Reclassifying the pathogenesis of rheumatoid arthritis: from the susceptibility to the degenerative stages

Rheumatoid arthritis is a heterogeneous disease in which different pathogenic mechanisms have been suggested. Recent advances in immunology and immunogenetics have contributed to a better understanding of this complex illness. Several stages have been previously described, based on clinical and radiological findings, and proposing different therapeutic options. We have analysed previous classification schema, making some changes and incorporating new knowledge. Our classification system includes a susceptibility stage and a degenerative stage. Therapeutic options are described for each stage. We hope that this will provide useful guidelines in the future for clinicians and researchers.