Polyarthritis

Question 1

Osteoarthritis- cause

Answer 1

Mechanical wear and tear of the larger weight baring joints e.g. hip, knee (localised disease). Worsened by obesity.
And also the carpometacarpals (generalised disease)

Question 2

Osteoarthritis- symptoms

Answer 2

Pain, reduced function, crepitus on moving larger joints. Painful with increased activity. Perceived lack of power. Unilateral. Background ache at rest.
CMP joints- Heberden’s - DIP- and Bouchard’s -PIP- nodes.

Question 3

Osteoarthritis- XR findings

Answer 3

L- loss of joint space
O- osteophytes, bone spurs
S- subchondral sclerosis
S- subchondral cysts

Question 4

Osteoarthritis- management

Answer 4

Weight loss and muscle strengthening exercises
1st line: paracetamol and topical NSAIDs
2nd line: oral NSAIDs, not if taking aspirin. Short term opioids. Capsaicin cream.
Intraarticular steroid injections.
Last resort if seriously life limiting is a joint replacement.

Question 5

Rheumatoid arthritis- cause

Answer 5

Autoimmune condition that causes systemic inflammation.

Immune system reacts to citrullinated proteins and develops anti-citrullinated peptide antibodies, anti-CCP

Question 6

Rheumatoid arthritis- symptoms and findings

Answer 6

Symmetrical polyarthritis, typically in the MCP and PIP joints.
Painful swollen hands and feet.
Morning stiffness that improves with use.
Systemic upset- pul fibrosis, effusions, nodules. Episcleritis, scleritis, corneal ulceration, keratoconjunctivitis. Osteoporosis, ischemic heart disease, depression.

+ve squeeze test.
Boutonniere deformity, swan neck deformity, Z deformity at wrists, ulnar deviation.

Question 7

Rheumatoid arthritis- XR findings

Answer 7

Synovial membrane hyperplasia, cartilage damage, bony erosions, destruction of surrounding structures
USS can show synovitis better than XR.

Question 8

Rheumatoid arthritis- diagnosis

Answer 8

> 1 joint affected with no other explanation.
Score of 6/10 is needed for diagnosis, based off serology results, how many joints are affected, duration of symptoms etc

Rheumatoid factor, RF- circulating IgM antibody that reacts with Fc region of patients own IgG. First line test for suspected RA. Can be raised in other diseases.

Anti-CCP- detectable 10 years before symptom onset, allows for aggressive anti TNF preventative therapy. Better specificity than RF.

Question 9

Rheumatoid arthritis- management

Answer 9

DMARDs- disease modifying anti rheumatoid drugs.
1st line. Take 6-12 weeks to work so consider bridging prednisolone.
Examples: methotrexate, sulfasalazine, leflunomide, hydroxychloroquine.
Methotrexate can cause myelosuppression and liver cirrhosis, so monitor FBC and LFTs.

For flare ups use corticosteroids oral/IM

2nd line if 2 DMARDs not working: TNF inhibitors e.g. etanercept, infliximab.

Rituximab- monoclonal antibody results in B cell depletion. Infusion reactions are common.

Question 10

How to manage RA and pregnancy?

Answer 10

Defer conception until symptoms are under control.
Usually a mild improvement of symptoms during pregnancy but a flare up after delivery.

Need to stop methotrexate at least 6 months before conception.

During pregnancy sulfasalazine and hydroxychloroquine are considered safe to use.
NSAID use should be stopped 2-3 weeks before delivery.