- Drug-induced Vasculitis
- Chronic Pain
- Rare Disease Network
First, I will answer Ed's question, because it is an easy one. Vasculitis is a broad category that is defined by the presence of inflammation in and/or around blood vessels. The inflammation is seen by a pathologist when he/she examines the biopsy tissue microscopically. The doctor who is seeing the patient (who is not a pathologist) makes the decision to perform a biopsy based on clinical findings. These may include visible signs (rash or livedo reticularis) or may include laboratory findings (blood and protein in the urine).
Vasculitis can then be subdivided into categories based on the site of the lesions, the type of pathology that that pathologist observes, and the patient's symptoms. Many of these subdivision have eponymic names, based on the person who discovered the condition. Some examples of these are Takayasu's Arteritis, Wegener's Granulomatosus, and Kawasaki Disease. Other divisions of the vasculitis group may be based on the microscopic appearance (polyarteritis nodosa, micrtoscopic polyangiitis, Giant Cell arteritis).The Vasculitis Clinical Research Consortium, recently established by NIH, will include study of six forms of vasculitis: Polyarteritis Nodosa, Giant Cell Arteritis, Takayasu's Arteritis, Churg-Strauss Syndrome, Wegener's Granulomatosus, and Microscopic Polyangiitis.
I read the following in an article. Could you comment on it?
"Therapeutic agents from virtually every pharmacological class have been implicated in the development of drug-induced vasculitis."
YEP! Whether it's an antibiotic, an antipsychotic, a heart drug, a kidney drug, a liver drug, or an illegal drug, it might be the trigger for vasculitis.
It is VERY important to recognize that *ANY* drug is something that is going to modify your "normal" physiology. The plan is that the modification will be a benefit, but in some cases there is a detrimental side effect. These side effects can vary from one individual to another, and may depend on other medications (including herbal, vitamin and supplement treatments) that you are taking, so it is important to have your doctor look at EVERYTHING you are taking.
Is Strep a trigger for vasculitis?
Group A streptococci are one of several bacteria that we are looking at as possible triggers of vasculitis.Many patients report the memory of a bacterial or viral infection prior to the onset of vasculitis symptoms, so this is one of the reasons that we are studying thie link. Another reason is that the inflammation that accompanies infections can trigger the release of cellular factors that may be involved in damaging normal cells in the blood vessels.
The problem with trying to correlate infections with vasculitis is that infections are very common, but vasculitis is very rare. We have to be careful when we try to make such associations, because we could select dozens of infections, environmental exposures, drugs or behavioral factors that patients are exposed to before the onset of their disease. The challenge to us in research is to look at all of the possible interactions, and to try to decide if there is a positive association. It is a difficult and time-consuming task.If vasculitis were caused by Group A Streptococci alone, the association would have been made years ago. Intense research in the 1920's showed that Group A Strep was the cause of pharyngitis (strep throat), scarlet fever, rheumatic fever, puerperal sepsis, impetigo, and other skin infections.
Much research has been done on the bacteria (it is not a virus, as someone stated in an earlier post) in the past 85 years, and the only associations with vasculitis have been anecdotal. It would be great if we could show that Strep or another bacterium was the cause of vasculitis, because then we could produce a vaccine or antibiotic treatment that would eliminate vasculitis.We continue to look for the underlying CAUSE of vasculitis. Based on my experience, I think it is a series of events, which might be different for each patient.
Linda is correct. With certain strains of strep, the antibodies that your body makes will mop up the remaining strep antigens, but then the immune complexes of antigen and antibody tend to settle in the kidney. They are joined by a normal blood protein called complement, and this complex will induce inflammation. This process usually occurs within a few weeks after the acute scarlet fever, not years later.
