Hi, I have CVID. It is diagnosed through evaluation of four factors:
1. Levels of your (auto=this is wrong, sorry) antibodies (IgA, IgE, IgM and IgG). At least two have to be significantly deficient (well below the normal range).
2. Failure to achieve immunity protection from a high number of type of pneumonia from the Pneumovax vaccine. I had 6 protections out of 23.
3. A history of many and varied illness/very serious illnesses.
and sometimes;
4. A history of other Immune related conditions (eczema, asthma,Sjogren's,
Interstitial Cystitis, etc).
IVIG is a very very costly treatment, and only addresses a deficiency in IgG. It takes between 1000 and 10000 donors to produce enough IgG for ONE treatment. With a treatment every 4 weeks (for the rest of my life) that is 13 treatments a year. The cost of EACH treatment is upwards of $20,000.
Since I began my treatment in 2013, I no longer have illnesses, which is wonderful. But I continue to have progression of my small fiber neuropathy.
Neuropathy has many causes but often for those of us with Immune Disorder it is the result of our Immune System attacking our own organs/systems. Usually with autoantibodies. About 20% of those with CVID ( a form of Primary Immune Deficiency Disorder) have Autoimmune Conditions.
The Immune Deficiency Foundation
http://primaryimmune.org is a good source of more information and there is a patient forum:
IDF Friends › Log In
There are many causes of neuropathy, genetic, drugs, toxic chemicals, alcohol, nerve damage, diabetes, chemotherapy, and so on. Be sure your medical team is aware of the complexity of your situation.
And I always advise keeping a daily log of your health, moods, things of note. It is surprising how much we can learn from ourselves when we keep track regularly.
Hugs, Elaine D