Behind the Diagnosis of MS
Diagnostic Basics

First, you need to understand that Multiple Sclerosis always was, AND STILL IS, mainly a clinical diagnosis.

The definition of "Clinical Diagnosis" is:

A diagnosis that can be made on the basis of the history and the physical exam alone.

It is important that people know the difference between symptoms and signs. Symptoms are those things felt by the patient and reported to the doctor. Signs are those abnormalities on the physical exam that the doctor can objectively see and document. So only those people with observable abnormalities on the exam would qualify for a clinical diagnosis. A person who only has sensory problems and complains of numbness and tingling might not have an observable problem.

In the case of Multiple Sclerosis, the process of making the diagnosis has grown to include what is called “para-clinical” information. Para-clinical information includes imaging tests, most commonly the MRI, neuro-electrical studies like the Evoked Potentials, and lab studies like the analysis of the spinal fluid.

Finally, MS is a Diagnosis of Exclusion. This means that, before the final diagnosis of MS can be given to the patient, all better reasons for the problems the patient has MUST be excluded. There are many diseases whose symptoms, signs and lab results mimic Multiple Sclerosis. It is only good medicine to check for these other diseases before settling on a diagnosis as serious as MS. Many of the MS mimics can be treated effectively or cured so that is another reason to look hard for these.

A short history of the diagnosis of MS

The words "Multiple Sclerosis" mean "Many Scars." Before many tests were available to indicate MS, the disease was diagnosed by its characteristics. MS has a pattern--mainly the appearance and resolution of attacks of neurological symptoms, that over time, result in a person's becoming disabled. People would have more than one appearance of the disease and it always affected more than one part of, or system in, the body

The Relapsing Remitting pattern of MS was the main thing the doctors looked for. Doctors also knew that patients with this disorder often had elevated protein in their cerebrospinal fluid. And they knew that, eventually when the patient died, they would find the evidence of “multiple scars” when the brain and spinal cord were examined. They knew that transient attacks of blindness and eye pain could often be a part of MS, as could diffuse and varied abnormal sensations, balance problems, muscle weakness and spasticity. They knew of the fatigue and the intolerance to heat. In fact, a Dr. Uhthoff is famous for discovering that he could reproduce blindness in a person with MS who had optic neuritis by placing the person in a tub of hot water. This was a major diagnostic test used for MS until about three decades ago. The “Uhthoff Phenomenon" is often now referred to as the reproduction of ANY MS symptom on exposure to heat. The heat can be increased environmental heat, a fever, a hot shower or bath, or exercise.

So basically doctors had to use their own judgment in making the diagnosis. They had the patient's history, the neurologic exam, spinal tap, and the "Hot Bath test." It was an inexact science. They both diagnosed people who didn’t have MS and, obviously, missed people who did. It made little difference because there was no treatment to change the course of the disease. The milder forms of the disease often escaped diagnosis and the worst were usually diagnosed. Thus, the disease appeared to be far worse than it really was, because the world saw mainly the most disabled with the diagnosis of MS. Its reputation was that of a death sentence and it was feared like leprosy!

In 1965 the first attempt was made to provide doctors with a structure in making the diagnosis of MS. This was called the Schumacher Criteria, and it was actually very simple. The patient needed to have evidence of what was called dissemination (or spread) of the disease BOTH in time (6 months or more) and in space (different body parts). Subsequent attacks had to involve different parts of the body. This simply meant evidence of more than one attack and indication (signs on exam) that the brain or spine had to have been injured in more than one place with at least two of the injuries happening at different times. This requirement for definite diagnosis of Relapsing Remitting MS remains today.

There were other criteria. One was an age range (now abandoned) of the disease occurring between 10 and 50 years. Another was objective neurologic findings on physical exam. These two criteria were looser. One could substitute for the other.

The final criterion is one that has continued to the present time. It is very important! I mentioned it earlier. There must be no better or more reasonable explanation for the patient's symptoms and problems. This makes the diagnosis of Multiple Sclerosis also a DIAGNOSIS OF EXCLUSION. You have to exclude other possible, reasonable causes for the patient’s symptoms and findings. This is done mainly by the use of blood tests. Examples of diseases that mimic MS are syphilis, B12 deficiency, lupus, other autoimmune diseases, HIV, other brain infections, and disorders that make the patient susceptible to strokes, such as blood that clots too easily.

By 1983, there had been a great explosion in the capability to use laboratory tests and imaging techniques to diagnose neurological diseases. The Poser Criteria of 1983 kept the original requirement of Disease Dissemination in Time and Space, but allowed for the use of the newly available tests to document new CNS lesions that might not have expressed themselves in symptoms. The age range was thrown out as testing was proving that MS can occur at younger and MUCH older ages. Currently the disease has been documented as early as 18 months of age and beginning as late as age 71. (upper age edited)

Some of these tests that were now available were:

CSF protein, CSF IgG (antibody) studies and Oligoclonal Banding (also an antibody test)
CT scans
MRI and other neuroimaging (in its infancy)
Evoked Potentials testing of eyes, ears, and sensory nerves of the body

The Poser Criteria categorized Multiple Sclerosis into four categories that we still hear today - on the forums and from neurologists who have not kept up with current thinking and research- but this usage is outdated. The Poser categories of MS were: Clinically Definite, Clinically Probable, Laboratory-Supported Clinically Definite, and Laboratory-Supported Clinically Probable. These criteria were good for research purposes, but were not for determining prognosis, they gave no help in advising patients about what lay before them. And over the next several years doctors found the Poser rules had other problems. There was no agreement on exactly how to interpret the MRI’s, and there was no way to use the MRIs to diagnose Primary Progressive Multiple Sclerosis.

