What is your approach to a patient with RF+/CCP+ rheumatoid arthritis that was previously on TNFi now with high-titer ANA and dsDNA (crithida 1:2560), +chromatin, +histone?

This scenario reads like TNF inhibitor drug-induced serological lupus. The first clinical issue is: are there accompanying symptoms or signs of systemic lupus erythematosus (SLE) beyond the underlying inflammatory arthritis, which would be better attributed to the seropositive rheumatoid arthritis (RA) for which the TNF antagonist had been prescribed in the first place? For example, is there fever, cutaneous lupus, serositis, immune cytopenia, or most worrisomely any evidence for nephritis, such...

A key part of this question is "previously on TNFi." Anti-TNF-induced lupus (ATIL) usually resolves within 2-8 weeks after stopping the TNFi. This includes anti-dsDNA, which is usually at low to moderate titers when seen in ATIL, rather than the high-titer Crithidia dsDNA as is seen here.

High positive Crithidia anti-dsDNA, inflammatory arthritis, and chromatin and histone antibodies are highly suggestive of possible idiopathic systemic lupus erythematosus (SLE), more so than ATIL. The patient co...