Hi everyone,
I am new here, I have been reading here for a while and got much more information from this forum than from my doctors, thanks!
I am seeking desperately for a diagnosis and treatment and would appreciate any help.
I apologize for the length of my message and for English mistakes, I am not a native speaker.

I am coping with debilitating health problems for many years, it seems it might be caused by an autoimmune disorder but I don’t have any definite diagnosis.
It all started almost 20 years ago with extreme fatigue, Postural orthostatic tachycardia syndrome (POTS), dry eyes, joint pain, Adie tonic pupil and trigeminal neuralgia. A few years later I got Lymphoma and underwent a chemotherapy (which included among others Rituximab, and Prednisone). After the chemotherapy I felt much better than I felt in years, but after 1-2 years my energy gradually deteriorated up to the point that I can hardly get out of home and spend most of the time lying in bed.

I am vegan , I keep a healthy diet based on vegetables, fruits, legumes, nuts, whole-grain etc., almost no processed food and preservatives.

A few months ago I was diagnosed with SFN, skin biopsy showed severe reduction of small nerve fiber innervation, and moderate reduction of autonomic innervation. I have got numbness, tingling, burning etc., but my symptoms are mostly reduced sensation and not severe pain. Is it normal ? Is it going to progress and cause pain ? Can these symptoms give any indication for the cause of my neuropathy ?

It is assumed that I probably have an autoimmune disorder, but I don’t have any specific diagnosis.
My insurance denied IVIG because without any specific autoimmune diagnosis I don’t meet their criteria.
I had allergic reactions to Plaquenil and Imuran.
Are there any other relevant treatments ?

Tests
All tests for Sjogren, Lupus, Celiac, MS, Myasthenia were negative. Except for ANCA, ANA, Anti histone that once were positive/borderline, and later negative.
Anti gliadin was positive (the rest of the celiac panel was negtive).
No diabetes - Fasting glucose ~85mg/dl (lab range 70-100), A1C 4.5% (lab range 4-5.7).
All the routine tests are negative.

Supplements:
- When first tested I had extreme B12 deficiency 99pmol/L (lab range 180-700). I take 100mcg (cobalamin) daily and the blood levels are about 300-450pmol/L. I have read on this forum that the supplements should be stopped before the tests, I have never done it.
- My D25 level was 21.8nmol/L (lab range 5-250), I am taking 2000IU D3 daily and the level now is about 70-80.
-Other supplements: CoQ10 100mg, vit E mixed tocopherols 400IU, vit C 500mg, Calcium 600mg.

Sometimes I use Provigil for the fatigue, can’t take it often.

I read about the ACh receptor autonomic ganglionic ab test and would like to do it. I understand it is usually done as a part of the paraneoplastic antibodies panel, but since I already had my share of cancer, is it worthy to do the other tests ?

I would appreciate any suggestions regarding diagnosis, tests and treatments.
Thanks!

I had low b-12 @119 and took oral supplement plus monthly injections until my numbers got above 900. Plus if you didn't stop supplementation prior to testing, your actual numbers may lower than what is indicated. You have quite a lot going on and if you can get your b-12 above 400 you might be a little better in the fatique area. The vegan diet exposes you to this deficiency and it is surprising to me that your GP isn't aggressively addressing this. If you haven't, search b-12 deficiency and there is quite a list of symptoms. Good Luck, Ken in Texas.

Did you have a lip biopsy as part of your Sjogren's work-up? If not, you should. Keep in mind, if your testing was done AFTER receiving Rituxan and Prednisone, then results could be skewed by these drugs.

Thanks, the B12 deficiency (99pmol/L) was more than 15 years ago, it was before being vegan. I took high dosage of sublingual B12 till the blood levels were above 700. Later the levels dropped to ~200-300, I took B12 again to raise it, and it dropped again and so forth. One of the doctors recommended to constantly take low dosage 100mcg even when the B12 blood levels were in the range. Since then my B12 blood levels were usually about 300-450. The last time I checked was a year ago 467.
Is it recommended to take higher dosage in SFN ?

I understand that all of these results are probably inaccurate because I haven’t stopped the supplements. Next time I will stop supplementation prior to testing (although many doctors told me not to).

Thanks, I had a lip biopsy many years before the chemotherapy, it showed mild chronic inflammation not indicative for Sjogren. SS-A, SS-B were (and still are) negative.

I had taken Metformin(diabetes drug) for years and I guess that it blocked the b-12 absorbsion from my food. My Endo rx Foltanx that is methyl form of b-12 plus folic acid. I will take it as long as I still take Metformin. From your post it sounds like you will have to supplement always also. The common low range number is 400 so if you could get into the 900's I would hope that some symptoms would improve. Good Luck, Ken in Texas.

Thanks, I will check about higher dose of B12.