Hi, I would like to weigh in here on a few points.
First, when the LP shows inflammation that is a "general effect" I think they would be referring to Oligoclonal Bands that are appearing in BOTH the Serum and the CSF. This means that all or most bands that appear in the CSF ALSO appear in the serum, so it can be presumed that they were produced by the immune activity out in the body and "seeped over" into the central nervous system. That really is not an unusual occurence. It does NOT - I repeat NOT - indicate that a person does not have MS. It is the same as a spinal tap result that is negative in the context of MS.
There is NO dictum in the medical literature that states that you can't have MS with a negative LP. NONE. The McDonald Criteria do not in any way state or imply that a person must have a postive LP in order to qualify for the diagnosis. The MS experts that I trust have stated categorically that a negative LP does NOT negate the diagnosis of MS. It is used as supporting evidence only when it is positive. Any neuro that "removes" the diagnosis of MS when an LP is negative is not very clued in to the realities of the disease.
There was one study back about four years ago that found that 100% of MS patients had 2 or more O-Bands. This must have stuck in everyone's mind. However, no study since has found that result. The studies very from about 3% to 10%. The older studies found about 20%. The cfurrent things I am reading about MS, and published by respected MS organizations are still quoting the 10% to 20% of MS patients will have less than 2 O-Bands.
What many neurologists fail to remember when they read studies that show very high numbers of MS patients with positive O-Bands is that studies are done under the most ideal of circumstances, especially the ones done about three years ago. That is when they were studying a new technique for helping O-Bands show up, called "isoelectric focusing." In general, the test for oligoclonal bands is a technically difficult one to run and to interpret. In a study all parts of the test are optimized, the tech is well-trained and the the technique is performed perfectly. In the real world the ability of lab techs varies, the equipment may or may not be optimal, and they may or may not have switched to the newest technique. So studies done just by looking back at the result in people's charts have not shown such a high rate of positivity.
The IgG Index is also a test that can show more immune activity in the general body over the CSF or vice versa. Neither of these tests should be interpreted as indicating that all the inflammation in the body is outside the CSF.
On top of the technical difficulties above, there are people in the field that are working to "raise the bar" to make the positive result of O-Bands "four or more." Basically this appears to be the Mayo Clinic which has huge influence in the medical community. Now, the following comments are my own opinion. I believe that influential MS researchers at the Mayo have a political agenda. This agenda is to make the diagnosis of MS more difficult to qualify for, thereby reducing the number of people on DMDs. Why this is so important, I have no clue.
Beginning several years ago, we began seeing articles by Mayo doctors that people with "Benign" MS should be watched without being given DMDs. The reasons they gave for this were several. First they maintained that a person with benign MS would continue to have a benign course and the DMD was "over-treatment" and thus, unnecessary. They also maintained that this wasted medical dollars. They also stated that someone with "mild" symptoms was likely to be non-compliant with DMDs and this was also a waste of money. And, finally, they made some argument that the side effects of a DMD were reason to be cautious, but since few serious side effects had been reported, they were a little vague about this last one.
Subsequent studies showed the Mayo stance to be foolhardy. First, studies have showed conclusively that early treatment is more efficacious than the same treatment given years later. The time to intervene in MS is as early as possible. The other finding that blew the Mayo out of the water was that about a third of people who started out with "benign" symptoms will suffer major disability along the line both with physical and/or cognitively. So, the backers of the "withhold" therapy from mild sufferers had to eat their words.
Then, all of a sudden, we start hearing that they have raised the number of O-Bands which will count as a "positive" result for the diagnosis of MS from two or more to four or more. I have yet to see any studies supporting this. I personally believe that this is just another way to get fewer people on the DMDs. I don't understand this, but their researchers have stated that they believe MS to be way over-diagnosed. That is hard to swallow when we have so many people here that were sent away from the Mayo to "live with it" who were diagnosed by someone else.
There is also a discussion of how to do a Timeline on the Health Pages:
Back to the LP: If the person shows two or more attacks of symptoms that are suggestive of demyelination and there is evidence on exam or testing that two or more different areas of the CNS have been affected AND there are brain lesions consistent with MS, then the diagnosis of MS can be made if the mimics have been ruled out. Just one brain lesion will shoot the odds skyward (to 80% or more) and two will take the odds to over 90%. The LP will support the diagnosis if it is positive (an elevated IgG Index and/or 2 or more O-Bands). If the LP is negative then the doctors don't have any further info, but it does NOT counter any of the other diagnostic findings!
Thank you for letting me rant.