Idiopathic Neuropathy

 Today's post from neuropathy.org (see link below) talks about what happens when you are diagnosed with Idiopathic neuropathy. 'Diagnosed' is not quite the right word because idiopathic neuropathy is the conclusion reached when other forms are ruled out, or the doctor can't establish a definitive cause for your problems. You then go away feeling slightly cheated and maybe even not believed but the fact is that between 20% and 50% of people with neuropathy are diagnosed as being idiopathic. It really just shows how limited the testing procedures still are in the field of neurology/neuropathy. Many people, for instance, can point to chemotherapy, or diabetes, or HIV as logical causes for their neuropathy but it's by no means an exact science. Even if one cause seems obvious; with over 100 possible causes and over 100 forms of neuropathy, you may have combinations, or the one you thought may only be a co-morbidity with something else. Testing will need to improve as numbers continue to grow but you should always remember that an idiopathic diagnosis does not lessen your symptoms or validity in any way.
 

 

 
You’ve Been Given An “Idiopathic” Neuropathy Diagnosis. What’s Next?
By Shanna K. Patterson, MD

The term idiopathic neuropathy means that the cause of neuropathy is not known.

Unfortunately, this label currently applies to approximately 20% of patients with neuropathy, and up to 50% of patients with small fiber neuropathy. This can be a source of great frustration for both patients and neurologists.

Naturally, many patients with idiopathic neuropathy ask, “Is there anything else that can be done to search for the cause of my neuropathy?” The answer depends on the details of each person’s case. For some patients who have been given an idiopathic neuropathy diagnosis, the answer may be “yes.”

Here are a couple questions to think about when deciding whether to discuss this question further with your physician:

1. How long has it been since you underwent testing for potential causes of neuropathy?

• Repeat testing can be informative if a slowly developing or mild condition was previously below the threshold for detection.

• New genetic testing may be available, and could be appropriate in some cases.

• While there is no official recommended time interval when testing should be repeated, raise the possibility of repeating tests if neuropathy symptoms are significant, progressing, or several years have passed since the initial work-up was done.

2. Have you been evaluated by a neuropathy specialist?
Most commonly, physicians think about diabetes, thyroid dysfunction, and certain nutritional deficiencies as causes for neuropathy. However, a neuropathy specialist—neurologists with a focus on neuromuscular diseases such as neuropathy—may be able to determine the underlying cause for some patients who have been given an idiopathic neuropathy diagnosis. In some cases additional detailed history, additional testing, or other analysis of the existing information for an individual patient could be helpful:

• A neuropathy specialist may be able to recognize how certain known medical conditions could be causing neuropathy. For example, kidney or liver diseases, past gastric bypass surgery (which can lead to nutritional deficiencies), or certain rheumatologic disorders can be associated with neuropathy.

• A neuropathy specialist may be able to reveal the underlying cause of neuropathy by taking a more detailed history. For example, asking about past and current medication use can reveal the cause of neuropathy. Medications such as statins (a class of medications used to treat high cholesterol), certain types of chemotherapy, immunosuppressants, and certain HIV medications can cause neuropathy. Also, discussing possible toxic exposures, such as heavy metals or environmental toxins, can be useful in some cases.

• Diabetes is a well recognized and common cause of neuropathy. However, neuropathy can be caused by a milder form of elevated blood sugar levels, known as glucose intolerance. Essentially, this is when blood sugar levels are higher than normal but below the cutoff to diagnose diabetes. Early recognition and treatment of this condition can lead to improvement in neuropathy in some cases.

• A neuropathy specialist may consider testing for less common causes of neuropathy, such as autoimmune or hereditary conditions, when appropriate.

In conclusion, idiopathic neuropathy can seem like a hopeless situation—an incomplete diagnosis—and for these patients symptom management is key. It is important to remember that for some patients, further evaluation by a neuropathy specialist can help determine the underlying cause of neuropathy. This can guide treatment choices, and lead to eventual symptom improvement. For some patients the underlying cause of neuropathy may not be evident even after further evaluation, but on-going research helps us to learn more about neuropathy’s various causes, develop new tests, and consider new treatment approaches for neuropathy. If your neuropathy symptoms are persistent, a cause of significant distress, or steadily worsening, then partnering with a neurologist with experience in evaluating neuropathy can be worthwhile.

http://www.neuropathy.org/site/News2?page=NewsArticle&id=8269

Life With Idiopathic Neuropathy

 Sometimes a personal account has far more impact than a scientific article with no personal appeal and that's the case with today's post from livingwithperipheralneuropathy.blogspot.com (see link below). There's no suggestion that the author has any connection with HIV but her account will certainly strike a chord with many people with neuropathic problems. Just knowing that someone else is going through the same as you can be a great comfort.

 

Living with Peripheral Neuropathy
Sunday, January 8, 2012 by Betsy

I've looked online quite a bit, and find that although there are tons and tons of pages out there that give drug review info, there really isn't anything that gives real life, valid info on Peripheral Neuropathy. There's no place for people to go to discuss how it feels to have to live in chronic pain with this debilitating condition. So I decided to start this blog in the hopes that others might find their way here and share their stories to help those who are newly diagnosed. It's a scary thing to face when it's brand new to you.

My name is Betsy. I was officially diagnosed in May of 2011 with "idiopathic" peripheral neuropathy. That means there is no known cause. The only possible cause in my case, but not confirmed, is that I took too many mega B vitamins over a period of 15 years or so, leading to a toxic level of vitamin B6 in my bloodstream. Apparently, that can cause neuropathy. So much for trying to take care of myself!

I started having symptoms LONG before I saw a doctor about it; it was only in hindsight that I was able to recognize them as early onset symptoms. I finally saw a doctor when the burning pain in my hands and feet became too much to bear. I thought it was arthritis. The doctor said, "It's neuropathy," and sent me to a neurologist where I was ultimately diagnosed.

My symptoms when I sought treatment were severe: My hands and feet would swell up and I was losing strength in my hands, unable to do normal tasks without great difficulty. For example, I have long hair, and holding a hairbrush hurt a great deal. I was having trouble cutting my meat up on my dinner plate. It hurt to use utensils. I could no longer peel a potato without great pain.

My feet burned with fire from within - BURNING PAIN. That was/is the only way to describe how it feels for me. I know for others, neuropathy brings a lack of sensation, a numbness or tingling. I almost wish it was that way for me. It got to the point where I wanted to literally chop my feet off at the ankles, because it seemed like that would be the ONLY way to make the burning pain STOP. Obviously, that is not even logical.

At night, the pain would either keep me awake, or wake me from a sound sleep. My hands would be swollen claws. I had to lie in a way that my feet wouldn't touch ANYTHING, not a sheet, not the mattress, not each other - they could touch nothing but air. I was eating ibuprofen like it was going out of style - and while it helped the swelling, it did nothing for the pain. I had to find a way to get this treated. It was affecting my job, my sleep, my life.

I had to wait 3 months before I could get in to see the neurologist. In the meantime, I researched my butt off, learning all that I could about "neuropathy." I self-diagnosed it as "peripheral neuropathy," and learned enough about it to scare the crap out of me. (I am one of those that tends to plan for the worst but hope for the best. The worst case scenarios for this condition are terrifying, but they are potential reality.)

My hands are starting to hurt too much to continue typing, so I'm going to stop here for now. I will pick up again later. Eventually I plan to publish helpful links for people that are learning to live with this as I am. I welcome any and all comments from people that have been/are now living with Peripheral Neuropathy, regardless of the cause. Please feel free to add links that you think might be helpful to others that are dealing with this chronic pain.
 
http://livingwithperipheralneuropathy.blogspot.nl/2012/01/living-with-peripheral-neuropathy.html

Idiopathic Neuropathy unmasked

You know the feeling, the doctor has just informed you that your particular form of neuropathy is called Idiopathic, because they can only find minimal evidence via the testing procedure. It is acknowledged that you're suffering from neuropathy (there's no other pain or sensation (or lack of) like it) but you still walk away feeling slightly cheated and perhaps with the feeling that you've not been believed. Illness needs to be confirmed by medical testing - according to the way we've been brought up - otherwise, it must lie somewhere between your ears! Every misdiagnosed patient's nightmare! Well, today's post may just give you the evidence you need to change the description, 'idiopathic', or at least a reason for further investigation. It comes from ScienceDaily.com (see link below) and is recent research, having come out in June of this year.

Source of Mystery Pain Uncovered
ScienceDaily (June 22, 2011)

An estimated 20 million people in the United States suffer from peripheral neuropathy, marked by the degeneration of nerves and in some cases severe pain. There is no good treatment for the disorder and doctors can find no apparent cause in one of every three cases.

An international team of scientists headed by researchers from Yale University, the Veterans Affairs Medical Center in West Haven and the University Maastricht in the Netherlands found that mutations of a single gene are linked to 30 percent of cases of unexplained neuropathy. The findings, published online June 22 in the Annals of Neurology, could lead to desperately needed pain treatments for victims of this debilitating disorder.

"For millions of people, the origin of this intense pain has been a frustrating mystery," said Stephen Waxman, the Bridget Marie Flaherty Professor of Neurology and professor of neurobiology and of pharmacology and a senior co-author of the paper. "All of us were surprised to find that these mutations occur in so many patients with neuropathy with unknown cause."

The study focused upon mutations of a single gene -- SCNA9 -- which is expressed in sensory nerve fibers. Waxman's group had discovered that mutations in this gene's product -- the protein sodium channel Nav1.7 -- cause a rare disorder called "Man on Fire Syndrome," characterized by excruciating and unrelenting pain. Colleagues in the Netherlands carefully scrutinized neuropathy patients to rule out all known causes of the neuropathy, such as diabetes, alcoholism, metabolic disorders and exposure to toxins. Researchers then did a genetic analysis of 28 patients with neuropathy with no known cause. They found 30 percent of these subjects had mutations in the SCN9A gene. The researchers found that the mutations cause nerve cells to become hyperactive, a change they believe eventually leads to degeneration of nerve fibers.

"These findings will help us as clinicians to a better understanding of our patients with small fiber neuropathy and could ideally have implications for the development of future specific therapies," said Catharina G. Faber, who is a lead author of the study along with Ingemar Merkies of the Netherlands.

Other Yale authors of the paper are Hye-Sook Ahn, Chongyang, Han, Xiaoyang Cheng, Jin-Sung Choi, Mark Estacion and Sulayman Dib-Hajj.

The research was funded by the Department of Veterans Affairs, The Erythromelalgia Association (USA) and by the Profileringsfonds of University of Maastricht, The Netherlands.

http://www.sciencedaily.com/releases/2011/06/110622125656.htm

Idiopathic Neuropathy A Worrying Diagnosis

Today's post from kevinmd.com (see link below) talks about idiopathic neuropathy which is basically neuropathy for which no clear cause can be found. Many people with neuropathy symptoms go to their doctors, undergo a series of tests (also outlined below) and although the diagnosis of neuropathy is made, the tests don't reveal what caused it. This is hardly surprising when there are more than 100 possible causes of nerve damage and many people have more than one condition that may be responsible for their symptoms. A diagnosis of idiopathic neuropathy can be very unsatisfying and worrying for a patient, especially if they feel that they're perhaps not being believed or taken seriously but it is a genuine diagnosis and takes nothing away from the fact that you have neuropathy - it's just they can't positively identify the cause.

Idiopathic neuropathy: 2 steps providers can take

SHANNA K. PATTERSON, MD | FEBRUARY 10, 2013

It is estimated that over 20 million Americans have neuropathy. Many people don’t know that prior to the advent of the obesity pandemic and the associated rising rates of diabetes, leprosy was the most common cause of neuropathy worldwide. Although it is now widely recognized that diabetes is the most common cause of neuropathy, for up to 30% of patients the cause of their neuropathy remains unknown. These cases are dubbed “idiopathic,” and – as a neuropathy specialist I assure you – that for many patients this becomes a chronic source of frustration and anxiety.

Some of the questions I hear from idiopathic neuropathy patients include:

What are the chances my neuropathy will get worse?
Isn’t there any treatment?
What else can be done to find the cause of my neuropathy?

It is almost impossible to address these issues without a more specific neuropathy diagnosis.

Diagnosing neuropathy is a two-step process. First, the diagnosis of neuropathy is confirmed. This should include identifying the population of nerves involved, the type of nerve pathology, and the distribution of nerve pathology. Detailed electrodiagnostic testing (electromyography and nerve conduction studies), and possibly a skin biopsy (to detect the involvement of small fiber nerves) or autonomic testing (to detect the involvement of autonomic nerves) may be required. Second, the cause for the neuropathy can be explored, starting with blood tests. In some cases a nerve biopsy or genetic testing may be needed. The more specific the characterization of the neuropathy, the easier it is to know how to look for what might be causing it.

I would argue that for any idiopathic neuropathy patient whose symptoms affect daily activities – whether that is because of pain, weakness, imbalance, or difficulty walking – further steps should be taken to help search for a more specific diagnosis.

Two steps that every health care provider can take include:

Making sure your patient is seen by a neuropathy specialist. A neuropathy (or neuromuscular) specialist is a sub-specialized neurologist. These clinicians can sometimes uncover less common causes of neuropathy such as hereditary, toxic, autoimmune, and paraneoplastic etiologies. They can also more readily discern when a patient might have a more unusual presentation of a common form of neuropathy.

Asking how long it has been since your patient had a neuropathy evaluation. In cases where patients were evaluated for neuropathy a number of years ago, a referral for a repeat evaluation can help determine the underlying cause of neuropathy and guide treatment choices. In some cases the underlying cause of neuropathy may not be evident even after further evaluation, but on-going research helps us to learn more about neuropathy’s various causes, develop new tests, and consider new treatment approaches. Also, for some patients, interval electrodiagnostic testing can help clarify the diagnosis, especially if the neuropathy is progressing.

Hopefully these points can help idiopathic neuropathy patients obtain the clarity they seek and the medical care they need.

Shanna K. Patterson is a neurologist and serves on The Neuropathy Association’s Medical Advisory Committee.
http://www.kevinmd.com/blog/2013/02/idiopathic-neuropathy-2-steps-providers.html