In 2001 and international panel of experts formulated the basis of the rules we use today, the McDonald Criteria. These changed the categories of MS diagnosis to "Definite MS", "Probable MS." and "Not MS." After these rules were in use for a few years, the McDonald Criteria were found to be useful, but many neurologists felt they were unnecessarily rigid in the "counting" of MRI lesions. It had become clear also that spinal lesions were much more important than previously thought. At the same time, there had been a change in medical science's ability to treat MS, with the development of the Disease Modifying Drugs (DMDs).

Also, evidence was becoming conclusive that very early treatment of people of people who were likely to have was the most effective in the earliest stages of MS. The goal, of course, was to slow the progression of the disease, or even to delay its "definite" appearance. In 2005 the Revised McDonald Criteria were agreed upon, and these are what are used today to guide the diagnosis of MS. The revised guidelines are simpler and allow for the early treatment of people who are "highly likely" to have MS or to develop it in the near future, but who do not completely fulfill the 2005 Criteria. These are people who have had one clear attack and other positive findings on testing - a situation called "Clinically Isolated Syndrome" or CIS.

The McDonald Criteria, both original and revised, acknowledged the possibility of diagnosing MS on the basis of the patient's history and physical exam alone. Again, this was further acknowledgment that the diagnosis of MS can be solely a clinical one. It also acknowledges that the information in the History and Neurological Exam are of critical importance.

An example of how the diagnosis of MS "could" be made without an MRI or other testing might be like this: A person has an attack of eye pain and loss of some vision. The attack lasts maybe a couple of weeks and the eye doctor sees signs of Optic Neuritis (ON) when they look in the patients eye. The person sees a neurologist and, apart from the visual problem the neuro exam is normal. Gradually the vision and the eye pain return to normal.

Six months later, the person suddenly begins having problems over a couple days with weakness in the right leg. The neurologist does a neuro exam. On this exam the patient now has markedly hyperactive reflexes at the R knee and R ankle. His reflexes were normal on the first exam. Hyperactive reflexes indicate spinal cord disease. The neurologist runs all the blood tests for other possible causes of the Optic Neuritis and for the weakness and hyperreflexia, and those tests are normal.

Based on two factors---the first attack, which had a positive physical finding of inflammation of the optic nerve which ultimately improved or "remitted," and a second attack, showing the objective finding of pathologically increased reflexes indicating a lesion in another place--the neurologist is able to make a firm diagnosis of MS, once all other reasonable possibilities have been ruled out.

In reality, this scenario would rarely happen in developed countries without ordering an MRI to use as a baseline. According the guidelines of diagnosis, this MRI would not have to be positive in order for the neurologist to be confident the person has MS. However, it takes a smart and very confident neurologist, usually an MS Specialist, to diagnose MS with a normal MRI. It does happen, though.

Sometimes the diagnosis is really this easy. Many times it is not.

Quixotic1

Addendum: The text in red is my addition and explanation. I think it helps describe the topic, but I am interested in what you guys think also.

Quix, thanks for this information. Most of it I already knew but there was some I didn't.

I am one of those that recieved a clinical diagnosis. In 1986 there were 2 MRI machines in the entire state of Colorado. The brain MRI was clear and at the time I did not have a MRI of the c-spine because it wasn't known what if anything a MRI would show of in the spine.

My blood work was good, VEP was inconclusive, Myelogram came out fine and the LP was positive.

I was in the middle of a severe exacerbation and my neuro exam reflected that.

Thanks, Quix. Good outline!

Did I read that right--that MS can BEGIN as late as age 78?

I know that MS is sometimes diagnosed in the 50s, 60s, or even 70s, but do they really believe that the disease can BEGIN that late?

Just curious. (I was 42 when my "there's something wrong" symptoms began, but I had some unexplained dizziness and other stuff going back to age 26.)

Nancy T.

Hmmm.....maybe I did mix up two pieces of data. I know they have found cases where it has begun in the 60's and 70's and maybe the 78 is the oldest diagnosed. I'm not sure. I'm also not sure it matters. Every year the upper age "found " (a little vague) goes up. There is no reason to believe there is a TRUE and absolute upper age, but if you think I should edit it indicating all this, I can do it with another color.

My symptoms began at age 53. This I know for a fact. Yet the old wisdom was that it never appeared after age 50.

I think the point is mute (uhhh...shall we say moot?) Sheesh! Of all the things I have lost, I miss my braion the most.
Quix

Okay, I found one of my favorite references on the topic and in this study the oldest age at presentation of symptoms was 71. I will amend my first post in a different color. Sorry. But, the point does remain that it can be seen to present with symptoms after age 70. Here is the reference:

http://www.docguide.com/news/content...2571FA00692EDE

Nancy, we have to distinguish between the first onset of symptoms and the beginning of the disease. We all know that the disease can begin without symptoms and that the symptoms may not appear for some years. I don't know if the experts can put any timeline on when the damage to the CNS actually begins. It would depend on whether the first lesions "spoke up" with symptoms. So my statement in my post is when the disease "presented." this last comment was added a little later.

Quix

Excellent Info, Quix..thank you.

Awesome.

Cherie

Makes sense... they say that some people have MS lesions found at autopsy when they never had symptoms during their lifetime, so it would make sense that someone could have had MS a long time ("the beginning of the disease", as you put it) but not had "first onset of symptoms" til very late in life.

You've sure put a lot of work into this, Quix. As they say, writing is 1 percent inspiration and 99 percent perspiration--something like that!

Nancy

Very fascinating. I knew that a purely clinical dx was possible, but hadn't really thought it through as thoroughly as you did with your possible scenario.