Shashi
I'm probably going to get blasted here but I am going to say it anyway, check out lyme. I had a MS dx for 6 years before I found out I have lyme. I was tested for it early on but was never told that even if you have lyme there is only a 5-10% chance it will show in spinal fluid. There are Drs who specialize in lyme and if you do some research you will see treatment can be controversal.
Several people in my family had lyme. They caught it early had a month of abx and were fine. This was what I knew about lyme. Boy was I misinformed. Lyme can be a serious neurological disease. Some MDs even think that the lyme bacteria can trigger other diseases like MS.
Just passing along my experience. Wish someone had suggested this to me, as I have many neuro problems now and my mobility is effected.
Best of luck to you.