Welcome to NT! There are many disease and conditions, including vitamin and mineral deficiencies, that can mimic MS. It's a process of ruling out all other possibilities and a collection of symptoms, clinical findings, and tests.

Lhermitte's sign (BTW - there is no hyphen between the L and h in Lhermitte's) is common in MS as well as other neurologically based diseases/conditions. It can also happen with vitamin B12 deficiency.

I am glad your doctor is being proactive and helping you find a cause for your symptoms. The MRI results and LP will help in the diagnosing process. I was dx based on clinical symptoms as well as MRI. I have not had an LP done. Each MS case presents differently, yet there are common signs and symptoms we share.

Hang in there and check in and let us know how you are doing and the results.