Difficult-to-treat systemic lupus erythematosus: from refractory disease to a multidimensional clinical trajectory.
Difficult-to-treat (D2T) systemic lupus erythematosus (SLE) is increasingly recognised in clinical practice but is still conceptually underdeveloped. In contrast to rheumatoid arthritis and psoriatic arthritis, for which formal D2T frameworks have been proposed, SLE still lacks a multidimensional model capable of captu...