CRP and ESR Blood Tests

[visionatsea]

Diagnosed with PMR in Dec 2018. CRP and ESR tests have been producing similar results until last test (i.e., ESR = 3; CRP=29; where 0-30 and 0-10 respectively are normal). Had a spell of inflammatory arthritis which was treated and have tapered to 5mg and feeling fine. What are the differences in ESR and CRP tests? Are there situations where one is preferred to the other? How to interpret recent results?

[Hidden]

Hi, I flam arthritis probably accounts for upswing as any infection/inflammatory conditions can raise them as can stress. I think this explains crp and esr quite well and certainly better than I could. Come back at us with questions... But if you feel OK then just go with your plan.... Until you don't!

practicalpainmanagement.com...

[visionatsea in reply to Hidden]

Thank you. I went to the pain management sight and searched under the two tests. Came up with, for a non medical person, somewhat understandable and informative. Will need to read it a couple times to get the full meaning. Again, very much appreciate the reply.

[Hidden in reply to visionatsea]

I think they tend to do one (can never remember which) because the test conditions are more forgiving. I always say if you don't need to read something several times... Its not worth knowing. 🤔😂🤣😂

[PMRpro Ambassador]

CRP is a protein produced by the liver in response to the presence of inflammation in the body. ESR is the rate at which the red blood cells settle to the bottom of a vertical tube and that is influenced by the presence of proteins on the surface of the red cells. So the ESR often rises when the CRP rises - but not always, and in some people neither of them move much despite symptoms.

CRP is perceived to be more reliable as it is a direct measurement and is influenced by spurious factors less than ESR. However, although there is a degree of movement to remove ESR from the options because of the unreliability, there is also some support for retaining ESR in the context of PMR because it does seem to work well there.

The vast majority of patients had never had them measured before developing PMR so have no idea what their personal normal ESR is - CRP is rather more stable between different people, It is worth getting your doctor to check them regularly for some time to find how they work for you.

But basically - a single raised value without a return/increase in symptoms shouldn't result in a kneejerk increase in dose. The test should be repeated to see if there is a trend.

[visionatsea in reply to PMRpro]

Thank you for your response. Picked up some of that from the pain mgt. site previously suggested. I've tried to put some of my previous test results in a table that might provide you with more insight into my case. Not had good result submitting this format to web sites in the past, but here goes. This shows a yo-yo record of tapering until about Dec 12,2019 when a successful tapering effort began. It was interrupted by inflammatory arthritis in Feb. 2020, which was treated (successfully?) with prednisone. I am back to 5mg and am planning to continue to zero, if possible. Have no PMR symptoms that I can discern, nonetheless, do have osteo and inflammatory arthritis in knee and tendonitis in shoulder that are treated, as needed, with cortisone shots. My doc wants me to hold at 5 mg until I see her in May 2020, but I am anxious to get to 0mg. Any add'l thoughts or insights would be appreciated.

9/23/2019 10/23/2019 11/18/2019 12/10/2019 1/10/2020 3/2/2020

ESR 7 20 8 19 5 3

CRP 12 23 2 12 6 29

[PMRpro Ambassador in reply to visionatsea]

I'd suspect that might well be the leftovers of the arthritis.

I also suspect that the aim of the doctor is to let your adrenal function catch up. One top PMR rheumy in the UK likes to keep patients at 5mg for up to 9 months - and finds the onward journey is often far far easier.