Metronidazole induced SFN
 

Hi there,

I just wanted some advice from you peeps.

I have been diagnosed with SFN through skin punch biopsy by a prof in London.

He wrote to me advising that my skin biopsy showed my nerves were re-generating too much and noted it is in contrast to diseases like diabetes were there is a loss of nerve fibers.

When i have read online i can't find much about this, from my understanding it says there is a loss of nerve fibers with most SFN

I have SFN all over, i took Metronidazole twice in November and December 2012, and i noticed symptoms starting on New Years Day 2013. The prof noted that my skin biopsy is in keeping with a drug induced neuropathy/chemo induced (i haven't had chemo). He also noted it was in keeping with neuroinflammation or an autoimmune disease. I have had a full work up including lumber punch which has all come back normal so far. I am having a lip biopsy for sjogens in a few months.

I am 37 this started a few years ago with odd sensations all over my body. i didn't get any burning until i was told it could be SFN, the neuro said the anxiety had brought it all out

So the prof suggested it could be the metronidazole, he said the first case was reported in 1976, but he said i needed to be fully checked first which i am.

So does anybody think this could have been the drug? I am hoping this was the cause as the neuro suggested it won't get worse, but she also said it won't get better even if it is that.

Hi LouLou,
I'm awake and online and saw your message.

I just wanted to suggest that you could search this PN forum and the subforum PN Tips, Resources, Supplements & Treatments

http://neurotalk.psychcentral.com/search.php

You will find posts about neuropathy and Flagyl / Metronidazole. Try both names Metronidazole and Flagyl.

thank you for that, I will have alook. I haven't read much about metronidazole causing non-length dependent neuropathy though. Also I don't know if anybody has heard of a skin biopsy showing too much re-generating of nerves?

First time
 

I am not familiar with a large cross-section of biopsy results but this is the first time I have heard about accelerated regeneration. Quite the contrary. hope your symptoms will improve at a comparative fast rate also. Good Luck, Ken in Texas.

Glenntaj is the one to consult. I seem to recall his saying that
the skin punch biopsies will show regeneration (the cells are immature etc)...

But really "too much"...that seems a bit unbelieveable. I think patients are lucky to get "any" regeneration"... but too much? This too much seems unrealistic to me.

When my hypothyroid issue was corrected, I remember my numb feet (they first were very painful, then became mostly numb)...
"woke up" and tingled and burned for just about a year as they
improved from my thyroid hormone. So yes, sensation may return and feel pretty bad as things fix themselves, but "too much"? I have never seen that posted here by anyone.

Hi there,

Thank you for the replies,

maybe I haven't explained this properly so ill read the letter from proff

"We proceeded to skin biopsy of the calf which showed a clear increase of intra-epidermal fibers with the gold standard structural marker pgp9.5 at 11 fibers/mm the normal range being 6.5. Other intra-epidermal markers were similary increased, including GAP43 which is a marker for regenerating fibers 3.1 fibres. the normal range being 1fibre/mm. This is in contrast to conditions such as diabetic neuropathy where there is a loss of intra-epidermal nerve fibers.

The skin biopsy findings are in keeping with neuroinflammation or autoimmune conditions and can be seen in patients who have had drug treatments or chemotherapy" He goes on to suggest this is seen in sjogens syndrome and said voltage gated potassium channels can also cause this.

does this make more sense as it makes none to me! trust me to be different.!!?

Is this your second biopsy results? Did you have a test before this one? Or is he comparing your results to a "norm" that they use? Glenn has stated many times here that the biopsy itself is
only an estimate and that people vary...some have more fibers to start with than others, etc.

Send glenntaj a PM and ask him. He is very knowledgeable.

Hi Mrs D,

No this is the first biopsy I've had. He is just comparing my biopsy to normal people of my age.

I don't really understand. When I asked the neuro she said it can go either way but I've never heard of them re-generating too much.

It just gets more frustrating and worrying.

Is Glenn a neurologist?

I don't know if glenn is a neurologist but from reading the site he seems to know his stuff.

I hope the results mean that maybe something irritated my nerves and my nerves are trying to sort themselves out.

Well, that's what i'm trying to tell myself and I am hoping and praying that they will one day.

thank you again everyone, you have all been very kind and helpful.

Loulouxx

There is some evidence--
 

--that increased intraepidermal nerve fiber density as measured through staining may represent an early phase of small-fiber damage, as the body attempts to fight the process through increased branchings. Of course, it may be hard to distinguish this in a skin-biopsy "snapshot" from nerve regeneration.

A good electron microscope analysis can often distinguish these increased branchings from regeneration by looking for evidence of fiber deterioration, notably in the form of fiber swellings. But one needs to have such things looked for, and by an experienced micro-pathologist.

Take a look at this, which sort of summarizes this obervational difficulty:


http://www.medscape.org/viewarticle/563262_5



Fortunately, skin biopsy, while it generally cannot reveal a cause for neuropathy, is reproducable over time, so density and condition of nerve fibers in the same body areas can be repeatedly sampled and often that is a better indicator if neuropathy is progressing, healing, or merely stable.

Thank you Glenn for that clarification, i couldn't click on the link though. Do you think it could be possible that the Metronidazole caused this? I took two lots just before onset of symptoms?

Metronidazole and its newer cousin have been shown to cause neuropathy:

from http://www.ncbi.nlm.nih.gov/pubmed/16901452

While it is considered by some to be reversible, it also causes lesions in the brain, and we have had some posters here where the peripheral neuropathy did not reverse. So it may be a trigger for those who are CMT candidates.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2963744/

Metronidazole shares some metabolic pathways with alcohol...so that it suggests use of Thiamine or benfotiamine may help with repair from it use.
The build up of aldehydes in the body may be causing the burning pain for some people.

Hi Lou Lou, I believe that we saw the same Professor for our skin biopsy. He said in advance of my test that there is the possibility that the nerves will be inflamed or affected by inflammation and will therefore show signs of 'splitting', he also used the words regeneration. I think he meant that if they are splitting they will appear to be regenerating as there will be more fibres due to the splitting of the original ones. So you aren't mad, this is exactly what he explained to me. It seems really feasible that there would be splitting and therfore more fibres as a result of that. Just hope that helps you with any treatment for the underlying cause.

Thank you Mrs D and Joanna, when I have looked up metronidazole it seems to be a length dependent thing for sfn,i haven't read anything about it being non-length dependent. also I only used it twice before symptom onset.

Metronidazole given after surgery
 

Thanks again Mrs D
Although I had some symptoms of PN prior to an emergency appendectomy in Oct 2014, I was wondering why it had suddenly increased and spread over my entire body since. Have just checked the medical notes from the surgery and found I was given Metronidazole while in hospital, (first time taking it). Yet another possible cause to mention to the neuro when I finally get an appt. With the amount of info I've learned from this site I'll need to be careful not to annoy the doctor - especially if he gives a diagnosis of idiopathic PN - which from what I've read here seems to be the answer they give when they either don't know or can't be bothered looking further.