Hi Rachel @rwinney, That's really a good question but I'm not sure of the answer. I think it's possible to have both small and large fiber neuropathy together but the only reference I could find was related to diabetic neuropathy.

Small- and Large-Fiber Neuropathy After 40 Years of Type 1 Diabetes
-- https://care.diabetesjournals.org/content/36/11/3712

The Neuropathy Commons website has one of the better overviews of neuropathy that may be helpful.
-- https://neuropathycommons.org/neuropathy/neuropathy-overview

John