Rheumatoid arthritis: Cause, Diagnosis and Treatment
Chronic progressive inflammatory disorder characterized by joint pain, swelling, redness and disability.
Etiology of Rheumatoid arthritis
(i.) human leukocyte antigen (HLA)-DRB1 locus (in patients positive for rheumatoid factor) activates the autoantibody production (rheumatoid factor and anti-citrullinated protein antibody [ACPA]) via T cell activation pathway
(ii.) Infectious agents (eg Epstein-Barr virus, Cytomegalovirus, Proteus species, and Escherichia coli) and their products (e.g., heat-shock proteins)
(iii.) Nuclear factor $\kappa$B (NF-$\kappa$B)-dependent signalling pathway.
Morning stiffness, fatigue, weakness, low-grade fever, loss of appetite, and joint pain, myalgias may precede development of synovitis.
Polyarticular: Intercarpal and carpal-metacarpal-phalanges joints are firstly affected followed by the joints of wrists, ankles, elbw, tarsal-metatarsal-phalanges, shoulder girdle and pelvic girdle.
Elevated erythrocyte sedimentation rate and C-reactive protein, positive rheumatoid factor (60% to 70% of patients); positive anticyclic citrullinated peptide antibody (50% to 85% of patients).
Soft tissue swelling and osteoporosis near the joint (periarticular osteoporosis) in the early stage of the disease, joint erosions later in the disease, pennus formation, decalcification of localized area.