How would you approach a patient with seronegative RA and ILD?   

Initially presented as PMR clinically, no signs of myositis, however despite RF/CCP negative it appears to be transitioning more to a classic RA picture in terms of joints involved. There is overlap between RA and PMR so now hard to distinguish seronegative RA vs PMR with peripheral involvement now. Trying to decide trial of MTX/LEF vs IL-6.