I was told I had ‘probable MS’ at my first neuro appointment. The consultant asked me first when I went into the consulting room if I was the kind of person who wanted to know what was wrong, if anything, or if I would rather live in ignorant bliss. I said I wanted to know.
She then did various reflex tests and so-on, and she at that point said it was probable MS (I had slower reactions on my right side), but she wanted to order an MRI and further blood tests to confirm. One had already been done by Ophthalmology (due to me having optic neuritis) and they’d requested full brain and optic nerves. She looked at the scans while I was there and could see there were 7 or 8 lesions on my brain (Radiology hadn’t done the report at this stage), and instantly told me she would refer me to the MS nurse. She also ordered extra blood tests to rule out things like lupus, and to see what my calcium and vitamin D levels were. I am waiting for an appointment with the MS nurse (don’t know how long that’ll take, but I’ve been waiting 3 weeks) and a letter to confirm if I should take vitamin D supplements as well. I went to my GP today, and he read the MRI report which confirmed lesions in my brain consistent with MS.
So, long story short, I would say yes you can be diagnosed with probable MS at your first appointment, but it may well depend on what information the Neuro has about you when you go in.