Immuno deficiency with C3G

[KatrineM]

Hi HealthUnlocked,

I have a question regarding C3G and immune system function.

My son has C3Nef auto-antibodies. When they have measured his C3 levels they have been very low, first time round unmeasurably low. His SMac was very high.

He initially had a lot of infections, but they were not serious and treated by broad spectrum antibiotics.

Now his condition is more stable - he is in partial remission. How much would his immune system be effected by his disease, and should be take any precautions? His nephrologist has never recommended any.

best Katrine

[MPGN-C3G]

Dear KatrineM, your story sounds very similar like my son's one (He was 6 at the time of diagnosis). He had a number of infections and took antibiotics, however, one day his urine was brown and foamy like coca cola. Doctors at Charité in Berlin found out that his C3 is very low (almost unmeasurable), he has C3Nef and extremely high SMac (sC5b-9 was about 1000). They thought it is a result of the previous infections and waited for some weeks, but it got worse. Then, they started with cortisone, high immune suppression (mycophenolat mofetil or MMF, also known as CellCept) and ramipril. He went into remission for some weeks, but his C3 stayed at 18 (instead of 90) and after 4 or 5 months he leaked more and more proteins in urine. They said, this disease leads in 50% of cases to dialysis after 5-10 years. Since his SMac was still very high (600 instead of 200 normal), they started with Eculizumab (of course we had to fight for it with the health insurance because it is extremely expensive, approx. 11,000€ for a child's dosis every 3 weeks).

Just some days after we started, my son had no blood in the urine anymore. Proteins in urine went down. After 3 months, his SMac dropped to a normal level. Now, more than a year later, he is gaining weight and can do sports like a normal child. However, his C3 is still too low (24) and C3Nef is still positive.

But as far as I understand this disease, it is very important to keep SMac low and Soliris is obviously the right medicine to do this. These SMac complexes destroy the kidneys very quickly. The other process that is going on is the deposition of C3. Soliris cannot stop it, so, the disease is progressing. But I hope, there will be a new medicine one day to solve this problem, too. Until then we will try to prolong the kidneys' life with Soliris as far as our insurance agrees to pay.

By the way, he still takes MMF and Ramipril. Additionally, he takes Penicilline as meningitis prophylaxis (Soliris patients have a high risk to get meningitis, so, antibiotics are recommented as protection).

I hope this answer helps you somhow. By the way, you can ask experts for their opinion on this website. I have done this once, I had a question about a genetic investigation that showed that my son has a predisposition to aHUS - a disease related to C3G. The answer was very helpful.

And you can join our facebook group with more than 200 C3G patients and caregivers world wide: facebook.com/groups/1596621...

[DavidF_NKF Partner in reply to MPGN-C3G]

Hi Katrine,

Thank you very much for your question, It is being sent to our expert panel and a response will be posted as soon as they develop their reply. And MPGN-C3G, thank you for your kind reply.

[KatrineM Ambassador in reply to DavidF_NKF]

Thank you very much David and MPGN-C3G, it was very kind.

I think we may know each other from the patient group, MPGN-C3G We are in Copenhagen!

[DavidF_NKF Partner in reply to KatrineM]

Hi Katrine,

Here is the response from our Expert Panel to your question. And yes, we know each other (by email). I hope you and your family are staying healthy during this difficult time.

Thank you for this question. You are correct to think that a low C3 level may predispose to infection. However, a person’s immune defense is very complex and with age becomes better developed. Complexity offers redundancy, which means that even with a low C3 level, other aspects of immune defense compensate. Perhaps the best example is when a person is born with an inherited deficiency of C3 and therefore has no C3 at all. There are only a few examples of such children and most, but not all of these children, did have repeated infections. The infections, in those persons who got them, were caused by encapsulated bacteria like as Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis, but again, not all children had repeated infections.

In your son’s case, treating bacterial infections with antibiotics is wise. You also mention that your son is now in remission. If his C3 levels have come up, even a little, they will help in fighting infections. In addition, he should receive his regular childhood vaccinations, and as he gets older, other aspects of the immune system will offer additional protection against infection.

As with anyone who is potentially immune suppressed, it would be best to follow general practice recommendations to limit risk for contracting an infection: lots of good hand washing, avoiding obviously sick people, and consider avoiding large gatherings of people when a particular infection seems to be circulating in a given community (i.e. the flu).

[KatrineM Ambassador in reply to DavidF_NKF]

Thank very much for the great answer!