I have small fiber neuropathy with possible ischemic neuropathy. they believe its an autoimmune response. detected by skin bx. is this fatal . ? ivig

Not usually: Neuropathy can be painful but usually isn't fatal. It can cause many other issues like wounds that don't heal. These issues can be fatal if not given proper attention. Discuss your fears with your doctor so they can guide you better.

Neuropathy: If your doctors suspect autoimmune disease then they should test you for that. Autoimmune conditions are treatable and not very fatal. It is not always easy to diagnose autoimmune diseases. I may require help from a rheumatologist. Also, your neuropathy might improve once the underlying condition is treated.