Rheumatoid Arthritis in MRCP

RHEUMATOID ARTHRITIS

RA is a type of autoimmune disease mainly involving joints. It leads to chronic inflammation of joints. However, candidates must remember that it is a multi-system disease that might involve other organs as well such as skin, eye , lung and cadiovascular. More female are affected with a ratio of 3:1.

Clinical Presentations

Majority of patients present with small joints pain. However, patients may have systemic symptoms such as fever, weight loss and fatigue.
Some patients may have eye symptoms such as red , painful eye ( due to scleritis and episcleritis)
There is possibility of lung fibrosis
Patients may have neurological deficits due to alanto-axial subluxation or mononeuritis multiplex.

Physical signs

Classical hand deformities are Z deformity, Swan neck , Boutonniere deformity, to learn more click www.passpaces.com/issue1.html
Lung fibrosis



Diagnosis

Diagnosis can be made based on American Rheumatism Association Criteria:
1) Morning stiffness >1 hour for 6 weeks or more
2) Swelling of at least 3 joints for 6 weeks or more
3) Swelling of wrist, MCP,PIP joints for 6 weeks or more
4) Symmetrical joints pain for 6 weeks or more
5) Subcutaneous nodules
6) +ve RF
7) Classical X ray appearance ( periarticular osteopenia)

Four or more out of seven criteria above, the diagnosis can be made

Investigations

Rheumatoid factor (RF)- however this is not specific, it can be positive in normal population ( false postive)
FBC- anaemia- Remember 4 causes of anaemia in RA- Chronic illness, Felty syndrome, Drug-induced (anaemia due to UGIB, secondary to gold, methotraxate)
Xray- lung ( fibrosis), hand, cervical ( subluxation)

Treatment

Disease modifying drugs such as sulphasalazine, methotraxate, gold
Latest drugs such as etanercept and infliximab- popular questions in MRCP, click here to learn more!

Tips for MRCP

1) Remember the side effects of drugs used to treat RA including etanercept and infliximab!