Blood tests - ANA positive, high IgM, borderline low C3

[ShonaGreen]

Hi, I have a Rheumatology appointment soon following a bad case of chilblains which I've had for nearly 2 months on my toes and heels, now ending up with brown think skin developing on some toes which the GP thought looked necrotic at the time, and all toes are usually purple/black looking now. I take Nifedipine but it doesn't help.

I've had a lot of blood tests, positive for ANA 1:160 homogenous & cytoplasmic pattern, also high IgM and borderline low C3 with 1.03 (range 0.90-1.80) but negative for Dsdna and ENA. I'm still waiting for results of APS and cryoglobulin.

I developed Raynauds when I was about 40 (now 48) and since then also have hypothyroidism, chronic migraines and POTS (not symptomatic thankfully). I'm very active and was a keen runner until developed knee arthritis recently, but still do swimming etc.

Had first visit to Rheumatology 3 years ago due to bad chilblains on fingers during spring, also lasted for 2 months. Apart form ANA 1:320 all other tests were OK and i was discharged.

I'm concerned that I'll quickly be discharged from Rheumatology again due to most tests being negative. I feel like things have ramped up with the Raynauds and chilblains as very painful, swollen and lasting for months and in general feel very low energy.

Just wondered if anyone in a similar situation and has any thoughts, thanks in advance!

[OldTed60]

Hi. I can understand your concerns about lack of ENA antibodies and it may.be that you get a diagnosis of UCTD (undifferentiated). However you only mention them screening for Lupus and APS - not Sjogren’s or Scleroderma, Myositis or Vasculitis or even MCTD? How extensive were the immunology tests ordered do you know? This is important.because It’s relatively easy for them to rule out seropositive RA, Lupus and Sjogren’s but much less so with the others. Systemic Sclerosis is extremely heterogeneous and there are actually 13 known antibodies so all would need testing using multiple lab screens before they can even exclude it by about 90%.

[ShonaGreen in reply to OldTed60]

Hi OldTed60 thanks for your response. These are the tests Rheumatology requested,

‘scleroderma screen', 'ENA immunoblot, 'antiphospholipid antibodies', immunoglobulin and C3/C4. Ideally 'cryoglobulin' too.

I guessed that as the ENA was negative they wouldn’t do further tests to explore Sjorgens or Scleroderma. ANCA was done few years ago and was negative.

From reading everyone’s posts I appreciate it can take years to get a diagnosis so just want to make sure that I make the best of my Rheumatology appointment. Attached picture when toes were at their worst, the brown one has got better but that big toe has about 5 chilblains on it now, along with lots on my other foot. Least the weather is getting warmer which should help!

Brown toe

[OldTed60 in reply to ShonaGreen]

Hugs - that does look very painful. Hope they don’t become ulcers 🤞🏻. 30% of Sjogren’s people are seronegative - I am! I had to have a lip biopsy to confirm although I do also have high immunoglobulins - usually associated with seropositive Sjogren’s I’m told. My Scleroderma antibody is called Fibrillarin / U3 RNP - which is most reliable if picked up on the Elia / Immunoblot panel. Apparently it is associated with the nucleolar ANA pattern and highly specific. Most SSc patients only carry one strongly positive antibody and this is mine. But it’s only found in 4% of SSc patients so this is why I made the point that it’s important that your hospital can test for rarer antibodies if the usual ones don’t show up. It took me 12 years from onset and a trip from Scotland to London’s Royal Free to get unequivocally diagnosed. Best of luck to you. Let us know how it goes x

[ShonaGreen in reply to OldTed60]

Hi OldTed60 that’s really helpful info thanks so much, I’ll look into the antibodies you mentioned as haven’t heard of them before.

[OldTed60 in reply to ShonaGreen]

Also worth looking up the anti Th/ To antibody which is part of same panel. This one has shown up previously for me as a weak positive but the U3 RNP is always high so this is my antibody.