About 5% of people with MS don’t have lesions in the brain. The MS Society lists conditions to rule out in order to confirm the diagnosis of MS (on the link below). I had many or your symptoms myself due to vitamin B12 malabsorption due to autoimmune pernicious anaemia.
http://www.nationalmssociety.org/Symptoms-Diagnosis/Other-Conditions-to-Rule-Out
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"B12 deficiency: a silent epidemic with serious consequences" by Chris Kresser..
"Why is B12 deficiency so under-diagnosed?
B12 deficiency is often missed for two reasons. First, it’s not routinely tested by most physicians. Second, the low end of the laboratory reference range is too low. This is why most studies underestimate true levels of deficiency. Many B12 deficient people have so-called “normal” levels of B12.
Yet it is well-established in the scientific literature that people with B12 levels between 200 pg/mL and 350 pg/mL – levels considered “normal” in the U.S. – have clear B12 deficiency symptoms. Experts who specialize in the diagnosis and treatment of B12 deficiency, like Sally Pacholok R.N. and Jeffery Stewart D.O., suggest treating all patients that are symptomatic and have B12 levels less than 450 pg/mL. They also recommend treating patients with normal B12, but elevated urinary methylmalonic acid (MMA), homocysteine and/or holotranscobalamin (other markers of B12 deficiency).
In Japan and Europe, the lower limit for B12 is between 500-550 pg/mL, the level associated with psychological and behavioral manifestations such as cognitive decline, dementia and memory loss. Some experts have speculated that the acceptance of higher levels as normal in Japan and the willingness to treat levels considered “normal” in the U.S. explain the low rates of Alzheimer’s and dementia in that country."