Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by progressive
damage of synovial-lined joints and variable extra-articular manifestations. Tendon
and bursal involvement are frequent and often clinically dominant in early disease.
RA can affect any joint, but it is usually found in metacarpophalangeal, proximal
interphalangeal and metatarsophalangeal joints, as well as in the wrists and knee.
Articular and periarticular manifestations include joint swelling and tenderness to
palpation, with morning stiffness and severe motion impairment in the involved joints.
The clinical presentation of RA varies, but an insidious onset of pain with symmetric
swelling of small joints is the most frequent finding. RA onset is acute or subacute
in about 25% of patients, but its patterns of presentation also include palindromic
onset, monoarticular presentation (both slow and acute forms), extra-articular synovitis
(tenosynovitis, bursitis), polymyalgic-like onset, and general symptoms (malaise,
fatigue, weight loss, fever). The palindromic onset is characterized by recurrent
episodes of oligoarthritis with no residual radiologic damage, while the polymyalgic-like
onset may be clinically indistinguishable from polymyalgia rheumatica in elderly subjects.
RA is characteristically a symmetric erosive disease. Although any joint, including
the cricoarytenoid joint, can be affected, the distal interphalangeal, the sacroiliac,
and the lumbar spine joints are rarely involved. The clinical features of synovitis
are particularly apparent in the morning. Morning stiffness in and around the joints,
lasting at least 1 h before maximal improvement is a typical sign of RA. It is a subjective
sign and the patient needs to be carefully informed as to the difference between pain
and stiffness. Morning stiffness duration is related to disease activity. Hand involvement
is the typical early manifestation of rheumatoid arthritis. Synovitis involving the
metacarpophalangeal, proximal interphalangeal and wrist joints causes a characteristic
tender swelling on palpation with early severe motion impairment and no radiologic
evidence of bone damage. Fatigue, feveret, weight loss, and malaise are frequent clinical
signs which can be associated with variable manifestations of extra-articular involvement
such as rheumatoid nodules, vasculitis, hematologic abnormalities, Felty's syndrome,
and visceral involvement. Although there is no laboratory test to exclude or prove
the diagnosis of rheumatoid arthritis, several laboratory abnormalities can be detected.
Abnormal values of the tests for evaluation of systemic inflammation are the most
typical humoral features of RA. These include: erythrocyte sedimentation rate, acute
phase proteins and plasma viscosity. Erythrocyte sedimentation rate and C-reactive
protein provide the best information about the acute phase response. The C-reactive
protein is strictly correlated with clinical assessment and radiographic changes.
Plain film radiography is the standard investigation to assess the extent of anatomic
changes in rheumatoid arthritis patients. The radiographic features of the hand joints
in early disease are characterized by soft tissue swelling and mild juxtaarticular
osteoporosis. In the the past 10 years, ultrasonography has gained acceptance for
studying joint, tendon and bursal involvement in RA. It may improve the early clinical
assessment and the follow-up of these patients, showing such details as synovial thickening
even within finger joints. Other imaging techniques, such as magnetic resonance, computed
tomography and scintigraphy may provide useful information about both the features
and the extent for anatomic damage in selected rheumatoid arthritis patients. The
natural history of the disease is poorly defined; its clinical course is fluctuating
and the prognosis unpredictable. RA is an epidemiologically relevant cause of disability.
An adequate early treatment of RA may alter the diseas