question about small fiber neuropathy diagnosis
 

Hi, I'm new to the board. I have two questions which are somewhat interelated.

Question 1 - I've been diagnosed with idopathic small fiber sensory neuropathy, but I'm looking to get a second opinion. I live in Southern California, Orange County. One thought is to go to either UCLA or Cedars Sinai, does anyone know any specific doctor at those two places, or are there any other good neuro's that you recommend?

Question 2- Background first - I am 46 6-0 175 lbs and in very good health. About 3.5 - 4 months ago I started to get tingling fingers while sleeping, didn't think much of it. Then on Sept 20, I woke up in the night with tingling/numbness up the arms, and a little in the feet/legs. This concerned me greatly. I became very anxious after this. Went to the Nuero Doctor and after having all kinds of test (i.e typical blood work for this issue, Autoinmue blood work, Cat Scan of brain, MRI of head/spine with and without contrast, MRI of lumbar, Nerve studies) all negative.

Based on this, and based on my symptoms, Neuro Doctor diagnosed me with SFSN. For the last two month I've been taking 2- 75mg lyrica pills at night, and 1- 25 mg Amitriptyline, also before bed.

However, I don't believe my symptoms are all that similar to SFSN and my Neuro Doctor didn't think that I should have skin biopsy to confirm this diagnoisis, he didn't think they were all that accurate.

Here are my symptoms - Whenever I try and sleep, whether it is day or night, just as I am starting to fall asleep, I start to get tingling/numbness starting in my hands and then arms, and to a lessor extent in my legs. Many times this will wake me up but when I move, those tingling/numb feelings go right away, and I start the proceess all over. On good nights I can get back to sleep and stay asleep, the sedation of the medicine has help with this.

On bad nights, I will be awaken by this, and for some reason when I'm awaken, I am startled and my heart is racing, and then I will start to get a burning feeling up my arms. As I calm down and start to go back to sleep, I will start to get this tingling burning feeling up my arms and into my scalp and one side of my face, it will also creep up my legs and into my back. If I sit there for a while the burning will dimish some, and I will be able to sleep for a while, but will be awaken again a 1/2 to hour later, and start the process over.

Anyhow, I feel like there may be a anxiety and/or sleep issue component to this. During the day I don't have any symptoms, except for the exhaustion and emotional instabilty caused by the bad night, along with a little tingling at times. So my 2nd question is, does this sound like SFSN or something else.

Sorry to be so long winded, but any comments on these two questions would be appreciated.

thanks, Fogger

Small fiber neuropathy is a symptom. When it is termed idiopathic, it means they have found no 'cause' for your SFN. Often times, SFN is related to diseases. Many people on this forum have diseases that are associated with or potentially are the causes of their SNF. Others of us, are the 'idiopathic' ones.

Idiopathic is a diagnosis arrived at when every other disease that causes SFN is ruled out. It is a diagnosis of exclusion.

I think there is a thread Neuropathy Basics or something like that. Neuropathy 101 is what it is.

You are correct to question the medication of just your neuropathy, without the docs having explored the causes. Getting to the cause may take years, and even after years of testing you may remain, 'idiopathic' for the time being.

There are conditions where neuropathy precedes the onset of other diseases by years.

Check out neuro.wustl.....I can't give you the exact web address but it come up on a search.
There are hundreds of reasons for small fiber neuropathy, and most of us feel those should be ruled out prior to calling it idiopathic.

Good luck with your searching.

Here you go:

http://jnnp.bmj.com/cgi/content/full/74/1/93

At least I think it's what you're referring to!!

mel

Also, check out the LizaJane spread sheets to make sure you have had the tests done that are on there.....remember, no doc is going to just submit you to a huge battery of tests all at once. This takes time...

Also, don't attribute the heart racing to emotional symtoms too quickly...you will find that docs may be willing to write that symptom off as emotional way too quickly and then diagnositic tests become more of a battle.

You may be having emotional distress due to neurological imbalances, and you may be having emotional distress due to the diagnosis, or you may have dysautonomia which can result from small fiber dysfunction. Dysautonomia can feel emotional.

Small fiber neuropathy can cause autonomic neuropathy which causes havoc with blood pressure and heart rates. A sleep study might be helpful as your symptoms seem to come on at night. I would be very curious to see what that yields.

I personally do not believe in medicating symptoms until you have found a cause, or at least ruled out causes and have no choice but to medicate symptoms. Others may disagree.

There are disease entities out there in which some drugs are absoulute contraindications. Besides looking at the spread sheets and neuro.wustl site explore your family history....not just immediate family, but out to second cousins etc.

One of the mainstays out there, amitriptyline is contraindicated in my type of neuropathy, so are SSRIs. Take time and find out what is going on, and also, some of this stuff comes and goes....and many of us here on this forum have lived with this for decades, and we are still kicking. Hang in there.

thanks for the replys so far. A couple more questions.

First, Cyelops, what kind of Doctor would perform a sleep study?

