How would you approach a patient with anti-scl70 ab positive sine scleroderma complicated by ILD who also has seropositive RA with active arthritis?

This scenario can be looked at in different ways. For example, does this patient have scleroderma that explains the ILD and seropositive RA to explain the arthritis? Or, does this patient have seropositive RA which explains both the arthritis and the ILD? I favor the latter explanation.

In this scen...

When using MTX in this situation, we monitor DLCO closely, age every 6-12 months. If the DLCO drops, this could indicate worsening ILD or MTX effect and in this case we would stop MTX as a precaution. Otherwise, if MTX is appropriate for managing the arthritis, we would start with it.