Hi Lindyloo

From reading your previous thread I understand you're still searching for the cause of your husband's PN, (which was originally labeled idiopathic), after a long period since the original diagnosis.

You mention above that he is already being treated for Hypothyroidism - Peripheral Neuropathy can be secondary to Hypothyroidism. It is not uncommon that even though a primary condition may be being well managed the secondary PN may not resolve. Is your husband's hypothyroidism the autoimmune type? (ie: Hashimoto's Thyroiditis)

Trying to find an alternative possible cause in the presence of an already existing disease becomes very difficult, as it might be impossible to eliminate it as the cause.

Here's a link to a report on several case studies: (it's an old report but it has some specific details on neuropathy with hypothyroidism)

http://jnnp.bmj.com/content/50/11/1454.full.pdf

Regarding the tests you are considering requesting; I know that testing in the US is expensive so maybe try to narrow the list down to those most likely first. Also you might want to discuss it with your PCP who could guide you knowing your husband's history.

This link might help you to sort out which tests may be relevant.

Laboratory Diagnosis of Peripheral Neuropathy

All the best for finding answers. Let us know how you get on.