What tests do I need?

Question:
Thank you for reading my short medical history below. I am looking for advise on MS. I am a man - age 62. In August-2014 my MRI was clear (no lesions) but the MRI for my spinal cord showed two lesions. One lesion 1,2 cm long in Th9 vertebra, and one lesion in C2 vertebra. Oligoclonal bands (OCBs) were found in the cerebrospinal fluid (Oct-2014). No changes in both spinal cord and brain MRIs (6 months later – Feb-2015). A test on anti-AQP4 antibodies was negative.

My neurologist's opinion is that I have MS but without clear diagnosis (PPMS, PRMS etc). I have started therapy with 20 mg Copaxone injections as of Jan-2015 (3 times per week), following my neurologist advise.

Clinical condition: Walking difficulties as of September 2014, fatigue and sometimes sleepy for some seconds (watching TV). Very often numbness on left hand. Left foot slight drop after walking for 1Km distance. The foot drop symptom after long walking (more than one Kilometer) was present even 3-4 years ago. I have never had any visual disturbance (diplopia) or relapse experience up to now. Testing of VEP (Visual Evoked Potential) in June 2015 showed a slight signal delay (0.3 degrees) in both eyes. I am not sure its a NMO indication. but the doctor who made the VEP exam told me it is possibly not.

I would appreciate your advise on the following questions:

Do I have to do more medical tests or another MRI (one year after the first one) is enough?

I am not sure I am following the right medication treatment since Copaxone is provided to patients with specific MS category and I do not have any clear MS category diagnosis yet. Thanks in advance for your help.

Answer:
This diagnosis of MS is a clinical one (no one test can definitively render a diagnosis), which can lead to some ambiguous cases from time to time.  A critical component for a diagnosis is that reasonable alternative diagnoses (i.e., mimickers) have been ruled out.  The AQP4 antibody was a reasonable test, and is typically run on the blood (however, there are cases where the blood test is negative, but he spinal fluid test is positive).  Other things that likely require consideration is for your physician to check a vitamin B12 level (with homocysteine and methylmalonic acid), HIV, ANA, SS-A/B, ACE, and a copper level.  I suspect that some (or all) of these may have been checked as well.  Based on the other results of your spinal fluid and your clinical presentation, your neurologist may have looked into causes of myelitis (inflammation of the spinal cord which can be confused with MS).   Whenever I come across a possible MS diagnosis (but the brain MRI is completely normal), I think it is very important to screen for mimickers as MS nearly always affects the brain.  With that said, individuals with PPMS tend to have very little evidence (but some) on the brain scan with more notable findings on spinal cord imaging.

Copaxone is probably the safest medication we have for MS, so if your neurologist feels confident that he/she has ruled out reasonable mimicking diagnoses, then that may be a reasonable approach to treatment.  Keep in mind that the disease modifying therapies are all 1) partially effective, and 2) take time to exert a beneficial effect on the inflammatory changes of MS.  In the case of Copaxone, it may take a little while longer to take hold.  As you just started this medication 5 months ago, I would advise patience at this point, and discuss with your neurologist appropriate goals for the therapy.

A. Scott Nielsen, MD MMSc
Virginia Mason Multiple Sclerosis Center