Review Question - QID 106428

The morning stiffness lasting more than one hour and radiographic findings demonstrating joint space narrowing and erosion of the proximal interphalangeal joints (PIPs) makes rheumatoid arthritis (RA), answer 3, the most likely.

RA is a symmetric, inflammatory polyarthritis. RA should be considered in any patient presenting with joint pain and morning stiffness at least for one hour before maximal improvement for an extended period of time (usually >6 weeks). The diagnosis of RA is confirmed with imaging, positive rheumatoid factor (RF) and/or anti-citrullinated peptide antibody (anti-CCP), and elevated C-reative protein or erythrocyte sedimentation rate.

As Wasserman notes, caution should be used with interpreting RF results. RF is not specific for RA and can be positive in individuals with other diseases (e.g. hepatitis C) or in healthy older individuals.

Aletaha et al. outline specific criteria for the diagnosis of RA, which was most recently established by the American College of Rheumatology and European League Against Rheumatism in 2010. These guidelines were established in an effort to diagnose RA earlier in patients who may not meet the previously used guidelines (the 1987 American College of Rheumatology classification criteria).

Figure A shows a radiograph of a person with RA. Illustration A is a table outlining key differences in RA vs. OA. Illustration B is a table outlining characteristics of different arthritides. Illustration C shows the 2010 American College of Rheumatology/European League Against Rheumatism Classification Criteria for RA. Illustration D lists extraarticular manifestations of RA. Illustration E shows the hands of a person with RA. Note the swelling in the MCP joints, but not the DIP joints. Also, note the ulnar deviation, which is another common finding in RA.

Incorrect Answers:
Answer 1: Gouty arthritis is usually monoarticular and tophi may appear on imaging.
Answer 2: Morning stiffness in OA lasts less than an hour.
Answer 4: Psoriatic arthritis shows a pencil-in-a-cup deformity on imaging.
Answer 5: SLE would most likely present with many other constitutional symptoms (e.g. malar rash, photosensitivity, etc.) and is less common than RA.