Yes, I tested positive for it (but not for the N-type) on the Mayo Paraneoplastic (PAVAL) panel, which Dr. Systrom ordered for me back in February as a screen for neurological autoimmunity. The P/Q-type CC autoantibody was the only positive one (at .04, normal is <.02) from the panel.
Thank you so much for your detailed reply
@ChloeC and your PM. I initially learned that I was positive for the N-type Calcium Channel Autoantibody on the PAVAL Panel from Mayo in 2016. I was positive at .05 and later when re-tested on the DYS1 Panel (also Mayo), I was positive at .06. I was negative both times for the P/Q calcium autoantibody. I am so thrilled to learn that more doctors are now testing for autoimmune causes of neuromuscular issues and of dysautonomia.
Dr. Systrom referred me to Dr. Khosro Farhad because of it, but I didnt get in to see him until 2 weeks ago-- which is super frustrating, cause it sounds like there is a specific LEMS drug I can likely benefit from, which would have been nice to be on the last 8 months!
I am not familiar with Dr. Farhad and will definitely Google him. I am sorry that it took eight months to get an appt. I had tried to get a consult with a different doctor who worked with these autoantibodies but she was closed with a 2.5 year waiting list at the time! But she was very kind to reply to my e-mails and was very helpful.
I tried to get Dr. Farhad to order the CellTrend tests or any other neuromuscular/dysautonomia autoantibodies there might be out there that weren't on the PAVAL panel, but he gave me a line I hate hearing from doctors: "What's the point of doing more testing if it won't affect your treatment?"
You can order the Cell Trend tests on your own as long as any doctor just signs the form approving the blood draw (although this may vary from state to state). My main doctor found the Cell Trend results to be helpful in my case b/c I tested positive for 7 out of 9 autoantibodies and we ran the test twice (prior to starting treatment). I also tested positive (on Mayo Panel) for anti GAD65.
My doctor ultimately felt the same as yours though and we stopped testing for autoantibodies once I had eleven of them! He said that even if I had more (which he assumed that I did), it would not have changed the course of my treatment plan which was high dose IVIG and then Rituximab.
His point being that the positive CC antibody is enough of a rationale for insurance and of a medical indication for starting IVIG (or really SCIG i think?), which would also treat any other autoantibodies I may or may not have.
I agree that for insurance purposes, if you are trying to get IVIG, they will accept the LEMS diagnosis (although they may still try everything in their power to deny you b/c IVIG is such an expensive treatment). IVIG will work on autoantibodies even if they are not specifically labeled yet (so even if you are positive for the Cell Trend Abs, the treatment will still help prior to you knowing). I hope that makes sense!
But, um, Id like to know what is going on with my body! Especially since the IVIG is a second-line treatment to start if the LEMS drug (3,4-dap) doesnt help enough, whereas if I knew I had other autoantibodies that have no drug treatment available, Id push to start the IVIG right away.
That is interesting that he was going to start you on 3,4-dap and I assume this means that he feels that you have a definitive LEMS diagnosis? Is he basing it solely on the P/Q autoantibody, or on an EMG & nerve conduction study, or on clinical symptoms/criteria? The gold standard is the "single fiber EMG" (which I did not have and wish that I did back in 2016).
When I sent you the info via PM re: the N-type Calcium Channel Ab group, I should have also sent you the info on a LEMS group that I also participate in. Many of the members of that group are on 3,4-dap or Firdapse. But others are on Mestinon, IVIG, Rituximab, etc. There is a lot of variation and they would be able to give you a lot of good feedback.
Not to mention baseline numbers are helpful to evaluste the success of treatment, knowing a certain symptom is due to a certain cause means you can stop going down all the other rabbit holes, etc.
Does this mean that you feel your diagnosis is LEMS vs. ME/CFS? I had been given a diagnosis of "CFS" by 5-6 doctors in 2013 and 2014 and it was not until I tested positive for the calcium autoantibody in 2016 that my doctor started to really re-think if I had the correct diagnosis. Some neuros feel that you must have the P/Q Ab in order to be given a LEMS diagnosis but others feel that the N-type Ab is equally sufficient. There is also sero-negative LEMS.
I also have muscle weakness and coordination issues that started out mild but have progressed significantly over the past year or so. You can read about the rest of my symptoms in my intro post:
https://forums.phoenixrising.me/threads/still-processing-in-boston-and-nyc-former-lurker.75698/
Thank you for linking to that and I missed your intro post when you originally wrote it. I skimmed through it last night but am planning to read it in more detail. What is your muscle weakness like? Does it affect your breathing (lungs and diaphragm strength)?
My understanding from the appointment was that he wants to start the LEMS drug 3,4-dap first and see how that goes.
That is interesting and he must feel fairly certain that LEMS is your diagnosis.
Im eager to start it, but need to do a repetitive nerve stimulation test and brain MRI first to establish a pre-treatment baseline, and its proving absurdly difficult to just figure out how to schedule those.
Will you be having a high resolution lung cat scan to rule out small cell lung cancer (SCLC) in case you have the P/Q Ab as part of a paraneoplastic syndrome or cancer? These calcium Abs often link to lung cancer or LEMS but I don't want to sound alarmist and they are also often due to random autoimmunity and no cancer is ever found (like in my case). I have done three lung cat scans and no cancer was ever found.
In Feb, it will be four years since we discovered I had the Calcium Ab (and I may have had it longer but just did not know b/c I hadn't been tested for it prior to 2016). Some studies say to have the lung cat scans for five years but my main doctor did not think it was necessary in my case and that three years was adequate (and it is a lot of radiation). I also do regular mammograms and pap smears and recently did a colonoscopy (but the link is to lung cancer).
Also, if you can and it is not too late, I would request the single fiber EMG which is the gold standard test.
and now both the NH and MGH offices are telling me only the other one can help me, sigh.
That is so frustrating and I hope you can get this straightened out