Should I have temporal biopsy for GCA even after 8 weeks prednisone?

I was diagnosed with GCA and PMR about 8 months ago. My GCA was confirmed with a biopsy the second day of treatment with high dose prednisone. My sed rate was 54 and my CRP was 9. I just googled "how long is a temporal artery biopsy valid after starting prednisone for GCA", and the results varied from 1 to 4 weeks, but I did find one small study where a positive biopsy occurred after 45 days of prednisone treatment. My understanding is that besides the recovery of giants cells from prednisone treatment, the biopsy can have a false negative by being performed in a section of the artery where there aren't any giant cells (skip lesions). I would advise you to not have the biopsy, but your headaches are concerning. I never had headaches with my GCA, but I had almost all of the other standard symptoms, including episodes of temporary vision loss in one eye. I got treatment in time to save my vision.

Thank you for your reply. I have read the same kinds of things about skip lesions and prednisone treatment potentially producing a false negative reading. I was diagnosed after complaining of pain and stiffness for a little over 2 weeks which my PCP ignored as possible statin side effect ( new medication for me)and told me to try to continue statin. I finally threw in the towel because of excruciating pain and told him I would not continue statin and asked if I had PMR...a friend suggested that's what I had. PCP ran blood work and although my inflammation markers were low, he diagnosed PMR. So, I started prednisone at 20 MG for 1 week. Then he lowered it to 15MG for 20 days....then he wanted me to go to 10 MG, but I balked because of all I had read about slower taper and I went to 12.5 MG for another 19 days. Then I saw rheumatologist...she wants the GCA test because of headaches, but at this point I don't think ultrasound or biopsy are going to be reliable...so what do I do? Get another opinion? My inclination is to try ultrasound because it cannot hurt. I wish I could remember when the headaches started...if it was only after the prednisone, is it possible that these are prednisone headaches?

I haven't headaches either before or after my diagnosis, but a lot of websites do list headaches as a possible side effect of prednisone. Maybe someone who had headaches from their GCA can describe what they felt like.

I was diagnosed with PMR and possible GCA in July 2024. My sed rate and CRP were both high and I had headaches in the area where GCA headaches can occur. I was immediately put on 60 mg. of Prednisone for the possible GCA. I had an order to get a bi-lateral temporal biopsy and got it on day 8 after my diagnosis. My rheumatologist and primary told me that after 14 days, the test may not be reliable due to my taking the high dose of pred. The biopsy came back negative, but with the caveat that it didn't necessarily indicate that I didn't have GCA. They may not have sampled an affected artery.

The biopsy on the temperal artery is a piece of cake, Does not hurt but keep the bandage on until it falls off , which is two to three days as the bandage will be on your hair as well. Mine was an emergency bx as we were leaving the country a couple days after for 6 weeks. I had to go to the local hosital for lab work. Was put on prednisone and an antibiotic because of the tropics. I would advise the biopsy as I read PMR can be followed by GCA. DO NOT PROLONG TREATMENT.

Thank you for your response. I am wondering if you actually had GCA, PMR or both and how your treatment went? I am, as I previously stated, trying to understand having a biopsy which I think will be possibly negative because of 8 weeks of prednisone already. Then what? Do I get full blown treatment for GCA because I have temporal headaches and ocular migraines or not?
If yes, then why have the biopsy in the first place?

How are you doing now? Did yo receive any of the new drugs {biologics) along with the prednisone? I hope things are going well for you.......

I received my first Actemra infusion in January 2025. I started feeling better about 3 weeks after it. I get them every 4 weeks. I can honestly say that I feel GREAT now. Still wake up with minor aches, but they're manageable. I am now on 9 mg. of pred. will step down to 8 in 2 weeks. I feel as good as I've felt, since before PMR. I was always VERY active. I have 3 golf t-times this week. I've riden my e-bike anywhere from 8-24 miles. I feel like I'm 'back'.

In October 2023 I was diagnosed with GCA after 42 days of headaches. I was put on 60 mg of prednisone for a month. The headaches stopped. I also have PMR. We continued with a very slow taper of prednisone until I was able to stop completely in June 2024. My rheumatologist diagnosed GCA initially without a biopsy or ultrasound. My personal thoughts are if you’re still having headaches, you might need to be on a stronger dose of prednisone for awhile.

Thank you for your comments....I appreciate hearing from everyone. I think GCA can start before PMR as well as sometime after PMR. Tomorrow I have temporal and axillary artery ultrasound; since my dose of prednisone is low, perhaps the "Halo" might still show up in the artery if GCA is there and if it started after PMR. We'll see. Has anyone had a PHONE second opinion and if so, were you satisfied ?