Bone marrow disorder?

@pdxmac, I think you might be referring to the reference posted by Mike @dadcue about IL inhibitors and bone marrow here - https://connect.mayoclinic.org/comment/1442399/.

You don't mention which one you're on so I went to the Claude app for some general information for kevzara and tocilizumab. While they can negatively impact neutrophils, they are generally beneficial when it comes to iron.
Here's what Claude had...
Neutrophils — Negative
Both tocilizumab and Kevzara cause drops in circulating neutrophil counts (ANC), which is why regular blood monitoring is required. The good news is it's not true bone marrow damage — it's redistribution of neutrophils into tissues — and it doesn't reliably translate into higher infection rates. But it can still trigger dose holds and occasionally discontinuation, more so with Kevzara than tocilizumab.
Iron — Beneficial
By blocking IL-6, both drugs suppress hepcidin, which is the hormone that locks iron away in macrophages. Lower hepcidin means more iron is available for red blood cell production. This can meaningfully improve anemia of inflammation, sometimes within just 2 weeks of starting treatment. Again, tocilizumab has the stronger published evidence here, but the mechanism is the same for both.
The key distinction worth remembering:
The neutropenia is a lab finding that requires monitoring but rarely causes clinical problems. The iron benefit is a real clinical improvement that can reduce fatigue and improve quality of life in patients who were anemic from chronic inflammation. So in many patients, the benefits to iron and anemia will outweigh the concern about neutrophil numbers — especially if tocilizumab is chosen over Kevzara given its slightly milder neutrophil impact.

@pdxmac

Are you anemic? Is that why you are asking? If your red blood cells (RBCs) are low that is something different than your white blood cells (WBCs ) being low.

There is something called "anemia of inflammation." but it is also called Anemia of Chronic Disease.

I like how Cleveland Clinic explains things:
https://my.clevelandclinic.org/health/diseases/14477-anemia-of-chronic-disease
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There was a nice discussion about anemia and PMR not too long ago.
https://connect.mayoclinic.org/discussion/pmr-diagnosis-and-anemia/

If your blood ferritin is good or high, I would wonder why you are on an iron supplement. My doctor told me not to take any iron until they found the cause of my anemia. Too much iron in your blood can be a disaster. Please be careful.
Have the tested your vit B?
I have anemia of an undetermined cause, they can not treat it with any drug. If I became too anemic they will need to do a transfusion. Steroids help keep my hemoglobin up. PMR is like dancing with the devil, my opinion.

Thank you everyone for the input! I have been on Tyenne for my infusions. They have done a lot of blood tests and my vitamin B 9 + 12 are okay, as is my WBC, RBC, RDW/SD, reticulites and hemoglobin. They started doing extra testing when they noticed abnormal red blood cell shapes. The amount of ferritin is fine, but the iron saturation is at only 13%. That's why they started me on the iron supplement. I'm only two pills into it, and more blood work is ordered for next week. The impression I'm getting is that they can't figure it out.

@pdxmac have you been on methotrexate as well recently. It played havoc with my red and white blood cells over an 18 month period. Everything returned to normal after around 3 weeks but I was very ill at the time and they started to suspect bone marrow cancer initially ignoring the obvious culprit.

I was, from Feb 25 through November. The blood numbers were a little wacky so that's why we stopped. I think since they're more normal now, whatever damage was done is no longer an issue.