I'm 77 and 1 1/2 yrs into a biopsy/immunofluorescence confirmed diagnosis of C3G (my kidneys were spilling small but increasing amounts of protein for several years before diagnosis). I've had a work-up by the Renal lab at the Univ. Iowa, USA and they found none of the predisposing factors for C3G. My nephrologist has repeatedly looked for auto-antibodies (AKA "para-proteins) that might be affecting my Complment Alternative Pathway and can find none, so I am considered idiopathic with respect to cause.
I am 7 mo in on a Prednisone/Mycophenolate (MMF) regimen that started at 40 mg/d Pred and 2000 mg/d MMF and now at 5mg/1000 mg/d for past 6 weeks. My eGFR fluctuates around mid 40s to high 50s, my serum creatinine around 1.2-1.3 mg/dL and my urine protein from 300-500 mg/d (using urine protein/creatine ratio). My C3 level has improved during treatment to just at the lower end of normal.
I have new labs and see my nephrologist in 2 weeks and hope to get off both drugs but especially Prednisone. I completd the Moderna COVID-19 vaccine 6 weeks ago and today went to a lab in Portland, OR to get a test to see if I actually made any antibodies. I'll know results in "2-3 working days".
I haven't met anyone else as old as me with C3G (I belong to Nephcure and We C3G-both helpful). I realize I'm lucky to have lived a full life without this disease and I so respect and feel for all you mothers out there who are trying to understand this and get help for your young son or daughter. I hope treatments will improve and be affordable
I'm a retired college microbiology/immunology teacher (32 yrs) so I am fortunate to understand a good bit of this, but it was hard to get undergraduates in my Immunology course (nearly all of whom became health professionals) to understand the complement system-especially the Alternative Pathway@#$!