Small or large fiber neuropathy - What percentage is idiopathic?

@nukhan, I have idiopathic small fiber PN and have asked that question before and received slightly different answers. The best answer was from an 80 year old neurologist at the support group meeting for the Minnesota Neuropathy Association. His answer on why it's idiopathic was because the idiot neurologist was not able to provide a diagnosis. Then he said the number is probably around 20+ percent of those diagnosed with neuropathy.

From Lab Tests Online - "Causes -
According to the National Institute of Neurological Disorders and Stroke (NINDS), more than 100 types of peripheral neuropathy have been identified. When the cause is unknown, it is referred to as idiopathic neuropathy; about 23% of cases are classified as such."
-- https://labtestsonline.org/conditions/neuropathy

From Healthline.com - Idiopathic Neuropathy
"How common is idiopathic neuropathy?
Approximately 30 percent of neuropathy cases are due to diabetes, according to the Cleveland Clinic. Between 30 and 40 percent of the remaining cases are idiopathic.
-- https://www.healthline.com/health/idiopathic-neuropathy

Hello @johnbishop. I agree with you that "idiopathic" is a cop out. Once the "standard" testing rules out the "usual suspects", many neurologists will punt. An excellent nurse once told me she wouldn't just accept such a "suspicious" "cause". It seems to me that in too many cases the doctor just doesn't want to go through the myriad of tests it would take to get the actual cause. There is, of course, the matter of paying for all those additional tests and whether or not the generous insurance companies will cover the costs.

@lagrange5 - I think you have a point about many neurologists just doing the punt because they can't determine a cause. But, it also has to do with the neuro doc. I've been to my fair share in past 8 years and with my PN, I have symptoms that even Mayo in MN could not explain. Not all neuro docs specialize in PN and I found that out! By the way, Mayo did the most comprehensive tests of anyone. So, many of us remain idiopathic. Could it be because symptoms vary to such a high degree? Or, is it because of the huge number of causes? Or, as you suggest, tests are costly and no matter what, insurance companies with little knowledge about PN determine the ability to get tests. Probably a combination of them all. I've been told my cause could be my back, oh no, it could be toxic exposure, oh no it could be genetic. Oh no, it's idiopathic! Or, the best one....even if we find out the cause, there is no cure. That'll stick with me for a while! Let's face it, there is always a cause for everything, Finding the causes are not the top of the list in our medical community.

@njed, I read an excellent medical article written by PN specialists for internists and other professionals. It might be helpful to you too. It was linked in the discussion group, "SN in feet" on February 19th by @larry4343. One takeaway for me is that alpha lipoic acid has been prescribed. It's a long read, but I think it's worthwhile.

@lagrange5 - I had missed this back on 2/19 - found it and printed it. Thanks to @larry4343 as well for the link!! This is what this connect is all about...helping out others. Ed

For anyone who missed the article shared by @larry4343, here it is again...

--- Peripheral Neuropathy: A Practical Approach to Diagnosis and Symptom Management:
https://www.mayoclinicproceedings.org/article/S0025-6196(15)00378-X/pdf
Along the same line there are some really helpful videos - This short video by Matthew B Jensen Assistant Professor of Neurology, University of Wisconsin that gives a good explanation of how the different neuropathies are diagnosed. He also has a YouTube channel with a lot of different neuropathy explanations.

Glad to help, Ed. Just pay it forward.

@lagrange5 - I always have and always will. Thanks again.