Polymyositis & Dermatomyositis Support Group
Polymyositis (PM) is a type of chronic inflammation of the muscles (inflammatory myopathy) related to dermatomyositis and inclusion body myositis. The inflammation is predominantly of the endomysium in polymyositis, whereas dermatomyositis is characterized by primarily perimysial inflammation.
When I was first put in the hospital with my problems I was immediately put on IV high dose prednisone. I don't remember the dosage, but it was well over 1000mg. It took more than a couple weeks for me to stabilize. Stability in this case was my CPK/CK levels lowering to safer levels. The doctors waited for that stabilization before they did a muscle biopsy from my shoulder. And based on that biopsy they confirmed the initial diagnosis of DM.
I have read that prednisone can hide some indicators, but at that time my docs didn't seem concerned and used the biopsy results. At this time, we cannot find the DM antibodies in my blood and, I guess, assume it is the prednisone that is hiding it.
So, it seems to me it depends on the docs disposition whether prednisone effects are significant, which isn't as scientific as one would expect IMHO. So part of getting a reliable diagnosis is finding the right doc, which doesn't seem right to me either. If John Hopkins is an option do it. The more expert opinion you can get on your condition the better. This is a RARE and alot of people in the medical arena have never heard of it or never seen it.
My rheumatologist is sending me to a dermatologist for a skin biopsy ...
If you decide to go to JH, know what you want out of it. Also know that they will want many tests to have been done. For me, I needed to have a muscle biopsy, MRI, CT Scan, and a Myositis Panel (blood work). They wanted the past clinical notes and any test results I've had. I sent them over 80 pages of information before they would consider giving me an appointment. I don't mean to discourage you and perhaps your experience will be easier but I wanted to share. It has been a great experience for me.
I was also on Prednisone while going through diagnosis. I couldn't wait and I couldn't go off. I was on 60 mg at the time. I was on it for almost 5 years before I was able to get off but not everyone can get off. It took me a few years to get down from 10 mg to off. So be patient and if it helps, don't be too anxious to jump off. Our bodies naturally create about 7-10 mg so taking 10 mg isn't too bad since it is the rate your body makes anyway (Your body stops making when on Prednisone long term). I was on an every other day dose that helped me get off. You might want to talk to your doctor about that. Seems everyone has a different approach to get lower. I was on 2.5 mg every other day for about 6 months. That was a good dose for me but I wanted to try to get off and we did.
Hang in there. Diagnosis is tough. If you have easy access to Mayo Clinic or Dr. Ascherman, maybe check those out first. I've met Dr. Ascherman at the TMA conferences. Very knowledgeable and friendly.