Devics disease

My cousin was dx 20yrs ago with MS when she was 16 after developing ON. Since then she has slight walking problems. Recently she was told after an LP (after her own insistance) she hasn`t got MS but has Devics Disease. The simalarities between the two diseases are uncanny but to be told 20yrs down the line its something else is hard to get your head round. I was dx with MS 4yrs ago and up until recently thought my cousin was the same as me due to the obvious genetic factor. Now it makes me wonder...


Hi Steve,

Devic's disease is a demyelinating illness closely related to MS, and may or may not be a 'subtype', so I don't think the similarities are coincidence, or "uncanny".

For some reason, Devic's attacks primarily the spinal cord and optic nerve, and the brain is lesser affected, whereas MS is not so picky.

It's interesting that there should be a case of Devic's, and one of MS, within the same family.  This might be random, or might suggest there are shared genetic factors - just as you believed when you thought you both had MS.

It might be worth mentioning to your neuro that someone else in the family has Devic's.  Not because I'd expect them to do anything about it, particularly, but they might at least find it "interesting".

I've got another known case of MS in the family (but not Devic's) and did mention it to my neuro, who can't have thought it was a complete red herring, as he wrote it down.


Thanks for your relpy Tina, from my understanding Devics its unrelated to MS in the sense that its not hereditary. My cousin fitted the jigsaw since I was dx up until recently, then this has thrown a different ball in the park in my way of thinking.

Reading into Devics disease has given me a different view on MS eg. the way more asians have it rather than us westerners. They seem to get misdiagnosed with the label  MS when it should be Devics .The complete opposite of myself. Devics is more rare than MS, it makes me wonder how many other MS`s out there have beeen wrongly dx and received the wrong treatment.



Hi again, Steve,

MS is not hereditary either, so I don't think that's the key distinction between MS and Devic's.

There's definitely a genetic aspect to MS, but that still doesn't mean it's inherited.

Certain combinations of genes (and it's known to be many, not just one) may make a person more susceptible, but they are still not guaranteed to get MS, even if they have the "high risk" genes.

So it's not a case of simple heredity.  About 1 in 5 MSers have a known other case in the family.  Which means 4 in 5 don't!

The very fact some races are disproportionately affected means Devic's, too, must have some genetic component, without being hereditary.  If it had nothing at all to do with genetics, all races should be affected equally.

Although Devic's disease and MS can present similarly, I would have thought misdiagnosis was very rare these days, due to ever-improving imaging techniques.  An experienced neuro should easily be able to tell the difference, since Devic's does not produce the classic brain lesions of MS.  I'm guessing that 20 years have seen big changes in the quality of images, so when your cousin was diagnosed, 20 years ago, it would have been more difficult.


Hi Steve, there is a blood test to help diagnose Devics. Devics or Neuromyelitis Optica is what Dr's are looking for in me after fourteen years in and out of limbo.

With Devics the relapses tend to be more severe than with MS and they leave more permanant disability. If your cousin has had Devics for twenty years and has slight walking problems she's doing well. Some people do show brain lesions on MRI aswell.

More people are being diagnosed with Devics sooner now with the NMO-IgG blood test. Has your cousin had this blood test?

MRI images of the spinal cord in Devics tend to show more extensive myelitis then MS does.

Jacqui x

Hi Steve,


You are spot on when you wonder how many people out there with an MS dx actually have NMO/Devic's. The latest version of the McDonald criteria specify how to differentiate NMO from MS (google Polman et al, 2004, Diagnostic Criteria for Multiple Sclerosis: 2010 Revisions to the McDonald Criteria - the second page, half way down the first column). If they are taking the trouble to put this in a paper about MS, then I think we can safely conclude that some neuros are still getting it wrong!


Karen x