Rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder that causes the immune system to attack the joints. It is a disabling and painful inflammatory condition, which can lead to substantive loss of mobility due to pain and joint destruction.

Table of contents

1 Signs and symptoms
2 Diagnosis
3 Classification
4 Pathophysiology
5 Treatment
6 See also
7 External links

Signs and symptoms

The symptoms that distinguish rheumatoid arthritis are inflammation and soft-tissue swelling of many joints at the same time (polyarthritis). The hands are generally affected in a symmetric fashion. The pain generally improves with use of the affected joints, and there is usually stiffness of all joints in the morning that lasts over 1 hour.

If the arthritis has been longstanding, the inflammatory activity has led to erosion and destruction of the joint surface, which impairs their range of movement and leads to deformity. The fingers are typically deviated towards the little finger (ulnar deviation) and can assume unnatural shapes.

Subcutaneous nodules in specific places, e.g. the elbows, are often present.

Diagnosis

When RA is being clinically suspected, immunological studies are required, such as rheumatoid factor (RF, a specific antibody). A negative RF does not rule out RA; rather, the arthritis is called seronegative. Usually, several other blood tests are done to allow for other causes of arthritis, such as lupus erythematosus. The erythrocyte sedimentation rate (ESR), C-reactive protein, full blood count, renal function, liver enzymes and immunological tests (e.g. antinuclear antibody/ANA) are all performed at this stage. Ferritin can reveal hemochromatosis, which can mimic RA.

Classification

The American College of Rheumatology has defined (1987) the following criteria for Rheumatoid Arthritis [1]:

Morning stiffness of >1 hour.
Arthritis and soft-tissue swelling of >3 of 14 joints/joint groups
Arthritis of hand joints
Symmetric arthritis
Subcutaneous nodules in specific places
Rheumatoid factor at a level above the 95th percentile
Radiological changes suggestive of joint erosion

Four criteria have to be met, although many patients are treated despite not meeting the criteria.

Pathophysiology

To be written

Treatment

Treatment is with NSAIDs, although most patients will proceed to treatment with steroids, DMARDs (disease-modifying antirheumatic drugs), and monoclonal antibodies (anti-TNF-alpha, e.g. infliximab or etanercept). Other therapies are weight loss, physiotherapy and special tools to improve hard movements (e.g. special tin-openers).

Severely affected joints may require joint replacement surgery, such as knee replacement.