Worried about Dad

So my Dad has recently been having some health problems. He has had arthritis for years but over the last few months he started having night sweats, swelling of his lower feet and legs and generally being in so much pain with his joints he can hardly move.

He went to the Dr who suspected that the arthritis had progressed to rheumatoid arthritis. They put him on steroids and took blood and he was then referred to rheumatology as his blood showed high levels of inflammation.

He attended a hospital appt last week, (his symptoms are much better since he's been on steriods) and they took x rays and more bloods and said he would receive notification of a follow up appt.

He has now in the post received two letters from the hospital, one with a follow up appt for rheumatology and the other for CT Scans with contrast for abdomen and chest. The CT scans are week after next.

I just wondered does anyone know if this is standard for Rheumatoid arthritis. Obviously with my HA I'm starting to worry as I can't see why they need scans of the abdomen or chest unless they are looking for something else.

My Dad is a bit perplexed by it as he said they didn't mention to him he'd need CT scans. I obviously haven't said anything as I don't want to worry him, but I am worrying and just wondered if anyone had any experience of this.

Thanks