Thursday, August 26, 2010

Severe Drug Reaction? New Finding - It Might Actually be an Immune Response

A type of drug reaction called Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) most frequently happens when a patient is taking antibiotics and/or anti-epileptic (anti-seizure) medications. Several other drugs have also been implicated in DRESS. Until now, the reason why this type of reaction occurs was completely unknown.

A recent article in the journal Science Translational Medicine says Scientists have found that DRESS (also known as Drug-Induced Hypersensitivity Syndrome (DIHS) is actually the result of an immune response to a reactivated virus, most often a herpes virus. In DRESS, the body's immune cells (fighter T cells) go into overdrive to fight the reactivated virus, causing the elevated number of eosinophils found in routine blood work.

The disorder can look like autoimmune disease, but the T cells aren't actually attacking self, they are actually attacking the virus.

Symptoms of DRESS include:

High fever
Skin rash
Organ inflammation including liver, kidney, lungs and heart

About one in 8000 persons taking these medicines get DRESS. DRESS is fatal in about 10% of the population that gets it.

How does this work?

Herpes is a virus. When a patient gets a herpes virus (there are many possible variants) the body is able to fight it off, but instead of killing the virus, it goes dormant. These viruses can reappear later in extremely mild to extremely severe situations.

Chicken pox is a common virus that works in this manner. You get sick, body fights off the virus, virus goes dormant hiding in cells, virus reappears when immune system is low and we call it another name: Shingles.

In this case, the medications actually cause a reactivation of the virus living dormant in our cells. This results in the body's immune response and the attack on organs errrr... the virus.

What is eosinophilia?

Eosinophilia is an uncommon problem, but if you look at the side effects of many drugs taken by Migraineurs and chronic pain patients as preventatives and pain treatments, you'll notice that eosinophilia is often listed.

Eosinophils are cells that are present in extremely low numbers in the blood system. When a white cell manual differential is performed (a special blood test that looks at and counts each individual type of white blood cell), you can expect numbers to range from 1 - 4%. Eosinophils' job is to aid in the destruction of phagotocytized cells. An increased number of eosinophils is called Eosinophilia and it is a very uncommon condition. Eosinophilia most often occurs in severe allergic reactions and parasitic infections. A type of leukemia can also present itself with increased eosinophils, as can some autoimmune disorders. Taking the supplement L-Tryptophan can also cause eosinophilia as a part of the disorder Eosinohilia-Myalgia Syndrome (EMS).

Eosinophilia that occurs for a very short period of time is not likely to cause serious damage, however long lasting eosinophilia is dangerous because the eosinophils accumulate in tissue and vital organs.

Treatment for DRESS

Treatment for eosinophilia consists of corticosteroids, but in DRESS is controversial The treatment for DRESS is much less defined. It is suggested that anti-herpes drugs may be beneficial, but this is all very new, and as of yet no research has been done to either prove or disprove this assumption. Certainly lowering or ceasing the drugs causing DRESS is warranted, but often leaves the patient needing other medications for their pre-existing medical conditions.

My story

About two years ago, while undergoing therapies that included multiple drugs that can cause DRESS, I suddenly acquired eosinophilia. I was asked about an allergic reaction (none) and whether I took L-Tryptophan (no) and immediately tested for parasites (so much fun). Everything came up negative. An additional test was done to confirm the eosinophilia (still elevated) and I was referred to a Hematologist (blood doctor) for evaluation for Eosinophilic Leukemia and another confirmation of eosinophilia (yes it was still there).

The genetic blood test (one single test) that I had cost me in excess of $5,000.00 and showed I did not have the marker for cancer. I stopped or lowered the medicines that I (not my doctors) found could cause eosinophilia. In the meantime I had another appt with another doctor who diagnosed me with Trigeminal Neuralgia (Tic Doloreaux or TN) which he suspected could be related to a hidden case of shingles (not an infrequent occurrence), and I was prescribed anti-herpetic medicines to try. At the same time a deficiency of vitamin B12 was discovered and I began supplementation. My TN disappeared as did my eosinophilia, and my intractable Migraines nearly disappeared. I had not felt so good in many years, but it was short-lived. My hematologist dismissed me and my neurologist thought my success was all because of the B12 supplementation, so I quit the anti-herpetic.

Learning about this reaction now, I can't help but wonder if my strange case of eosinophilia may have been more than any of us thought. Then again, maybe it was just a fluke. Since that time I have taken great care to be sure that I take the bare minimum of any meds that could cause a recurrence of my eosinophilia. I can't get away from one of them, but the others I have stopped entirely - with my doctor's help, if not their approval.

I will be taking this information to my doctor on my next visit, and we'll see if perhaps another trial of anti-herpetic medicines might be in store...

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