low c3/c4 typically indicates that something is "consuming" the compliment. Usually a compliment mediated inflammatory process. It can be lupus, but thats not the only thing that can do it.
For some background, compliment is called into action by b cells and a little sentinel called c1q (that goes around pinging antibodies lookin for a fight), to remove pathogens, but it can also be high-jacked by an autoimmune process.
In lyme and mold c3a and c4a normally go up. C3 and C4, I think, go down. I've tried to verify this by asking a neurologist, but they dont know the correlation of C4 to C4a. No one knows, its amazing. These people dont understand their own tests, it aggravates me to no end.
So I've tried to piece it together, and the best explanation from looking at papers w/ data on diseases that I can piece together, is that C3 and C4 go down, and C3a and C4a often go up (C4 is cleaved into C4a when its consumed). So you are talkin about
two slightly different markers. Have your c4a checked. In lyme and mold it should be high, 4,000 - 10,000 i think.
What are your symptoms?
Post Edited (dcd2103) : 7/19/2021 9:10:35 AM (GMT-6)