A 31-year-old female medical secretary presents to her GP with a two-month history of painful and stiff hands. The pain gets better throughout the day, but she has to get up 3 hours before work to have time for the stiffness to subside. On examination, there is swelling over all metacarpophalangeal joints and proximal interphalangeal joints on both hands.

What is the most likely diagnosis?

Options:
explanation: Osteoarthritis is a non-inflammatory "wear and tear" arthritis. It presents with degenerative joint pain. This means there will not be any morning stiffness (or <30 minutes), and the pain gets worse on exercise. In addition, osteoarthritis typically affects those over 45 years old and has a longer, more gradual onset (typically over years). Although osteoarthritis can affect the hands, it is unlikely to affect so many joints in the hand symmetrically
name: Osteoarthritis
label: b
answer: no
explanation: Enteric arthropathy is a spondyloarthropathy that is often associated with inflammatory bowel disease. The joints affected include the spine and large peripheral joints. The absence of inflammatory bowel disease and the distribution of joint disease makes enteric arthropathy a less likely diagnosis
name: Enteric arthropathy
label: d
answer: no
explanation: Psoriatic arthritis is also an inflammatory arthritis. Symmetrical polyarthritis is a subtype of psoriatic arthritis that can present in the same distribution shown in the question. However, it tends to be associated with skin psoriasis, so many patients will also present with psoriatic plaques or psoriatic nail changes (although some patients will still not present with skin psoriasis). In addition, psoriatic arthritis also tends to affect the distal interphalangeal joints (DIPJ), unlike rheumatoid arthritis. The absence of DIPJ involvement and skin psoriasis makes a diagnosis of rheumatoid arthritis more likely
name: Psoriatic arthritis
label: c
answer: no
explanation: Rheumatoid arthritis is an inflammatory arthritis that can present at any age but typically presents in middle-aged females and smokers. It typically comes on over a few months, with pain and stiffness improved with exercise and worsened by rest, along with prolonged morning stiffness. The typical distribution in early rheumatoid arthritis is the metacarpophalangeal joints and proximal interphalangeal joints in the hands and the small joints of the feet and wrists. The distal interphalangeal joints are characteristically not affected in rheumatoid arthritis. This patient should have some blood tests, hand x-rays and a referral to rheumatology for consideration of a disease-modifying anti-rheumatic drug (DMARD)
name: Rheumatoid arthritis
label: a
answer: yes
explanation: Systemic lupus erythematosus (SLE) is a connective tissue disease that presents with inflammatory arthritis. However, there are often other extra-articular features in SLE, including fatigue, fever, weight loss, alopecia, malar rash, pericarditis, pleural effusion, blood abnormalities, neurological involvement, and there is an association with antiphospholipid syndrome. None of these features are present in this case, making a diagnosis of SLE less likely
name: Systemic lupus erythematosus
label: e
answer: no

Correct answer: a