Second, As I mentioned in my original post, do you think that getting a Skin Biopsy test is a good way to determine if I in fact have Small Fiber Neuroapthy? Or is that test, as my Neuro Doctor stated, not reliable.


thanks

Hi and welcome to this forum Fogger, i am wondering if you have had a B12 test yet, as low levels can cause numbness and tingling, this site has been made by our B12 expert, Rose, it's well worth reading.
http://roseannster.googlepages.com/home
Also wondering if that neuro sent you for Quanitive Sensory testing. http://www.hmc.psu.edu/healthinfo/pq/qst.htm, usually done before any skin punch is considered.
good luck
Brian :)

Hi Fogger,

I read your comment that your doctor didn't think a skin biopsy test was reliable and I just scratched my head since that was the main test my doctor used to confirm my peripheral neuropathy. He didn't have the test three years ago, when I first saw him, so maybe your doctor is operating off of old info. Or maybe there are less reliable skin biopsy tests out there -- my doc said that this lab (Therapath) was one of the only labs that did this test using their particular methodology.

If you can get it printed it out and give it to him, you can find an example of the pathology that they're looking at by going to Therapath dot com, click on 'For Physicians' and then 'Interpretation of Results'. (The board software doesn't trust me to post links yet.) You can find some abstracts on the research (though they all involve relatively small groups of people) by then clicking on 'Abstracts'.

With your symptoms, I also wouldn't be too eager to assume its an anxiety reaction to the SFSN. It could be, but it could also be due to some other cause, or a reaction to one of the medications you're on. You might ask about switching meds, or going off them for a period of time if you can stand it. The sleep study idea is good, too.

Hang in there, having your sleep interrupted like that sounds so uncomfortable!

There are other tests--
 

--that can be useful to diagnose small-fiber syndromes, such as quantitative (thermal) sensory testing and various autonomic tests (many autonomic functions are controlled by the small fibers, and people with small-fiber conditions often have disruptions in sweating, blood pressure with postural changes, and the like), but the skin biopsy is the current gold standard. It was the only test for me that was unequivocally abnormal--I had 2% of normal intraepidermal small fiber density with my first one (I've had others later to track my case--I was up to 11% on my last one--but I am unusual in that I had an acute onset body-wide burning neuropathy that seems to have been monophasic and is slowly resolving over years, though it's doubtful I'll get full recovery).

A small-fiber neuropathy cannot be ruled out if the skin biopsy is normal--but normal is usually defined as falling between the fifht and ninety-fifth percentile of intraepidermal small fiber density (as designated by the original norming process researched at Johns Hopkins). One can fall into that rnage and still show abnormal branching, swelling, or other morphological changes that are suggestive of small-fiber neuropathy.

The problem is that the pathologists trained in deciphering this are few and far between--it's why skin biopsy is only done at a small number of centers, though Hopkins has a program whereby a physician can send in skin samples to be analyzed there. Moreover, rarely will even an abnormal skin biopsy point to a cause of the neuropathy. But if the biopsy is abnormal that's pretty much a slam-dunk that you've got small-fiber involvement.

Have you been evaluated
 

for Arnold Chiari Malformation? An MRI of the upper neck will reveal this. Sometimes it is a mild presentation, and has to be looked for.

Hands that tingle and go numb at night might be due to carpal tunnel. Have you tried wearing braces on your wrists to hold them so they don't pinch the tunnel?

Often carpal tunnel starts at night like you are having it.

Do you have puffiness in the hands? Swelling? Do you consume alot of salt?

Are you a male? You didn't say in your post. If you are male, do you use vibrating tools?

Do you drink alcohol?

Another thing to try is the gluten free diet. Some people present with neuropathy when gluten intolerant. Keep a food diary and see if your spells at night follow a rhythm ... worse with certain types of food. Some foods release histamine-- and this causes alot of tingling for some people.
If you suspect a food trigger... do an elimination diet. Remove that food for
at least 2 weeks.

Also you can try Thiamine to see if you have problems with low thiamine. This can be genetic or induced by heavy alcohol consumption. 200mg -300mg of this daily may improve nerve functions. If you suspect a food trigger/histamine release, you can try the AlkaSeltzer treatment. Use regular with aspirin AlkaSeltzer before going to bed. That is if you can tolerate aspirin and don't have other drugs that will add or interact (Coumadin, Plavix, Pletal, etc)

The fact that you only have symptoms at night is telling you something.
Position, food for dinner, alcohol at night, etc. Do you have allergies? It might help to get a new pillow, in case you are allergic to bed mites. (things like that) Some people are allergic to feathers and don't know it, for example.

A sleep study may help. It will show if you are having problems in the brain stem..for example. However, sleep paralysis does not typically have pain associated with it.

There are docs that specialize in sleep studies, it can be a neuro, a pulmonologist...look for a place that has a sleep study program. You have a lot going on. I assume you are an active healthy person, suddenly hit with perplexing symptoms, and it is disconcerting. Diagnosis can take years as the docs follow algorithims and sometimes hunches. I would be curious to see if there is something going on at night that is causing this....it is an easy test and might yield some info.

Skin biopsies are gold standard at this time for small fiber neuropathy. I recently read that muscle biopsies should also be done with that...but that is a much bigger deal, is surgical and I don't see docs jumping to that too quickly...quite invasive.

You are far from being idiopathic at this point.