My dd5 has been struggling with her health following an infection that triggered a variety of autoimmune responses.

In June of this year, she started with cyanotic episodes (no loss of consciousness), abdominal pain, loss of weight, and liver/kidney issues when she gets sick with things like a head cold.

2 years of her body doing goofy things, and docs have run blood labs galore. Her ANA, RF, and other anti body tests have come back negative. Randomly, a c3 and c4 were drawn in her last flare, and they were both almost at zero. They redid when she was well 3 weeks later, and they came back slightly higher than normal range.

She has had lots of skin issues, but this morning woke up with a rash on her cheeks - it wasn't so much over the nose bridge, but definitely on each cheek.

Are there other reasons for her c3 and c4 to move around like that? Do "normal, healthy" people's levels go up and down so dramatically when sick/not sick? A doc thinks she is on the verge of flipping into a systemic immune disease, and we are waiting to see a rheumy.

Given the last two years (and what I read on here too), we will most likely hear her antibody tests are all normal, there is more in medicine that we don't know than we do speech. Everyone agrees that when she gets sick with anything, her kidneys and liver start to struggle, and we know now during those times that her c3 and c4 are low, with esr and crp in varying levels of high. Her c3 & 4 returned to normal after the flare was over.

Do rheumy's need a positive antibody test of some kind? I know it us only one criteria, but it seems to be the one the other docs have said "it can't be systemic as it's negative".

Any thoughts so appreciated! We are walking on eggshells - her getting a simple cold means so much more here! Thanks in advance....