What all can mimic multiple sclerosis?

Many conditions. Initially the ms patient goes through many diagnostic considerations. Stroke, drug effects, malingering, viruses, toxic reactions, lupus, pinched nerves, are just some of the common initial concerns. It may take hundreds of tests and repeated bouts before a definite diagnosis can be made.
All of below. CADASIL. lupus or other arteritis/vasculitis, anti-phospholipid antibody syndrome, Sjogren's, Lyme disease, HIV, syphilis, B-12 deficiency, meningeal carcinomatosis, to name the more common differential diagnostic thought.

Related Questions

What disease might mimic multiple sclerosis?

Several potentials. Cadasil, lupus, arteritis, clippers, pernicious anemia, cervical spondylosis, lyme disease, CNS lymphoma, sjogren's, melas. If you get the point, ms may be hard to diagnose, and often need to exclude other explanations. Patterns may or may not be different, and sometimes it is important to get testing and even several opinions. Read more...
Many. As dr. Mechanic said, there are mimics. Please see his answer for these. One thing he did not mention, is atypical migraines. Read more...

Which others conditions can mimic the symptoms of Multiple Sclerosis?

Lyme Disease/Mercury. A common condition that mimics MS is Lyme Disease. Many doctors who are knowledgeable about Lyme feel about half of those diagnosed with MS actually have Lyme. It's important to rule out Lyme, as Lyme is more readily treated than MS & MS treatments can worsen Lyme. See http://tinyurl.com/pzredho For an even more radical perspective see http://tinyurl.com/9kz8hwy Also consider mercury toxicitity. Read more...
MS mimickers. Stroke, vasculitis, systemic lupus, antiphospholpid antibody syndrome, neuromyelitis optica, transverse myelitis, myelopathy, metastatic or multifocal neoplastic disease, complicated migraine, ADEM to name a few. Read more...
Numerous. But usual suspects include lupus, Lyme disease, Neuromyelitis Optica, B-12 deficiency, antiphospholipid antibody syndrome, Sjogren's, CADASIL, arteritis/ vasculitis, carcinomatous meningitis, HIV, syphilis. Read more...