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    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of and finding treatments for complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia (FM), long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

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xebex

Senior Member
Messages
840
I haven't been diagnoses with SFN, mainly because i haven't bothered to go to Doc as i have no pain which seems weird. What i do have is numb skin on my ankles so when i shower the sensation of the water on my skin is different to that of the rest of my legs, I also seems to be loosing hair on my legs (but i still have hair on my ankles), and if i stand or sit with my legs dangling down for too long (10mins or more) my feet start to sting/burn and go blue.

Does this sound like SFN? What are the treatments if i don't need pain killers?

Is it likely that this SFN is contributing to my non POTS orthostatic intolerance? Im assuming its blood pooling in my feet which causes hypoperfusion in my back muscles which seems to be what triggers my crashes.

Any other thoughts?
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
What i do have is numb skin on my ankles so when i shower the sensation of the water on my skin is different to that of the rest of my legs, I also seems to be loosing hair on my legs

That sounds very much like it could be small-fiber neuropathy.

Is it likely that this SFN is contributing to my non POTS orthostatic intolerance?

To me, it seems more likely that the orthostatic intolerance is contributing to the small fiber neuropathy. When orthostatic intolerance lets blood pool in the feet and ankles, it means that blood is not flowing properly throughout the feet and ankles, starving the small nerve fibers of oxygen. (i.e. the pooling blood is lacking oxygen)

EDIT:
Small fiber neuropathy (SFN) is well-documented to occur when there is an inconsistent supply of oxygen or nutrients to the small nerve fibers. This is notably demonstrated in the case of diabetes, where a lack of a consistent supply of glucose leads to SFN.

From a 2006 paper by Anne Oaklander:
https://doi.org/10.1126/sageke.2006.6.pe7
Any disruption of the [...] energy supply (oxygen, glucose, [...], or mitochondria) required to keep axonal transport functional can thus cause distal axonal damage.

("distal axonal damage" = SFN)
 
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bread.

Senior Member
Messages
499
That sounds very much like small-fiber neuropathy.



To me, it seems more likely that the orthostatic intolerance is contributing to the small fiber neuropathy. When orthostatic intolerance lets blood pool in the feet and ankles, it means that blood is not flowing properly throughout the feet and ankles, starving the small fiber nerves of oxygen. (i.e. the pooling blood is lacking oxygen)

There is no other way than the problem being bidrectional.
 

xebex

Senior Member
Messages
840
thanks @bread and @Pyrrhus, ok so I guess I need to be tested for SFN then. Is it a thing that doctors get or will I get more eyerolls?

I do believe then that the nervous system causes blood vessels to dilate causing the blood to pool which then damaged the nerves and causes SFN.
 

Mohawk1995

Senior Member
Messages
287
I do believe then that the nervous system causes blood vessels to dilate causing the blood to pool which then damaged the nerves and causes SFN.

xebex,

It is important to note that "neuropathy" does not necessarily mean damage. It can mean "unhealthy" or "dysfunctional". There are indeed neuropathies that result in damage, but most appear to be more unhealthy. Instead of thinking of the nerves as either damaged or not, I find it best to look at them in a spectrum of health from severe to very mild neuropathy. Small fibers are the most sensitive in general and also the most frail. Blood flow restriction, even very mild can create parasthesias (numbness, tingling, odd sensations) very easily. Also instead of thinking damage or no damage, it is best to think in terms of healthy or unhealthy. With the focus on improving the health of the nervous system including emphasizing: Restorative Sleep, Moderation of intake especially powerful substances like alcohol, nicotine and other stimulants, Movement, Blood Flow and addressing/working your way through stress.

It is also important to note that you want to enhance the health of the entire nervous system as "when you affect any part of it, you affect the whole".
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
There is no other way than the problem being bidrectional.

Yes... and no. (a bidirectional response!) The orthostatic intolerance is caused by dysautonomia, which can include autonomic neuropathy, where the autonomic nerves that control the veins in the legs fail to constrict properly upon standing, leading to blood pooling in the legs. So, in this sense, autonomic neuropathy contributes to orthostatic intolerance.

But, because of the orthostatic intolerance and the blood pooling, there is not enough oxygen to support the small-fiber nerves in the feet and ankles, leading to the death of the small-fiber nerves. So, in this sense, orthostatic intolerance contributes to small-fiber neuropathy.

It is important to note that "neuropathy" does not necessarily mean damage. It can mean "unhealthy" or "dysfunctional".

Good point. In this case, the "autonomic neuropathy" refers to a dysfunctional, but intact, nerve.
But the "small fiber neuropathy" refers to nerves that have died and are no longer there.

I do believe then that the nervous system causes blood vessels to dilate causing the blood to pool which then damaged the nerves and causes SFN.

Yes, that's it. Except it's not that the veins dilate upon standing, it's that the veins fail to constrict upon standing, allowing gravity to lead to blood pooling. If you simply elevate your legs, gravity will then stop the blood pooling.

EDIT: Discussed further here:
Orthostatic Intolerance Basics: Dysautonomia of Blood Vessels, Low Blood Volume, and Baroreflexes
https://forums.phoenixrising.me/thr...sels-low-blood-volume-and-baroreflexes.86445/

ok so I guess I need to be tested for SFN then. Is it a thing that doctors get or will I get more eyerolls?

Small-fiber neuropathy is a well-recognized condition, and neurologists have a simple test to diagnose it: a skin-punch biopsy. So, if you mention to your neurologist that you are experiencing numbness and hair loss in the feet and ankle area, they should order a skin-punch biopsy to check for small-fiber neuropathy.

