Small-fiber neuropathy is a common disorder. It is often idiopathic in nature (meaning the cause cannot be found out). Autoimmune mechanisms are often suspected, but rarely identified.
Toxins can lead to this condition. Several toxins, including alcohol, arsenic and metronidazole (an antibiotic) preferentially affect small fibers.
The other known causes of small-fiber neuropathy include diabetes mellitus or glucose intolerance, amyloidosis, toxins, inherited sensory and autonomic neuropathies, Sjogren’s syndrome, lupus, sarcoid, nutritional deficiencies, celiac disease, hereditary conditions including Fabry disease and Guillain-Barre syndrome. In cases where no cause can be found, the neuropathy is called idiopathic.
Diagnosis is made on the basis of the clinical features, normal nerve conduction studies, and abnormal specialized tests of small-fiber function.
Hope it helps.
When a dr does think a patient has small fiber neuropathy and performs a blood test is it the "norm" to only do 2 sites(top of foot and ankle) or 3? I have heard that the way to know if a patient has non-dependant small fiber neuropathy is to do a thrid site- either thigh or arm. My skin started burning in my arm the first time, and when blood flowed back in caused emmense pain and then in my upper back. Over the months it now covers stomach arms thighs and even buttoks. The last place to burn was my feet. When I returned for the results of my test he told me I only hve sfn in my feet as the biopsy of the ankle was negative. He also said no where in the world would a dr link my burnring back and arms to sfn. But then I read about the third site. How do I address this with the doctor? He is supposedly the best in our province and I do not want to come across arrogant or rude. He is the last doctor that may be abe to find out answers I've been waiting for for 15 years. It is a complex case -starting with only weakness balance and sight problems, moving into muscle and joint pain and now this. I am sure in my file hhe has seen comments from other drs thaat are not kind to my state of mental health. It appears wanting anawers make you crazy in their eyes. Could you please advise me how to deal with this?
I made a mistake in my post!!" When a dr does think a patient has small fiber neuropathy and performs a blood test.." SHOULD read ...and performs a skin punch biopsy, is it the "norm" to only do 2 sites...
Sorry, I hope this makes more sense and someone could please reply.