- RA is usually a disease of insidious onset, although it can be
abrupt. The diagnosis is typically made when four out of seven qualifying criteria
established by the American Rheumatism Association are met. These qualifying criteria are
- Morning stiffness lasting greater than one hour before
- Arthritis involving three or more joints
- Arthritis of the hand, particularly involvement of the
proximal interphalangeal joints (PIP), the metacarpolphalyngeal joints (MCP) or wrist
- Symmetric involvement of the same joint areas bilaterally
(i.e., both wrists, symmetric PIPs and MP joints)
- Positive serum rheumatoid factor
- Radiographic evidence of rheumatoid arthritis
- Other contributing history includes the following:
- Fever of undetermined etiology
- Joint involvement is typically polyarticular and symmetrical,
usually sparing the distal interphalangeal (DIP)joints. Joint involvement and inflammation
is evidenced by the following:
- Destruction (a late finding)
- Subcutaneous rheumatoid nodules, "swan neck"
deformities, "Boutonniere" deformities, ulnar deviation of fingers at MCP joints
- RA is a diffuse systemic disease involving many areas of the
body. The presenting complaint may be remote from a joint or may involve inflammatory
symptoms at a joint.
- The cause of rheumatoid arthritis has not been elucidated.
- Associated factors may include: