Sunday, October 25, 2009

A New Miracle Drug for Peripheral Neuropathy, IVIG

In a prior blog below I described my initial experience with peripheral neuropathy (pn), its onset 25 years ago, noticing numbness and tingling (n & t) in the soles of both feet, then a quiescent period with no progress in symptoms for 15 years, after which I noticed onset of n & t in the fingers of both hands, then another quiescent period with no progress in symptoms for 8 years and finally noticing an increase in the n & t in January 2009 and now associated with onset of poorer balance and an unsteady gait.

Early investigation, a nerve conduction study (ncs), was normal and no known cause of the condition was found. No repeat study was done until this year,2009, when a repeat of this study revealed degeneration of the myelin sheath covering the distal nerves as well as axonal degeneration of the nerve fibers themselves in all four extremities.

While earlier studies revealed no known cause for the pn, research since then has discovered other causes of pn. In my case, it is due to a Gammopathy, an autoimmune disease. My body has, for unknown reasons, produced antibodies of the IgA, IgG and IgM variety which are attacking my peripheral nerves, destroying both the myelin sheath covering the nerves as well as the nerve fibers themselves. This obviously has been a slow process as attested to by the long periods of quiescence. However, one neurologist explained that the process begins in the most distal nerves, in the feet, and doesn’t appear in the upper extremities until later because these nerve fibers are shorter but when the distance in the affected lower extremity fibers equals that of the upper extremities it then appears in the fingers, ultimately progressing upward in all 4 extremities. I get the impression that there are subsets of the condition and it may at times be inactive as far as progression is concerned. One type, Chronic Inflammatory peripheral neuropathy, has an inflammatory component, as the name implies, which makes it more amenable to treatment with anti-inflammatory agents.

Gammopathy for most people is a benign condition, a laboratory finding with no sequela. However, 1% of affected persons per year will develop a serious complication in the form of a lymphoma, multiple myeloma, amyloidosis or Waldenstrom’s Macroglobulinema. Ten percent will develop a pn which is where I fall.

Fortunately, treatment for this pn is available. I was initially treated with Retuxin, an infusion of this drug over a 5 day period. I was told that there was about a 50% chance that it would work. Unfortunately, I was in the wrong 50%. At that time I was devastated and it seemed that this disease would progress to the point that I would be unable to walk in the not too distant future.

Then I was offered another drug, ivig, intravascular immunoglobulin. Another doc then said that I was not a candidate for this drug because my B lymphocyte count was too high. After 6 months of “wrangling,” it was decided that I was a candidate, this count, after all, was not too high. So, in the latter part of September 2009 I received a 5 day infusion of the ivig which was innocuous. I was told that it would take anywhere from 1 to 4 weeks to see if the drug worked. Almost miraculously, 9 days after the infusion, I noticed a significant lessening of the n & t in both my feet and hands. I estimate that my symptoms lessened by 50% over a 3 – 4 week time period. Less apparent was improvement in my balance and gait which I think is perhaps 10 – 20% better,

That’s the good news. The bad news is that the drug is only effective for 3 – 4 weeks. However, this is not so bad because I can receive the drug monthly for the rest of my life. Presently, I have received a second infusion, the 5 day dose now being given in 2 days. This will continue monthly for 3 months at which time we will reassess my progress; symptoms and signs, neurological exam and lab studies, the latter to see if the “bad” immunoglobulins have decreased.

If the ivig will keep my pn from progressing for the rest of my life, the monthly infusions are a small price to pay. Will a return to running and skiing be in my future?

Thank God for Medicare. I hope the new health care bill doesn’t take away this type treatment for us “olde folk.”