New here--Large Fiber PN
 

Hello everyone
I'm new here. My name is Sarah Mae. I'm 24 years old and from South Dakota. I recently (in May) graduated from college with a degree in Elementary Education. However, last August I had gastric bypass surgery. In December, I started to have some pain in my feet. I didn't think anything of it, and started my student teaching semester in January. The pain started to get worse and worse--to the point where I would stand up and teach for 8 hours and then come home and cry for 8 hours. I couldn't stand the pain, but my doctor couldn't figure out what was wrong.
I went to doctor after doctor, and nobody knew what was going on. Finally my mom took me to Mayo Clinic in Rochester, MN. Four days of painful tests later, they told me that I had large fiber peripheral neuropathy. I was on gabapentin at that time, so the doctor had me increase my dose to 2700 mg (slowly, of course). I did, but it didn't help.
I have been working with my neurologist back home here (an hour away from my home), and he has switched my medicines a few times. The gabapentin didn't work. We tried topamax and amitriptilyne (sorry if I'm spelling these wrong) and now I'm on Lyrica... but that isn't working yet either. I'm so frustrated, because I am in incredible pain.
I have been reading posts from people, and it seems like the majority of you have small fiber PN. I can't seem to find any good information on large fiber PN on the internet--can anybody help me? I have all the symptoms of small fiber PN--I have the burning, the electrical shocks in my feet... but the tests show I have large fiber PN.
I am bedridden at this point because the minute I swing my legs over the side of my bed, my legs turn purple because the blood rushes down to my legs and feet... and doesn't pump back up.
My neurologist said that my neuropathy is a result of the gastric bypass surgery. It's because my body stopped absorbing vitamins. It's not that I wasn't eating well enough... it wasn't my fault at all, but it was just my body. He said that this is one of the most severe cases of neuropathy--and the worst that he has ever seen. I am in bed 24/7 except when I walk less then 10 feet to the bathroom.
Nobody around here understands this. I don't know anyone with neuropathy or anyone who even knows what it is. So I'm hoping to meet some people and really... to make some friends here that I can relate to.
Depression goes hand in hand with chronic pain. I have had chronic pain since I was a child, because I have degenerative disc disease and other things (arthritis and things) in my back... and I am very thankful that I do not deal with depression. I have bad days, but I am generally in high spirits. But I would just really like to find some people that can relate to my situation.
Now that I've written a book... I'm not sure anyone will read and respond... haha... but I really would like to know if anyone has any websites that explain the difference between small and large fiber neuropathy... because I don't know what the difference is... thanks for reading!

Oh, that is terrible. I thought the bariatric surgery directions made sure that you get the proper vitamins! Most bariatric patients I've seen have to use liquid ones.

Also affected is fatty acid metabolism. This condition occurs in other people who lose alot of weight suddenly..and appears in the literature sometimes as "slimmer's paralysis".
The insulation of the nerves is composed of fatty acids, and when these are no longer eaten from food, the nerves cannot maintain themselves. B12, folate, and B6 + omega-3s are crucial to the nerve sheaths.

One bariatric patient I used to see, developed chronic low blood pressure from nerve damage. She was always fainting. I always wondered what happened to her, when I moved on to another location.

I think you will need intensive nutritional support, and maybe IV vitamins to help you get over this serious side effect.

Thanks for your reply. I took a long list of vitamins before surgery as well as after surgery. I am taking even more vitamins now. It's not that I am not taking them--it's that my body wasn't absorbing them correctly. I took large amounts of vitamin D for several months--50,000 IUs... and stayed at less than 4 IUs (when you should be between 30 and 100 IUs). My body just wasn't absorbing it for some reason, even though I was on the high dose for several (7 or so) months.
I just can't seem to find any information about large fiber neuropathy. I don't know what the difference is between small and large fiber PN is.
I have been told that neuropathy after GBS has a good chance of going away... though with this being such a severe case, it may be like this for life. Who knows...

If you are taking the D2 RX 50,000 IU's ...this form generally is far inferior to D3.