However, if you then ask the neurologist to treat the small-fiber neuropathy, you may get some eye-rolls. Unfortunately, you can only treat small-fiber neuropathy if you know the cause, and it is a treatable cause.
 
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xebex

Senior Member
Messages
840
Thanks for that detailed response @Pyrrhus it all makes sense what you are saying. I Do believe I have autonomic neuropathy but this numb skin seems to suggest some kind of damage just in that small area. No idea what the cause could be, have gone through many avenues. I generally don’t bother going to docs as I’m aware there’s no “cure” for anything and when I’ve tried meds like Mestinon I’ve had awful side effects. As I said Ritalin is sometimes helpful and doc was helpful enough to prescribe that. Problem is I build tolerance fast and it causes rebound symptoms so I can only take it once or twice a week. And of course in the long run it’s probably not helpful at all sigh.
 

bread.

Senior Member
Messages
499
Yes... and no. (a bidirectional response!) The orthostatic intolerance is caused by dysautonomia, which can include autonomic neuropathy, where the autonomic nerves that control the veins in the legs fail to constrict properly upon standing, leading to blood pooling in the legs. So, in this sense, autonomic neuropathy contributes to orthostatic intolerance.

But, because of the orthostatic intolerance and the blood pooling, there is not enough oxygen to support the small-fiber nerves in the feet and ankles, leading to the death of the small-fiber nerves. So, in this sense, orthostatic intolerance contributes to small-fiber neuropathy.



Good point. In this case, the "autonomic neuropathy" refers to a dysfunctional, but intact, nerve.
But the "small fiber neuropathy" refers to nerves that have died and are no longer there.



Yes, that's it. Except it's not that the veins dilate upon standing, it's that the veins fail to constrict upon standing, allowing gravity to lead to blood pooling. If you simply elevate your legs, gravity will then stop the blood pooling.



Small-fiber neuropathy is a well-recognized condition, and neurologists have a simple test to diagnose it: a skin-punch biopsy. So, if you mention to your neurologist that you are experiencing numbness and hair loss in the feet and ankle area, they should order a skin-punch biopsy to check for small-fiber neuropathy.

However, if you then ask the neurologist to treat the small-fiber neuropathy, you may get some eye-rolls. Unfortunately, you can only treat small-fiber neuropathy if you know the cause, and it is a treatable cause.

Dysautonomia itself can be explained by SFNP.
 

Pyrrhus

Senior Member
Messages
4,172
Location
U.S., Earth
There are also many other interesting discussions about Small Fiber Neuropathy, and its possible relationship to dysautonomia:


Small Fiber Polyneuropathy (SFPN) Proposed as Cause of Exercise Intolerance In ME/CFS
https://forums.phoenixrising.me/thr...ause-of-exercise-intolerance-in-me-cfs.80617/


Small-Fiber Polyneuropathy May Underlie Dysautonomia in ME/CFS
https://forums.phoenixrising.me/thr...hy-may-underlie-dysautonomia-in-me-cfs.82250/


Leg hair loss (leg alopecia), a sign of neuropathy in Diabetes, 2019
https://forums.phoenixrising.me/thr...-a-sign-of-neuropathy-in-diabetes-2019.80273/


Length-dependent Small Fiber Polyneuropathy Caused by Coxsackie and Influenza Virus CoInfection
https://forums.phoenixrising.me/thr...sackie-and-influenza-virus-coinfection.80573/


Small Fiber Neuropathy associated to Posterior Cingulate Cortex atrophy in HIV
https://forums.phoenixrising.me/thr...terior-cingulate-cortex-atrophy-in-hiv.80657/
 

sometexan84

Senior Member
Messages
1,229
Well, how about that...

Time for me to get to work on my Small Fiber Neuropathy research I guess...
1610741397804.png
 

sometexan84

Senior Member
Messages
1,229
Idk, right now I'm just like frantically researching what this means.

I've never had pain. My symptoms that fit this include....
  • Fatigue and sleep abnormalities (+sympathetic, -parasympathetic)
  • Bladder control (very frequent urination)
  • Numbness (hands and legs)
  • Cold feet
  • Excessive sweating
  • Rapid and irregular heartbeat
  • Constipation and diarrhea
  • Orthostatic hypotension
+ all my other autoimmune issues I've had... it looks like whatever the Autonomic, Immune-mediated version of this is.

TS-HDS (Trisulfated heparin disaccharide IdoA2SGlcNS-6S)

loss of peripheral autonomic nerve fibers

small fiber loss with IgM deposits around the outside of medium- & larger-sized capillaries with C5b-9 complement deposits

more than 1/3 of SFN patients have TS-HDS autoantibodies, and that 92 percent of people with acute-onset SFN have these antibodies
 
Messages
78
Location
SF Bay Area
Sometexan84 did you ever have a skin biopsy done? That's how I learned about my small fiber neuropathy. The symptoms I have are pins and needles in my hands and feet, body aches, cold feet, frequent urination and a menthol cooling sensation on my skin. My autonomic nerve fibers are probably involved too because my hr sometimes becomes elevated upon standing.
 

sometexan84

Senior Member
Messages
1,229
Not yet. My symptoms haven't been super extreme. Though I have had the cold feet and frequent urination.

I'm peeing like 10 times a day. Is that too much?
 
Messages
78
Location
SF Bay Area
I'm not sure if that's too much. It could depend on how much water you drink. When my feet become cold they stay that way for a while despite blankets and socks. Is that the same for you?
 

sometexan84

Senior Member
Messages
1,229
Yea, and I'll sometimes put on 3 pairs of socks, lol.

And when I'm in bed w/ my kids, I'll put my feet under their legs to absorb their body heat. :thumbsup: