Unfortunately, I didn’t order a c3 test and am regretting it now.
Attached is a picture of the results of the blood work I ordered. Caught my platelets at a good level fortunately (they usually float between 100k and 150k when my lymphocytes are up.
My question is directed to my low complement c4 level. This post may be similar to my last post (thank you all for your thoughts!)
I also tested my ANA IFA again and this time it was negative. I was doing some reading on this test and don’t think it’s very sensitive in comparison to newer stuff that’s out there.
Would like to here your thoughts about the c4 complement.
Previously:
1/24/19 c4 complement was 18
range: 19-52 Mg/dl
6/13/19 c4 complement was 16
range:14-39 mg/dl
6/17/2020 c4 complement was 12 Low
Range: 14-44 mg/dl
Thanks!
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JennaShi
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C4 can be low in a lot of chronic inflammatory diseases. Low C3 is more specific for CTD inflammation due to its specific function within the immune system particularly when looking for lupus nephritis. When you have inflammation, both c3 and c4 are consumed unnecessarily and can be low. The low MCHC is borderline low but meaningless since your MCV is on the higher end. Have you ever had your iron, B12 and folate levels checked? Thyroid labs ever? These can causes your cells to widen due to decondensed DNA secondary to nutritional deficiencies. Vit D would also be a good one to check.
My c3 and c4 are chronically borderline low. They dip really low when I flare. Low c3 is actually a lab criteria used in diagnosis of lupus or lupus like illnesses.
That makes sense with the c3. When you flare, do other things show up/ do they test you for other stuff too?
I have been tested for Iron, b12 and vD bt not recently. My iron and b12 are tested because I have autoimmune Gastritis. I inject with b12 and the level was last over range. VD is a constant low but not terrible. Thyroid levels are perfect according to my endocrinologist as I have been completely hypo and dependent on medication.
Haven’t had that one tested in a while but will ask thank you. Is there any further testing that either of you would recommend? I will he seeing my primary tomorrow morning. I saw something today called ch50 or 150 i think it was for testing all the complements but am just unsure.
Yes low C4 is used as one of the key markers to help in diagnosing lupus (it’s on the SLICC and BSR criteria). It doesn’t mean you definitely have lupus if you’re still in diagnostic uncertainly stage, but added to symptoms, is certainly another important puzzle piece - and some drs seem to need blood evidence too.
Yes you’re right the total complement is measured by CH100 or CH50. This is the key test for me as it gets severely reduced when I’m flaring but is normal when I’m ok. Sometimes your C3 and C4 might not drop much or at all but they, or other parts (often C1q in lupus or C2) of the complement proteins may be present but not working.
It’s a bit confused by the fact that some people with lupus will have been born with a part of this complement system missing/ partially missing (Often a bit of the C4), which will have made developing lupus more likely, so the only way they know is if the complement is ever normal at times. But either way a low total complement, C3 (although C3 changes in a lot of diseases) and/ or C4 are clear evidence of immune dysfunction.
If you’ve been positive once for ANA that is sufficient for classification and some people’s changes between positive and negative completely unrelated to how active the lupus is (it can depend on treatment, time with disease and just be fairly random). Some rheumys haven’t got up with this research yet and keep measuring it and then tell people they can’t have lupus if their ANA has gone negative. This is not correct and the more knowledgeable rheumys are trying to change that attitude but some rheumys (and certain some other specialists) seem loathe to consider and treat lupus without permanently positive ANA- and don’t look at other markers.
There are loads more blood tests you could have. Things like clotting levels and iron levels can show inflammation too.
Thank you Melba1 for taking to the time to share this information with me. There is so much to learn! I’m hoping someone in the near future will be able to confirm or rule out Lupus with more testing and putting together the new information with the old.
CH50 measures total complement activity and is usually low as well in inflammation. Lupus is also associated with C1q deficiency which can cause a paradoxical elevation in C3 and C4 since complement pathway doesn’t function normally.
I have attached a paper that reviews complement ranges in lupus.
With regard to other testing, I’d leave that up to your provider since most testing is based on clinical picture such as symptoms, progression, functionality. I hope this helps and I hope your appt goes well today! ❤️
Jenna - the important thing is the total of your clinical picture and lab results. It isn’t that doctors don’t care about the labs, but they first look at the constellation of symptoms, then run the appropriate labs. You might want to make an appointment with your doctor to go over everything with you.
One of our members had a great strategy. She advised a member to ask what convinced the doctor that she did not have a particular disease. That allows the doctor to full explain their reasoning.
Thank you, I will. That’s a great idea that she had, I hope it helped. With the last results I shared (specific genes and this c4) I think will help as this is new information.
I have some good news. I took your advice and asked my primary this morning and she told me she was in no position to decide whether i had lupus or not because she isn’t a professional on the matter. She took me very seriously and is giving me a referral to UCLA for rheumatology and have one for neurology for my polyneuropathy. She has always been so kind. I hope that they will be able to figure it all out as a team.
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Blood test results: investigation Lupus/Mixed Connective Tissue Disease 
Is this permanent?
Has anyone had a similar journey?
