Close to Firm Diagnosis of a Mimic - Long, but Might Help Someone?

[anotherinvisible]

I crossposted this from Limboland, because among you guys is where (as Trace420) I spent most of my forum time 2-4 years ago, and I know many of the people here are still looking for answers, as well.

Some of you know me as Trace420; I changed my account/name when I remembered 420 was a euphemism for pot and it probably looked like I was advertising recreational activities that I don't engage in (I do believe the medical use should be legalized, but that's not why I chose that string of numbers).

It's been a long time since I've been on the board, and I can very gladly say that it looks like I'm at the end of my journey to diagnosis. I hope my story helps someone.

I've known something really wrong was happening for about 13 years now. It started with extreme muscle tightness and the feeling of pulled muscles, but over the years, I also experienced parasthesias, exercise intolerance, twitching, and cramps. I experienced a lot of cognitive symptoms that I eventually figured out were just from the sheer lack of sleep I was experiencing because of pain. The disorder crept up insidiously.

The first 5 years, I didn't have health insurance - the next 6, I wasn't getting any answers - just a lot of shrugs as blood test after blood test came back negative. I finally found a WONDERFUL general practitioner a couple of years ago who wouldn't give up, and I lucked into the right neurologists after one absolute jerk basically called me a head case. (We bartered - I'd take his stupid neuropsychiatric exam and he'd give me the EMG. Guess which one was normal? Not the EMG.) The doctor administering the test said, "This is not normal and this is definitely physical." The test was nonspecific, though. That's when I was diagnosed with cramp fasciculation syndrome.

But CFS doesn't really explain a cause. There are theories, and it is definitely sometimes caused by a potassium channelopathy, but it doesn't have to be. CFS never explained, for me, the excruciating muscle tightness that put me in the most pain. Frankly, I don't care nearly as much about the fasciculations and cramps (or even the parasthesias) as I do the crazy tightness.

My neuro ordered a VGKC antibodies test, which was negative, and a myotonia workup, which showed a mutation in my SCN4A gene. These were from Athena and were expensive, but the myotonia workup provided the crucial clue. I just saw a university-level specialist who feels sure I have something called paramyotonia congenita, and I have a specialized EMG scheduled in two weeks to confirm. If it is not paramyotonia congenita, then it is definitely a disorder in the same family of SCN4A disorders.

Paramyotonia congenita is a sodium channelopathy. I've evidently had this all my life, but my symptoms were mild enough to go unnoticed as unusual until my twenties. (I do remember feeling tightness in my back even as a child, but I was very active and didn't know that the degree of it might be abnormal.) SCN4A mutations are usually inherited but can also happen spontaneously, in utero I think. No one in my family has my symptoms, but because I have the mutation and the gene is autosomal dominant, there is a 50% chance my child has the gene as well.

The specialist said that my symptoms should be manageable, which is a great relief. It is so good to know that my child, even if he has the disorder, may never have to experience it the way that I have. At the first sign there might be a problem, he can be tested for the gene and begin symptom management. The specialist also said that there are way better drugs than the ones I've tried, muscle relaxers that WILL relax my muscles and WON'T relax my brain. I'm thrilled.

I'm sorry this is so long, but I wanted to be thorough enough to strike a chord with anyone who might find this information useful. I hope everyone on this board gets their answers, and soon. [And I hope all my MS board friends are happy and doing as well as you can be.]

[Sparkysarah]

I just want to thank you for posting this. I have RRMS and it is always so interesting and helpful to learn of other rare conditions that for many of us we would not learn about wihtout someone bothering to post.

I am glad that your journey of discovery appears to be nearing an end and I hope that you can move forward now.

With best wishes and good luck

Sarah  

[anotherinvisible]

Yes. It feels really weird (but GREAT) to be at the end of such a long diagnosis hunt and at the beginning of real treatment.

The two big meds for treating this are acetazolamide (Diamox) and mexiletine (Mexitil). My specialist put me on mexiletine. The first couple of days, the temporary side effects that came with getting used to it were pretty harsh - but they seem to be abating, and I can tell that my muscles are loosening up a little bit already. I'm wondering if I should schedule a massage to hurry it along - or just to celebrate! Sigh. Bills, bills. Spa day will have to wait a long time.

[RedFlame]

So is that your definitive diagnosis?

Red

[anotherinvisible]

Yep, sodium-channel myotonia congenita, which is the same as acetazolamide-responsive myotonia, a kind of potassium-aggravated myotonia.

Best specialist ever. My EMG didn't show as many abnormalities as the one before, but he said he didn't need it to - what was happening shouldn't be. Huh. The doctor who knew the most put up the fewest hoops for me to jump through. Nice.

[anotherinvisible]

Weird, man. The dr.'s report came today. He says the suspect is "myotonia congenita," not "paramyotonia congenita." That didn't seem possible; they are caused by two different genes, and I know which gene of mine is wonky. Did a little digging, and guess what? Atypical cases of MC can sometimes be caused by my wonky gene. Huh. Some symptoms of each sound like mine, and some don't.

@summerluvr: I completely agree! One neuro once kept saying, "It can't be MS. You need to see a rheumatologist." I was left scratching my head and thinking the obvious: aren't there more neurological disorders than the one?

[summerluvr]

I think it is good to post this... doctors instead of just saying "not MS" need to also look for the rarer causes of symptoms!  I am another non MS,  rare disease person...

[anotherinvisible]

Yes, I thought of that! This isn't a dystrophy, but it is one of the many, MANY muscle diseases that now comes under the umbrella of the MDA.

The irony? When I was a kid, I LOVED watching the telethon. I always felt terribly bad for the kids and cried at the stories, but I loved the pageantry and loved feeling like I was helping when I sent my money in. Mind you, I wasn't fiscally responsible and never saved up ahead of time, so I usually only sent what I could scrape together at the last minute. I would try to stay awake all night, but I never made it.

[RedFlame]

oh, I forgot to add that you will be 'one of Jerry's kids' if you do have the disease.  Maybe they can help with any special things you might need.

Red

[RedFlame]

thank you for sharing this.  Medical students are constantly reminded that 'common diseases are common and rare diseases are rare',

I am grateful for you that you had a doctor that didn't give up.  I have learned allot on this journey, one of them being the fact that our PCP can be our best advocate when they refuse to give up.  This is excellent news for you and an end to a long battle.  I hope you continue to share your story because it will help many.  I love your 'bartering system' you came up with, really brilliant, it helped the doctor feel like he was still in control while calming his fear that you weren't really sick.

I don't think we realize how our genes really do play out in our lives.  I wish they could do an extensive gene workup at the beginning, then the doctor would have a guide to look at.  

I was sent to yet another rheumatologist (my third) recently to look in to the possibility of Sjogrens.  Unbeknownst to me he tested me for a specific gene, the HLA-B51 gene.  It is the gene the expresses Behcet's Disease.  Behcet's is another immune related disease that is progressive, the neuro part of it is also progressive.  My diagnosis hasn't changed but he is still doing some of the other tests that could confirm Behcets.  The funny part is that this gene is found in people of middle eastern descent.  

I'm hoping more will see this and add their story.  It could help many.

Red

[Lulu54]

Hi Trace/Invisible,

I had to laugh about your name change - I had not put that connection together.  :-)

What you have to say is very useful -  never give up is a great message to share.  And the other point of all the mimics that can be rare/unusual still do happen to people out there.  

We have to stay open to the possibilities - always!

good luck with this next step and I hope the meds give you the relief of your body without affecting your mind.

be well,
Lulu