You can get your D from the sun too.

You may have to get some IV support for your vitamins soon.

Long fiber damage is to nerve axons that have a myelin sheath.
This is going to affect motor functions as well. Unmyelinated fibers are basically sensory in type.

This article explains the different types.
http://www.ninds.nih.gov/disorders/p...neuropathy.htm

Sorry, I should have been more clear in my last message. I am not sure what the 50,000 was... but I was also taking 5,000 IUs of D3 a day. FINALLY, I had blood work done in late June and my Vitamin D level was at 66. So my level finally straightened out. In fact, my B12, D, and all my other levels are all back to normal as of my June blood work. I'm still taking my vitamins and getting my monthly B12 shot. So I think I'm in the clear as far as the vitamins go.

But, of course, the neuropathy is still here. The damage is already done.

Thanks for the link. I am going to go look at it right now. :)

normal levels of b12 may be based on out of date numbers. as far as b12 goes you should be taking it everyday and not depend on a once a month shot to provide you what you need. you are going to have to do some research here on some of these topics to understand all that is being discussed. as im sure you have deduced, since your pn resulted from vitamin deficiencies due to your bariatric surgery and even with treatment with vitamins since then your symptoms continue you need more than what you are getting now or vitamins that are not being supplied to you.

actually most people have large fiber neuropathy who have PN. It is what shows up on an emg though it may not show up until enough damage has been done. i have large fiber pn with axonal involvement affecting the sensory nerves and to a lesser extent the motor nerves. The myelin sheath around the large fiber nerves are also being affected because of the degeneration of the axon. some people with large fiber only have axonal involvement or demyelination of the myelin sheath. there are also people with mixed large and small fiber neuropathy.

I definitely do. I take a multivitamin that has 200% the daily recommended value of B12 and also take an additional B12 supplement. I don't just rely on the B12 shot.

Everyone that I've seen on here has said they have small fiber PN.. you're the first to say they have large fiber PN. As I said in my original post, I also am having a hard time finding any good websites about large fiber PN. I have all the symptoms of small fiber PN, so I'm not sure why my doctor says I have large fiber PN... but then again, since I can't find out in simple terms what it is and what the differences are, who knows. I just want to find out in simple terms what the differences are in terms of symptoms and such.

I did read that whole site... and I found a lot of very good information, but not about large fiber PN. Maybe I am just stupid. I don't know. I am new to all of this and I am not medical minded. I don't understand medical terms and that's why I am asking for a website that explains it in simple, everyday terms. I just want to know in everyday language what the differences are in the symptoms between the two (large and small fiber). If I have all the symptoms of small fiber, why does my neurologist tell me I have large fiber PN? I can't find any websites that explain large fiber PN and what symptoms come with it (that I can understand). I did order a book off of Amazon, but it hasn't arrived yet.

this is a simplified explanation

SMALL FIBER NEUROPATHY

Small fibers (C-fibers) provide mostly sensory and autonomic innervations. The sensory fibers (unmyelinated and thinly myelinated) perceive pain and temperature changes. The autonomic fibers controls for heart rate, blood pressure, sudomotor function and gut function. Small fiber neuropathy mostly involves thermal perception, which means that pain is in the form of cold, warm and hot. Clinical presentations of small fiber neuropathy include hyperesthesias ( increase in sensitivity to stimuli, such as pain out of all proportion to injury or even contact with an object), hyperalgesia (increased sensitivity to pain), excess sweating and impaired microcirculation.

LARGE FIBER NEUROPATHY

The large fibers are myelinated motor fibers. These fibers are responsible for motion control, touch (such as numbness), proprioception (knowing where your body is, such as if your feet are numb you will not know where they are on the floor or even their position) and vibration. The myelinated sensory fibers also perceive for touch, proprioception and vibration. The clinical presentation in patients with large fibers neuropathy are impaired vibration, gait instability, weakness, numbness, small muscle wasting and commonly radiating or cramping pain at night.

