To be a good rheumatologist, you will need excellent general internal medicine knowledge since our disease affect all the organ systems. Some patient would like to treat us as their PCP. However, there is such a shortage of rheumatologist currently that it's difficult to have enough appointments/time slot to accommodate non-rheumatological issues. Most of our disease are complex and just explaining the rheum diseases, it's pathophys, mediations, side effects, yada yada takes up most of the visit. I can't imagine trying to squeezing DM management, blood pressure management, screening test, etc in that visit.
Personal belief here: I don't want to miss anything rheumatological by focusing too much. Their other doctors are not going to focus on the labs indicating lupus progression/flare or that the development of lung dz in an RA pt or that bump in Cr ( with an unusually elevated BP) for a systemic scleroderma pt. They expect me to be on top of those ( as they should, since I am the rheumatologist). If I start doing a PCP's job, it's too easy to miss what I am suppose to be doing. It is also, IMHO, a sure way of burning out. I will stay in my lane and provide the best rheumatological care for my patient. I had a pt "fire" me for not taking care of their chronic issues in addition to their rheum issues. Honestly, I was ok with that.
If you plan on going to a rural area, I am sure they would love to have a rheumatologist ( been offer 300-400K in rural areas, but no money is worth it for me) and they would love a rheumatologist who will practice as a PCP. I suspect a rural rheumatologist will have more straightforward rheum patients as oppose the complex patient at an academic setting, maybe practicing both ( PCP + rheum) is possible? I am not trying to insult rural rheumatologist with the above statement but I honestly believe that a complex rheum patient need a multidisciplinary team in an academic setting with all it's resources ( Systemic scleroderma: rheum, pulm for ILD/PAH, GI for esophageal dysmotility &/ SBO, etc).
Hope this was somewhat helpful...
ETD: correct stuff... tapping on phone is hard
EETD: I had a rural PCP message me on Social media few months ago asking about whether their pt had lupus ( no rheum around that part apparently), so they would LOVE a rural rheumatologist.