MS symptoms can be vague, and many other neurological problems can have similar symptoms, even scans cannot always tell.
[link removed] will give you some idea of how many other diseases show similarities.
First I was diagnosed with MG (left eye and face drooping; extreme weakness in legs and arms; I can't look up at all; double vision to the left and right and when looking up; bad balance problems; choking; weakness in voice). Tests came back negative. Now symptoms are extremely worse. Extreme pins & needle feelings in arms, legs, feet, across the back, across the stomach, across the chest and the buttocks. I can barely walk, with a schuffling; It's extremely difficult to get up and down out of a chair or climbing steps; the weakness has gotten extremely worse; Pins & needles worse; lost feeling in feet and parts of legs (I burnt my left knee on a heater and didn't even feel it); my right heel around the edges of the heel is extremely painful and increase when I'm on my feet a lot. It keeps me from sleeping; it doesn't stop when I'm off of my feet or have my legs up on the couch and I get sharp blairing pains that shoot up; I feel short of breath or my breathing is labored. My blood work and spinal tap also came back normal. My neurologist advised that she feels it's MS. I am going to have another MRI with a MRA this coming Mon. as there were some spots on the last MRI 10/08 but nothing really definite. I've had blood work, CT head, MRI head, cervical and lumbar (I have 1 bulging disc in cervical & lumbar with stenosis). This has been going on since May 08 and I'm just so frustrated. Please advise if there are other diseases that mimic MS. Thanks so much.