Please post back if you learn anything. My neuro said we could do the punch biopsy to confirm the SFN, but said it wouldn't tell us anything beyond that. And since he was confident in his diagnosis, he didn't feel it was necessary.

If the neurologist already confirmed that you have SFN, the punch test will not improve the diagnosi, since he has already Dx you with SFN. Now if for instance, you were to get the DNA test that showed CMT then he would be able to give you a more definitive answer. But even then, there wouldn't be a cure... The only time a Dx is real important is if it can be reversed in time, or if it proves to be suggestive of having more serious life threatening results. Right now Neurologists and Rheumitologists are just poking a stick in a dark room, they have no clue how to treat or cure PN.

one reason that you might want to insist on a skin punch biopsy is so that you can measure your progress over time. It would give you a current baseline. You can do additional skin punch biopsies in the future to see if you are improving or getting worse.

My neuro & GP said they won't do another one. I don't know why but I asked both and they said no. Said it wasn't needed.

That is sad to hear this. Repeat biopsies (especially after a course of treatment) to gauge improvement or disease progression is one of the best features of the biopsy.

How else can they tell if the fiber density has increased or gotten worse? You could consider printing some of the documentation that supports repeat biopsies...if you think they would even read it or be open to the idea. New medical technology does no good when doctors stop being teachable.

Thanks for all the additional information on the punch test.

This in the category of "for what it's worth," as I still don't quite know what to make of it, and I won't be discussing it in depth with my doctor for a couple of weeks.

After reading that 50% of all SFN cases are attributed to diabetes or pre-diabetes, and knowing that I have neither, but I do have issues with hypoglycemia, I requested an Oral Glucose Tolerance Test. In this test, they make you fast, drink this really sweet drink, and then test your glucose a 1/2 hour, an hour and two hours later. Oh, and they take a baseline fasting glucose level before you drink the stuff too.

As always, my fasting glucose was well below even pre-diabetic levels, but at the 1/2 mark, I was out of range too high, and then I came back in range at some point afterwards. (I'm still waiting for LabCorp to get their crap together two-weeks post-test and post my full results to my account so I can see them, but that's what the doc told me over the phone.) What the test didn't catch was that I became hypoglycemic at the 3 hour mark, but I expected that.

Anyways, what this test confirmed is that I do have a glucose metabolism issue with high spikes. Whether or not these issues could be responsible for the SFN, I don't know, but I'll be pursuing that. I have a glucose meter and will be experimenting and logging results just to see how prevalent these spikes are. I've not seen an endocrinologist yet, but that may be the next step. And for now, I'm treating myself as if I am diabetic and and am eating accordingly.

There are certainly reports--
 

--of people who have evidence of neuropathy, particularly painful small-fiber types, from glucose "spiking" that would not meet the criteria for frank diabetes to most doctors, just as there are reports of similar neuropathies in those whose fasting blood sugar levels are not in the "diabetes" range, but in the "impaired glucose tolerance" range.

Interesting that you note the "reactive" hypoglycemia at 3 hours, after the glucose tolerance test was ostensibly over. I have written here in the past that when I get a glucose tolerance test, I insist on an extended one with more frequent draws--baseline, every half-hour through three hours, then at four and five hours---along with analysis of insulin as well as glucose levels. The pattern of glucose rise and fall along with lagging insulin rise and fall--in particular, an overproduction of insulin to the moderate amount of glucose one drinks in these tests causing a driving down of glucose to hypoglycemic levels in the latter part of the test--is often an indication of insulin resistance in the tissues, which is a precursor to impaired glucose metabolism. (I have experienced this for many years; it seems to run in my family, and it is one reason I am very careful with dietary composition and timing.)

Thanks, Glenn. I'm doing a lot more reading on this.

For what it's worth, my fasting glucose is always in the low 80s and my A1c in the low 5% area. Neither fall in the range of even pre-diabetic.

Earlier, I found this seemingly good article by docs at the Cleveland Clinic.

http://www.ccjm.org/content/76/5/297.full

"Research findings strongly suggest that even prediabetes is a risk factor for small fiber neuropathy, and that so-called “impaired glucose tolerance neuropathy” may represent the earliest stage of diabetic neuropathy."

I've already set about changing my diet to a "diabetic diet." While I'm only slightly overweight and generally quite active, I have had a tendency to have a high carb diet that, while low in sugar consumption, is high in whole grains. I'd go days without eating meat and be perfectly content.

I'm working closely with a good friend now who is a severe diabetic after having had most of her pancreas removed. She has done a ton of research, and has been helping tremendously with supplement information as well as diet recommendations. She has also recommended "Dr. Bernstein's Diabetes Solution" book.

Searching my name and lists of posts--
 

--on this forum will bring up a number of links I have to lists of similar articles on neuropathy afflicting those with "merely" impaired glucose tolerance before frank diabetes.

Reactive hypoglycemia is quite frequently a precursor to impaired glucose tolerance. It's good to hear that at least your fasting glucose in quite good--but the logical question is what fasting insulin levels is it taking to keep it there. Quite frequently an insulin resistant person needs to produce a good deal of insulin to hold blood glucose levels in a "normal" range; as the beta cells of the pancreas tire and wear out over years from this activity suddenly one can get big glucose spikes, and impaired levels can happen seemingly overnight.

I finally got my hands on my oral glucose tolerance test results. Based on what I've read, they are not indicative of IGT, but I'm not sure about that because my doctor (not a PCT or diabetes expert) said something was out of range.

I became hypoglycemic at about the 2 1/2 hour mark, so my glucose was crashing, but any input on these numbers would be appreciated.

Fasting 80
1/2 hour 144
1 hour 181
2 hours 71

Thanks.
Janie