The heart involvement is an entirely different mechanism of pathology, but again, this doesn't cause vasculitis. In the heart, the antibodies against strep bind to normal proteins on the heart valves. Then our inflammation-inducing protein, complement, joins the party, and we get inflammation of the heart valves. This leads to acute rheumatic fever (ARF) (I tell my students that it is a dog of a disease). The damage can become chronic, and this leads to heart murmur, and possible mitral insufficiency, but these sequelae do not have anything to do with vasculitis.
There are many anecdotal reports of strep being a trigger for vasculitis, but strep infections are so common that it might be a simple coincidence. As Linda points out, there are also genetic links with AI diseases, and there are no known genetic links for strep infections.
This is one that we actually do know. There is no genetic link here, except the genetics of the strep bacteria themselves. Certain strains of strep produce a protein called M protein. These strains of strep are the ones that are involved in glomerulonephitis. They are called nephritogenic (nephritis-causing) strains of strep.
The current thinking is that since the B cell can be an antigen processing cell, The B cell cooperates with helper T cells to become an antibody-producing cell, and the actual antibody-producing cell is called a plasma cell, the B cell is part of the cellular arm. But I could also argue that the B cell is part of the humoral immune system, if I were looking strictly at the effector functions.
And then we can talk about T-independent antigens, and how B cells act autonomously in these situations... one of these days I'll write the World's Best Immunology Textbook, and explain all of this.
Immunology is so much fun!!!!
Question: I read that most medical schools only provide a week's worth of training on chronic pain. Is this true? How much exposure to autoimmune disease research do med students receive?
Dr. EricThis is true, and it's also true that most medical students only get about one week of exposure to autoimmune diseases. One of my students told me that the national board exam had only one question regarding autoimmune diseases, so it is not surprising that most GP's have trouble identifying and diagnosing ANY autoimmune disease, much less PAN.
We are fighting ignorance of these diseases, and sometimes it seems like an uphill battle
Dr. Eric, do you have any comments from what you know about this Rare Disease Network. How do you think it will impact your job as a scientist and researcher?
This NIH initiative will channel research money better, so that there are fewer small projects that are redundant, and will bring researchers with similar interests together. It will combine research projects that are looking at similar problems (PAN, microscopic polyangiitis, WG) so that an advance in one area can be applied to all of the pertinent diseases.
In general I'm opposed to big government running the show, but this is one area where I think NIH is doing it right. By putting together these consortia, and allowing experts in each area administer the consortia, the money will be spent wisely, and should lead to advances in our knowledge of these diseases.
I am suffering from Shingles. Please tell about this condition.
Alvin, I've never had shingles, but I've seen dozens of cases, and I understand the pain that you are suffering right now. Shingles commonly occurs in patients who are on immunosuppressive drugs. Remember when you were a kid and had chickenpox? That virus set up shop in your nerves, and has been riding along in all of your travels ever since then. In most people, it's happy just to stay dormant and go along for the ride, but in some people it reactivates.
This can be caused by immunosuppressives, stress, or even aging. Of course, in a young guy like you who has no stress in his life <GRIN>, it must be the immunosuppressive drugs.Treatment includes anti-virals, pain meds, and topical treatment, all of which your doctor has prescribed. I would suggest that you get some Aveeno bath and add it to your bath water. This is an over-the-counter product made from oats. It is very soothing for the pain of shingles. You may look like a cranberry in a bowl of grits, but it does help the pain.
The virus can be found in the blisters on the skin, and could be transmitted to someone who has never had chickenpox, so you want to stay away from very young children. Exposure to the virus will not trigger a shingles reaction in someone with a normal immune system, who has had chickenpox in the past. Younger people who have had the chickenpox vaccine are also safe from the virus.
The rash can last for a few days to a few weeks. Unfortunately, the pain (zoster neuralgia) can last for months after the rash disappears.
You will need to work with your doctor to help suppress that pain.You are in our prayers. My wife added your name to the prayer chain, so you have a couple of hundred people in the south suburbs who are lifting your name today. This is a scary problem, but with your strength, the strength of the Lord, and all you have been through already, I am confident that you will handle it.
Praying for you,
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