I would suspect--
 

--that you probably have both large and small-fiber disruption, given your poor nutritional status. But the testing you may have received may have only revealed the grosser large-fiber disruption; small-fiber is harder to definitively diagnose (the current gold standard is skin biopsy to measure intrepidermal nerve fiber density and condition).

Large fiber neuropathy can be found using more standard nerve conduction/EMG tests, and since abnormal readings on these usually mean fairly extensive and unequivocal damage, I'd say you're pretty compromised.

AND--what doses of supplements are you taking? It's pretty standard post-bariatiric surgery that there be massive supplementation, as most of the area from which you could absorb nutrients is gone. I would think, for example, you should be on at least 5000mcg/day of B12, to allow passive absorption of 1-2% of that amount. I'd also think you should be supplementing calcium, magnesium, the other B-vitamins, D (probably at least 5000IU/day if you don't get out in the sun much) and definitely essential fatty acids . . .

Thanks, echoes long ago, for that information. That makes some sense to me, and that's what I've been looking for. It does sound like I have both large and small fiber, as glenntaj has suggested. I didn't know that was possible, but I have symptoms of both. I had a lot of tests, but never a skin biopsy. I appreciate you giving me that information!

I don't have my medicines with me right now, and can't get to them... but I know I'm taking 5,000 IU/day of D3 a day (and it is in my multivitamin as well). I am taking B12 every day and it is in my multivitamin and I also get a monthly B12 shot--my B12 levels are where they need to be, so I am getting enough of that. I take a calcium supplement (which also has Vitamin D in it) every day. I take a B complex as well and my doctor said that those levels are all where they need to be. I am not taking any magnesium--I had asked my doctor if I should take some because a friend suggested it, but he said not to take it because my magnesium level was high enough and he said that I was fine without it--I take about 30 pills a day and he said that if I didn't need it, that I didn't need one more pill. I don't know what you mean by "essential fatty acids"... so I suppose I'm not taking those....

I don't know about the rest of you, but my my toes are very very sensitive. The front half of my feet are numb, and that is where the nerve damage is. It feels like all 10 of my toes are broken, and even a slight touch, a sheet covering at night, or a slight breeze from a window or fan can send me over the edge and make me scream or cry out in pain. I walk on my heels and the side of my feet because I can't put any pressure on the front of my feet.

I am pretty much bedridden, only getting up when I need to go to the bathroom (which is less than 10 feet away). Today I was walking to the bathroom and somehow managed to fall. I ended up twisting not only one, but both of my ankles. I hurt both of my ankles and hurt both of my feet.

I was already having a very bad pain day to start off with, and now I am having these incredible burning shooting pains into my ankles. I am not sure if I twisted or sprained my ankles, but wow... what a day.

Did you have a test for small fiber PN?
 

There are only 2 tests that I've heard of for small fiber PN and not all Drs. are real aware of the one test, the skin-punch biopsy. You have the burning and as you say, symptoms of sfpn. I don't remember the other test, I think it's a sweat test or something like that, maybe someone else will post. Small fiber PN is when the tiny nerves in our skin are damaged.

I had the skin-punch and it's very easy on you to have done and Johns Hopkins will do the checking on your skin samples and results by mail. I can give you the details if you want. Just post me a private message here and I'll look for it. You would have your Dr. get the skin samples, I had 3 and you mail them to Johns Hopkins in Baltimore, MD. Or you may be close to one of the few places that does this test in the US. There may be around 10-12 now.

There are a few other tests--
 

--that can imply small-fiber disruption: there is quantitative sensory testing, in which an electrode that can assume various temperatures is used to determine one's sensitivity to hot and cold (those this relies on self-reporting), and there are also autonomic tests such as the sudomotor axon reflex (sweat) test. But skin biopsy is currently the most definitive.

Essential fatty acids are the type found in fish oil, flax, etc.--Omega 3's primarily (we tend to get not enough omega 3 and too much omega 6 in standard diets), and these are necessary for proper maintenance of the myelin sheathing of large nerve fibers.