Getting scared again
 

I was diagnosed with full body SFSN 2 years ago, I have been noticing in the last couple of days that I'm feeling weaker in my legs , I know Small Fiber can turn into Large Fiber and I'm worried this might be happening to me, my last EMG was done in June of last year "2012", it was my 3rd EMG and it was Normal. So my question is, Can Small Fiber Sensory Neuropathy cause weakness?:confused: thanks for your help. Jan

Luke 1:37, Nothing is impossible with God.

Hi Lift,

I guess you should try to differentiate between actual weakness and a "feeling of weakness". With feet flat on floor lift up on both the balls of your feet. Any weakness? Again with feet flat on floor lift feet off ground keeping heel on floor. Any weakness there? Can you balance on one leg? Is it relatively the same on both sides? How do you feel going up and down steps? Small fibre can cause many funny feelings and I have had a feeling of running water down my legs which made me feel wobbly and weak but no true actual weakness. Same with numbness. I have migrating numb spots all over but no true numbness. Only a feeling of numbness.

Liftyourhands7--
 

--sent you a PM--and I agree with Aussie you do have to distinguish between feelings of weakness and actual weakness, such as her quick testing may help you determine.

Small fiber neuropathy by definition will not cause weakness as it involves only sensory nerves that subsume pain and temperature sensations and some autonomic systems. But the feelings one can get can be so varied it may feel like weakness, so actual muscle testing may be called for. And, as you mention, sometimes syndromes that start out as small fiber will spread to larger fibers, including those that control motor functions; the process (whatever one) that affects the axons (nerve fibers) of the smaller nerves may also affect the larger ones.

I started out many years ago with just numbness in my toes, I was in my early 30's, and pain, not weakness, in my legs. I ascribed the pain to varicose veins and ignored the numbness. I was 47 by the time I got to a neurologist and by that time the numbness had extended to mid-calf and I was having pain, weakness, and balance problems. Skin biopsy showed SFN, EMG showed LFN, both advanced. I now have pins and needles up to my hips and upper arms.

But I have a hereditary neuropathy, primarily axonal, and they do progress this way. Has your doctor ruled that out? I was always very strong until the past few years ( I'm 51), but was clumsy and uncoordinated since childhood.

I started the same way first in my toes tickling then numbness and pain very slowly moving up to mid calves burning pins needles , mild loss of sensation in thighs. Neurologist doesn't know what my cause is , so I quit drinking because I was a heavy drinker just to see if it would get better, I am slowly getting better I think. He never mentioned a skin biopsy what will that tell me ? My was in my early 40's when it started and now am 47 it has diminished my quality of life to the point sometimes just walking to the bathroom is a struggle. I wish I could find out if I had hereditary neuropathy my dad died when I was young and my mother died 6 years ago , but I do have a brother. Sorry I am new here and to all this, hang in there, Peace !

You can have DNA blood testing but it is very expensive. Also, look at family history other than your parents. With CMT you can be young, old or in-between before you have any evident symptoms. Or you may not have evident symptoms at all. There are many many types of CMT and also many types of PN. Hope you find an answer.

I am in the same boat without much info about my bio dad, but he had a daughter who wore leg braces from early childhood, so the link is there. If you are improving then it isn't a hereditary neuropathy, they always progress, although at different rates.
A skin biopsy will just tell you for certain that you have small fiber neuropathy, and may give you some idea of how advanced it is, but it will not tell you the cause. Have you had an EMG? That will tell you if there are large fiber or muscle involvements.
There is a lot of information on here about healing with supplements, diet, etc. if you are improving than you will benefit from reading as much as you can about that. Good luck!

Thanks everyone, I have an appointment with my neurologist the end of March, I will let you all know what he says, I'm thinking he may do another EMG to see if I have any Large Fiber involvement. I wish they could tell me what's causing this so I could have a chance at trying to correct it. I do suffer from hypoglycemia due to a stomach surgery I had 9 years ago, I'm also seeing that some people who have had gastric surgery suffer from neuropathy, it's pretty hard to pinpoint the problem, maybe my neuro Doc will have more information for me when I see him at the end of the month. Thank you, Jan

Luke 1:37 For nothing is impossible with God.

sfn biopsy
 

Is this biopsy painful? What part of the body do they biopsy? Is it a nerve or muscle biopsy? Thank you for the feedback.

The biopsy for small-fiber neuropathy determination--
 

--is much less invasive than nearly any other kind of biopsy--it is a skin punch biopsy.

Usually, 3mm wide, 1 mm deep circular skin samples are taken from the skin just above the ankle, at the thigh, and sometimes just above the elbow--these are the sites that the most work has been done it terms of standardization to "normals". Technically, though, this type of biopsy can be done anyplace there is hairy skin.

The samples are then stained and examined under an electron microscope to determine the intraepidermal nerve fiber density and the condition of the fibers themselves.

Many places can remove the samples--it's very simple and something almost any doctor can do--a small shot of lydocaine or other local pain killer, a quick sampling and collection, and you walk out in ten minutes with some band-aids. The analysis, though, tends only to be done at very specialized centers (Jack Miller, Columbia Presbyterian, Massachusetts General, etc.), so often the samples are sent there.

The procedure has the advantage of being repeatable at the same sites over time for comparison purposes--I've had it done three times, and it has documented slow but definite re-enervation.

See:

http://www.medscape.org/viewarticle/563262

This is an excellent overview, and the reference list has about as many other papers on the procedure as you'll likely ever need.