the idea of a machine to sort different kinds of fruit to explain what sensitivity and specificity mean in terms of blood tests detecting infection, and uses different models and makes of cars to help describe cross-reactivity in testing. The way he puts things makes it easier for people with no prior knowledge of Lyme disease and testing to understand certain concepts that they can later build on.

There are other reasons I like this book, and a few reasons I don't, but I wanted to take time aside to share this one aspect.

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